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The development of a novel reflection cell for conventional electrodes facilitates the performance of spectroelectrochemical measurements. This device allows researchers to work in aqueous solutions as well as in organic media due to its chemical resistance.

Simultaneous determination of Sb and Bi in an alkaline ZnO solution.

Determination of Zn, Cd, Pb, and Cu in chili sauce after digestion UV.

Nickel and cobalt can be determined in drinking water in one run by adsorptive stripping voltammetry (AdSV). Dimethylglyoxime (DMG) is used as complexing agent at a pH value of 9.3.

The presence of copper in fuel ethanol blends has gained considerable attention since Cu2+ catalyzes oxidative reactions in gasoline leading to olefin decomposition and gum formation. Cu2+ in ethanol can easily be determined using anodic stripping voltammetry (ASV) in ethanol/gasoline blends without any sample pretreatment.

Lead is known to be highly toxic to humans as it interferes with enzyme reactions. Chronic lead poisoning can be caused by lead leaching into drinking water from piping systems. The current provisional guideline value in the World Health Organization’s «Guidelines for Drinking-water Quality» sets a maximum concentration of 10 μg/L. With a limit of detection (LOD) of 0.2 μg/L, anodic stripping voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS) to determine lead in drinking water. While AAS (and competing methods) can only be performed in a laboratory, anodic stripping voltammetry can be used conventionally in the laboratory or alternatively in the field with the 946 Portable VA Analyzer. The determination is carried out on a silver film applied to the scTRACE Gold electrode.

Zinc is an essential trace element for humans. Excessive intake of zinc in higher concentrations can be harmful, however. There is no guideline value for zinc in the World Health Organization’s «Guidelines for Drinking-water Quality» because typical levels usually found in drinking water are of no concern. Anodic stripping voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS) for the determination of zinc in drinking water. While AAS (and competing methods) can only be performed in a laboratory, anodic stripping voltammetric determinations can be used conventionally in the laboratory or alternatively in the field using with 946 Portable VA Analyzer. The determination is carried out on the scTRACE Gold electrode.

This poster demonstrates the feasibility of coupling a Metrohm IC system to a PerkinElmer NexION ICP-MS, operated under Empower 3 Software.Using a Metrosep Carb 2 column, the chromatographic separation of both species was achieved with a high resolution. Low background and high sensitivity allow determination in the low ng/L range.Optimal separation and full complexation of Cr(III) is already possible with EDTA concentrations from 40 μmol/L in low matrix solutions and may need to be increased depending on the sample matrix.Handling of the system was easy and user friendly. It was shown that speciation of Cr(III) and Cr(VI) can be carried out on this system utilizing a professional data system for acquisition, processing, and reporting.

The determination of the lead content in engine fuels has gained considerable importance since the introduction of the catalytic converter technique. Even small contents of lead interfere with the effectiveness of the catalysts or may destroy them. On the other hand, there are still many vehicles on the roads which run on leaded fuel (addition of tetraalkyl lead). Here also the knowledge of the lead content is of interest.With reference to DIN 51769 and ASTM 0-1269 a simplified procedure for the determination of lead in petrochemical products is described. The products are digested with HCl and the lead compounds are converted to lead(II) chloride. After extraction with water, the inverse voltammetric Pb determination is carried out.

The method described allows the determination of W(VI) traces in the range 0.2 to 50 µg/L (ppb). Traces of organic compounds present in the samples (e.g. natural waters) interfere. They have to be removed by UV digestion (e.g. 705 UV Digester). Interference by Fe(III) up to a concentration of 100 mg/L is eliminated by reduction to Fe(lI) with ascorbic acid. If the amount of Cu(II) in the sample exceeds the amount of W(VI) by a factor of 200 or more, the Cu ions have to be bound with thiourea. Moreover, the concentration of Cu(II) should not exceed 5 mg/L. The determination is made by adsorptive stripping analysis in the DP mode.

Determination of sodium, ammonium, methylamine, guanidine (Gu), and aminoguanidine (Agu) in wastewater using cation chromatography with direct conductivity detection.

Determination of magnesium, strontium, and barium in produced water using cation chromatography with direct conductivity detection.

Metrohm Inline Preconcentration Technique with matrix elimination (MiPCT-ME) is a powerful method that combines preconcentration, matrix elimination, and multilevel calibration. In this Application Note, the methodology is applied to the determination of traces of sodium in addition to 2 mg/L ammonia. The Metrosep C 6 - 250/4.0 column is used for selectivity reasons.

Within the scope of the USP monograph modernization, potassium is determined in potassium bicarbonate effervescent tablets for oral suspension applying cation chromatography with direct conductivity detection. The separation is performed on a Metrosep C 6 - 150/4.0 column (L76). All acceptance criteria are fulfilled.

Hexavalent chromium, also referred to as chromate or Cr(VI), is considered toxic and potentially carcinogenic, which is why its concentrations in drinking water should be kept as low as possible. Determination of Cr(VI) is performed by combining ion chromatography with ICP/MS. Separation takes place on the Metrosep A Supp 1 Guard/4.6.

Determination of sodium dodecylsulfate (SDS, sodium laurylsulfate) using anion chromatography with direct conductivity detection.

This Application Note shows that visible near-infrared spectroscopy (Vis-NIRS) can determine the sun protection factor (SPF) of sunscreen products. Thanks to measurement durations of less than 30 seconds, NIR spectroscopy is ideally suited for rapid and reliable quality control.

Rhodium and platinum can be determined in water samples after UV digestion and complexation by adsorptive stripping voltammetry (AdSV) at the HMDE.

Zinc, cadmium, lead, and copper can be determined in wastewater samples after UV digestion by anodic stripping voltammetry (ASV) according to DIN 38406 part 16.

This Application Note describes the polarographic determination of selenite in electroplating baths used in the production of copper indium gallium diselenide thin-film solar cells (CIGS cells). The CIGS absorber layer is electrodeposited on a molybdenum-coated substrate. Selenite analysis is carried out after dilution of the sample with sulfuric acid as supporting electrolyte.

Iron is an essential element in human nutrition. It can be present in drinking water as a result of water treatment or from corrosion in the water piping system. There is no guideline value for iron in the World Health Organization’s «Guidelines for Drinking-water Quality» because typical levels usually found in drinking water are of no concern. However, there are national limit values in various countries. The European Union has set a guideline indicator value for iron of 200 μg/L. Voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS) for the determination of iron in drinking water. While AAS (and competing methods) can only be performed in a laboratory, anodic stripping voltammetric determinations can be done used conventionally in the laboratory or alternatively in the field using the with 946 Portable VA Analyzer. The determination is carried out with adsorptive stripping voltammetry (AdSV) using 2,3-dihydroxynaphthalene (DHN) on the scTRACE Gold electrode.

Electrochemical impedance spectroscopy (EIS) is a powerful technique which provides information about the processes occurring at the electrode-electrolyte interface. The data collected with EIS are modeled with a suitable electrical equivalent circuit. The fitting procedure will change the values of the parameters until the mathematical function matches the experimental data within a certain margin of error. In this Application Note, some suggestions are given in order to get acceptable initial parameters and to perform an accurate fitting.

The poster shows the use of Vis-NIR spectroscopy for the simultaneous quantification of cobalt content, solids content, relative density and viscosity in paint driers as an outstanding alternative to conventional wet chemical laboratory methods. The advantages of the expanded wavelength range over the visible range become clear in this application: the visible range (400 – 780 nm) correlates directly with the cobalt content; the NIR range (780 – 2500 nm) is used for determining the chemical and physical parameters.

Determination of Bethanechol chloride and calcium in tablets using cation chromatography with direct conductivity detection.

Potassium citrate and citric acid oral solutions act as systemic alkalizers. Potassium assays, validated per USP <621> and <1225>, use IC with L76 cation-exchange columns.

Determination of ferrous ions in heat exchanger and vessel acid wash solutions, for measuring the effectiveness of acid inhibitors used in the solutions. Depending on the condition of the sample, the lower practical limit for the determination will vary from approximately 20-100mg/Kg Fe2+. Samples with high silicic acid contents require relatively large amounts of dilution water to render them mobile, and this limits the aliquot size and hence the amount of Fe2+ which can be analyzed.

Determination of chromium in leather waste solutions in the range between 1000 and 30,000 ppm.

This Application Note discusses the standardization of thiosulfate titrant for use in the determination of copper with thermometric titration.

A setup that allows online sampling is crucial for immediate and contamination-free analysis of power plant water samples. This application recommends a setup that facilitates simultaneous anion/cation determinations. Automated inline sample preparation combines variable preconcentration (MiPCT) and calibration with a single multi-ion standard. AN-Q-004 displays the respective cation results.

Determination of vanadium(IV) and vanadium(V) in Benfield solution using anion chromatography with UV detection.

The Benfield Process is a well known procedure to remove H2S and CO2 from petroleum and industrial gases. Vanadium pentoxide is added as a corrosion inhibitor and is most effective in a certain V(IV)/V(V) ratio. Therefore, speciation and determination of V(IV) and V(V) is important. This speciation is easily achieved on A Metrosep A Supp 5 - 50/4.0 column with EDTA as an eluent and UV/VIS detection at 282 nm.

Determination of Hg in chili sauce after UV digestion.

Platinum in urine can be determined by adsorptive stripping voltammetry (AdSV) after UV digestion of the sample.

Presence of thallium in surface water is an indicator of industrial effluents and poses a serious health hazard if imbibed. Monitoring of thallium concentration can easily be done with anodic stripping voltammetry on the silver film modified scTRACE Gold. This non-toxic method allows the determination of thallium concentrations between 10–250 µg/L and can be carried out with the 946 Portable VA Analyzer.

The provisional guideline values in the World Health Organization’s (WHO) «Guidelines for Drinking-water Quality» are set to 3 µg/L for cadmium and 10 µg/L for lead. The anodic stripping voltammetry (ASV) technique performed on the ex-situ mercury film modified Metrohm DropSens screen-printed electrode (SPE) can be used to simultaneously detect concentrations as low as 0.3 µg/L for both elements. This is suitable to monitor the WHO guideline values. The main advantage of this method lies in the innovative and cost-effective screen-printed electrode.

Iron is an essential element in the human diet and is found in many natural and treated waters. Therefore, the World Health Organization (WHO) does not issue a health-based guideline value for iron. Higher concentrations of iron in surface waters can indicate the presence of industrial effluents or outflow from other operations and sources of pollution. Because of this, precise, rapid, and accurate iron determination at low concentrations in environmental and industrial samples is of great importance. This can be achieved with the method described in this Application Bulletin.

Potassium is naturally occurring in surface water caused by weathering of stones and soil. As potassium in drinking water is regulated and should not exceed a certain threshold value, it is necessary to assess the potassium concentration.This can easily be done by direct measurement using a potassium selective electrode. First, a calibration is performed, afterwards, the samples are measured within tens of seconds. This is a fast, inexpensive and reliable method to determine the potassium content in various water samples.

This Application Note looks at the photometric determination of manganese sulfate using the Optrode (610 nm). Manganese is titrated with EDTA; Eriochrome Black T is used as indicator. The method complies with Ph. Eur. and the USP.

Cd, Pb, and Cu can be determined in one run in acetate buffer by anodic stripping voltammetry (ASV).

Mo is determined by polarography at the SMDE in nitric acid solution.

Due to the toxicity and the detrimental effects of nickel and cobalt on human health, their concentrations in drinking water must be controlled. Therefore, EU the legislation specifies 20 µg/L as the limit value for nickel in drinking water. The current provisional guideline value for Ni in the World Health Organization’s «Guidelines for Drinking-water Quality» is set to a maximum concentration of 70 µg/L. To monitor the concentrations of Ni and Co with the 884 Professional VA, a method for simultaneous determination on the glassy carbon electrode (GC-RDE) modified with a Bi film is used.

The guideline value for total chromium in the World Health Organization’s (WHO) «Guidelines for Drinking-water Quality» is 50 µg/L. Chromium(VI) is more toxic than its trivalent form (Cr(III)) and is also less abundant. Therefore a robust and sensitive method is required to monitor its concentration in drinking water. The mercury film modified scTRACE Gold can be used to monitor chromium(VI), offering easy handling and a high grade of stability.

The coupling of ion chromatography and inductively coupled plasma mass spectrometry (ICP/MS) leads to a high-performance measurement system that masters several particularly challenging analyses. It enables for example reliable determination of element compositions, oxidation states and chemical bonds. This information is used, for example, for assessing the toxicity of medications, environmental and water samples as well as foods and beverages.

In an acidic solution (containing NH4F * HF, Al(NO3)3 / KNO3) sodium forms NaK2AlF6 which precipitates in an exothermic solution, enabling analysis by thermometric titration. Several foods were analyzed, namely bouillon, gravy, tomato ketchup, corn chips, pretzel sticks as well as crackers. The reproducibility of the results was good. After weighing in and adding solutions, samples were crushed with a polytron to ensure homogeneity in the measuring solution. Relative standard deviations were between 0.08% and 3.75%. In addition to this application bulletin, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs

As an alternative to flame photometry, ion chromatography with non-suppressed conductivity detection has been approved by the USP as a validated method to quantify potassium and sodium content in potassium and sodium bicarbonates and citric acid effervescent tablets for oral solution. The present IC method has been validated according to USP General Chapter <621>.

As an alternative to flame photometry, ion chromatography with non-suppressed conductivity detection has been approved by the USP as a validated method to quantify potassium content in potassium bicarbonate and potassium chloride effervescent tablets for oral solution. The Metrosep C 6 - 150/4.0 column (L76) provides the required separation of potassium and magnesium. The present IC method has been validated according to USP General Chapter <621>.

Potassium bitartrate for pharmaceutical use must comply with USP requirements. The actual monograph (USP 42) uses a colorimetric method for the determination of ammonium impurities. Ion chromatography allows the measurement in a single determination under the same conditions used for the potassium assay (see AN-C-181). In the course of the USP monograph modernization, this ion chromatographic approach makes this type of analysis even easier.

The assay of calcium acetate, often used as a phosphate binder for dialysis patients, can be performed with ion chromatography (IC) as per USP <621> and <1225>.

Solids used in road construction were analyzed with a hand-held Raman spectrometer. The materials examined are conventional pigments and resins, e.g., CaCO3, TiO2 and DEGALAN®. The measured spectra differ considerably from one another. In order to assess the main differences between the chemical structures, the peaks of the spectra were assigned to the functional groups that generated them.

Raman spectroscopy with PLS modeling enables rapid, accurate, nondestructive quantification of the total phosphate content in solution with minimal sample preparation.

Higher levels of copper in drinking water are usually caused by corrosive action of water leaching copper from copper pipes. While copper is an essential nutrient for the human organism, ingestion of higher concentrations have an adverse effect on human health. The current World Health Organization’s «Guidelines for Drinking-water Quality» recommend a maximum concentration of 2000 μg/L. With a limit of detection (LOD) of 0.5 μg/L, anodic stripping voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS) for the determination of copper in drinking water. While AAS (and competing methods) can only be performed in a laboratory, anodic stripping voltammetry can be used conventionally in the laboratory or alternatively in the field with the 946 Portable VA Analyzer. The determination is carried out on the scTRACE Gold electrode.

It is widely accepted that prolonged exposure to hexavalent chromium compounds can have dire health effects. This has led to increased regulation of chromium-containing products and greater demand for technologies that can positively identify hexavalent chromium in potential matrices. These include paints, dyes, and primers, which can pose a problem for interrogation with Raman, as strongly colored materials often exhibit fluorescence when stimulated at 785 nm. Fluorescence can obscure the Raman signal and prevent positive identification. MIRA XTR DS provides all the functionality of handheld material ID with a new capability that selectively eXTRacts the Raman signal from fluorescent materials. Fluorescence rejection at 785 nm provides higher sensitivity and resolution than 1064 nm systems, as well as a much wider scope of applications amenable to Raman spectroscopy. MIRA XTR DS offers a comprehensive and versatile material ID test solution for field operations.

Ion measurement can be conducted in several different ways, e.g., ion chromatography (IC), inductively coupled plasma optical emission spectrometry (ICP-OES), or atom absorption spectroscopy (AAS). Each of these are well-established, widely used methods in analytical laboratories. However, the initial costs are relatively high. In contrast, ion measurement by the use of an ion-selective electrode (ISE) is a promising alternative to these costly techniques. This White Paper explains the challenges which may be encountered when applying standard addition or direct measurement, and how to overcome them in order for analysts to gain more confidence with this type of analysis.

This Application Bulletin describes methods for the polarographic and voltammetric determination of small quantities of chromium in water, effluent water and biological samples. Methods for the sample preparation for various matrices are given.

"Molybdenum is an essential trace element for plant growth. Since it occurs in natural waters only in trace amount, a very sensitive method of determination is needed. Using the following polarographic method, it is possible to determine 5·10-10 mol/L resp. 50 ng/L.The principle of the method is based on the reaction between the molybdate ion MoO42- and the complexing agent 8-hydroxy-7-iodo-quinoline-5-sulfonic acid (H2L) to form a MoO2L22- complex, which is adsorbed on the mercury electrode. The adsorbed Mo(VI) is reduced electrochemically to the Mo(V) complex. The hydrogen ions present in the solution oxidize Mo(V) again spontaneously to form the Mo(VI) complex, which is thus newly available for electrochemical reduction. This catalytic reaction is the reason for the high sensitivity of the method.Tungsten W(VI) exhibits practically the same electrochemical behavior as molybdenum, but is not described in detail in this Application Bulletin."

Excess sodium intake increases the risk of health issues. Ion-selective electrodes (ISEs) offer a fast, accurate, and cost-effective method for measuring sodium in food.

Differentiation between Cr(III) and Cr(VI) is possible following ISO 24384 guidelines by combining ion chromatography with inductively coupled plasma mass spectrometry.

The presented IC system with inline sample preparation allows the determination of traces of lithium and sodium (ppt) in the presence of ppm quantities of ammonium and ethanolamine.

This poster looks at the possibility to modify the existing EPA Method to meet California's rigorous public health goal (PHG) of 0.02 µg/L. After optimizing instrument settings and method parameters, a method detection limit (MDL) of 0.01 µg/L is obtained.

The determination of the potassium content in foodstuffs plays a major role in the food and dietary supplement industry, as potassium is an essential mineral nutrient for humans. It is an important intracellular cation and also plays a important role in processes within cells, where it is involved in the regulation of numerous body functions like blood pressure, cell growth and muscle control.As a dietary supplement, potassium is present in e.g., electrolyte powder, electrolyte drinks and food supplements. To quantify the potassium content in such products, e.g. flame photometry can be used. In this work, an alternative, ion measurement by standard addition, is described, which is fast, inexpensive and simple to use.

Groundwater contains many minerals, but can be contaminated by sodium-rich leachate from landfills. Accurate Na determination in water is possible following AOAC 976.25 using the Na-ISE.

Chromate (Cr(VI)) or hexavalent chromium is carcinogenic. Its use is restricted. Chromate has to be analyzed in a large range of products starting with drinking water, wastewater (e.g., from leather production), over toys to RoHS-regulated substances. Besides ion chromatographic determination applying conductivity detection, the method described here is suitable especially for lower concentrations.

To reduce the toxic effects of cadmium on the kidneys, skeleton, and the respiratory system, as well as the neurotoxic effects of lead, the provisional guideline values in the World Health Organization’s (WHO) «Guidelines for Drinking-water Quality» are set to a maximum concentration of 3 µg/L for cadmium and 10 µg/L for lead.The powerful anodic stripping voltammetry (ASV) technique on the ex-situ mercury film modified glassy carbon electrode is more than sufficient to monitor the proposed WHO guidelines for Cd and Pb in drinking water.

No health-based guideline value exists for zinc. However, to maintain good quality municipal drinking water, the United States Environmental Protection Agency (US-EPA) set a maximum concentration of 5 mg/L as the limit value. Typical concentrations in surface and ground waters are between 10–40 μg/L Zn, with values up to 1 mg/L in tap water. Anodic stripping voltammetry (ASV) on the ex-situ mercury film modified glassy carbon electrode provides a less complex alternative to atomic absorption spectroscopy (AAS) for zinc determination in drinking water.

Cobalt is an essential element for humans because it is a component of vitamin B12. While small overdoses of cobalt compounds are only slightly toxic to humans, larger doses from 25–30 mg per day may lead to skin, lung, and stomach diseases, as well as liver, heart, and kidney damage, and even cancerous growths. The same is valid for nickel, which can lead to inflammation at higher concentrations. Drinking a large amount of water containing nickel can cause discomfort and nausea. In the EU the legislation specifies 0.02 mg/L as the limit value for the nickel concentration in drinking water. This concentration can be reliably determined with the method described in this Application Bulletin.

The guideline value for chromium in the World Health Organization’s (WHO) «Guidelines for Drinking-water Quality» is 50 µg/L. It should be noted here that chromium concentrations are often expressed as total chromium and not as chromium(III) or (VI). Chromium(VI) is responsible for changes in genetic material, and is found in significantly lower concentrations than Cr(III). Therefore an extremely sensitive method is required to monitor Cr(VI) in drinking water.The powerful adsorptive stripping voltammetry (AdSV) technique on the ex-situ mercury film modified glassy carbon electrode using DTPA as complexing agent can be used to determine such low concentrations.

Determination of lithium, sodium, ammonium, and monoethanolamine (MEA) using cation chromatography with direct conductivity detection and Metrohm Inline Preconcentration and Inline Calibration.

2-amino-N-(2,2,2-trifluoroethyl)-acetamide is a organic building block for synthesis of pharmaceutical products. Its purity is crucial for the success of the respective synthesis step. 2,2,2-trifluoroethylamine, glycine, and inorganic cations are of interest. Their total peak area is required to be < 2 % of the peak area of all peaks above the reporting level. Separation and quantification is achieved on a Metrosep C 4 - 250/4.0 cation column.

Water of the water-steam cycle of boiling water reactors (BWR) needs to be free of corrosive anions. Analyzing these trace anions allows the parallel determination of chromate, which is a potential corrosion product. Automated sample preparation includes variable Inline Preconcentration (MiPCT) and automatic calibration with a single multi-ion calibration standard.

Manufacturers and laboratories must use validated methods to determine the zinc content in skin care products and pharmaceutical supplements to meet strict quality standards set by the United States Pharmacopeia and National Formulary (USP-NF). USP-NF has updated the zinc monograph (General Chapter <591>, Zinc Determination) and replaced the existing identification procedure of titration with ion chromatography (IC). The analysis involves separating Zn using a Metrosep A Supp 10 column followed by post-column reaction using 4-(2-pyridylazo)resorcinol and detection at 530 nm.

Determination of Cd, Pb, and Sb in acetic acid.

Boiler feed water is a working medium in thermal power plant. To keep corrosion low, the pH value should be in the slightly alkali range, which is why amines are added to the feed water. This addition must be monitored regularly. Also important is the monitoring of the sodium concentration, because an increase of this indicates that cooling water is seeping into the condenser. Ion chromatography with conductivity detection following sequential suppression is the optimum system for monitoring, particularly in combination with intelligent Sample Preconcentration and Matrix Elimination.

Determination of sodium, potassium, and silica values in sodium and potassium silicates.

Determination of fluoride, sulfate, iodide, and molybdate in mineral tablets using anion chromatography with conductivity detection after chemical suppression.

This Application Note describes the photometric determination of zinc sulfate using the Optrode at a wavelength of 610 nm. Complexometric titration of zinc requires EDTA as titrant and Eriochrome Black T as indicator. The method fully complies with Ph. Eur. and USP.

This Application Bulletin describes the determination of titanium by adsorptive stripping voltammetry (AdSV) using mandelic acid as complexing agent. The method is suitable for the analysis of ground, drinking, sea, surface and cooling waters, in which the concentration of titanium is of importance. The methods can, of course, also be used for the trace analysis in other matrices.The limit of detection is approx. 0.5 µg/L.

In natural gas production, the removal of contaminants, and in particular acidic gases such as H2S and CO2, is exceptionally important. These acidic gases are removed in the amine wash through chemical treatment with amines or alkanol amines. This application shows a convenient and precise analysis with the separation of various amines and standard cations on a column of the Metrosep C 6 - 250/4.0 type with subsequent direct conductivity detection.

Water hardness is often determined photometrically using two different indicators and while performing the determination at two different pH values. Additionally, the determination itself is subjective, as the color change is determined by the analyst and not by an analytical device.This application note introduces a more robust option to easily assess calcium, magnesium, and total hardness in water by using the Cu-ISE and two different titrants. Sample preparation is identical for both analyses and can therefore be automated without any issues.

The content of organic matter, limestone, silt, clay, and sand, along with pH value and exchangeable calcium and magnesium in soil can be determined in seconds with NIRS.

Determination of fluoride, formate, acetate, chloride, nitrite, bromide, nitrate, sulfate, oxalate, and molybdate using anion chromatography with conductivity detection after chemical suppression and Metrohm Inline Dialysis.

Iron can be determined in ethanol by adsorptive stripping voltammetry (AdSV) at the HMDE. PIPES buffer is used as supporting electrolyte and catechol as complexing agent at a pH value of 7.0.

This Application Bulletin describes the determination of inorganic mercury in water samples by anodic stripping voltammetry using the scTRACE Gold sensor. With a deposition time of 90 s, calibration is linear up to a concentration of 30 µg/L; the limit of detection lies at 0.5 µg/L.

The ASTM D8192 standard allows analysts to determine water hardness in different water matrices by complexometry with automated photometric endpoint recognition, increasing the reproducibility and the precision of the results.

Chromate is allergenic, carcinogenic and extremely toxic. It is therefore subject to strict monitoring. It is present in different concentrations in drinking water, toys, textiles, leather and many other materials. Metrohm has developed various methods for ion chromatographic determination of chromium(VI) which, thanks to Inline Sample Preparation, are suitable for a variety of matrices and concentration ranges – from ng/L to mg/L.

OMNIS Client/Server boosts business performance with scalable server management, cutting costs by reducing hardware, energy use, and maintenance across locations.

This Application Bulletin describes …

ASTM D8192 describes the photometric titration of the total hardness, calcium hardness, and magnesium hardness in water with an optical sensor for objective endpoint indication, increasing precision and reliability. The method is suitable for both colored and colorless samples such as groundwater, surface water, wastewater, and drinking water. Using a fully automated OMNIS system equipped with an Optrode ensures that the sample preparation and analysis are repeatable.

Zn and Pb are determined by anodic stripping voltammetry (ASV) in acetate buffer at pH 4.6.

Qualitative determination of chloride, phosphate, and sulfate as well as chlorite, nitrite, chlorate, bromide, and chromate in urine using anion chromatography with conductivity detection after chemical suppression.

Handheld Raman is ever evolving. The combination of large libraries, a compact and easy-to-use system, and predictive Hazmat software make MIRA DS a powerful tool for defense and security professionals. Identify on-site materials, get hazard information, and make quick decisions about response to dangerous situations.

Free white paper gives comprehensive overview of how to reliably assess the quality of infant formula with ion chromatography.

Hexavalent chromium (chromate) is known to be carcinogenic if inhaled, and suspected to be carcinogenic if ingested. EPA Method 218.7 allows to determine chromate in drinking water down to the sub-µg/L range (method detection limit, MDL = 15 ng/L). Post-column reaction with 1,5-diphenylcarbazide and subsequent visible detection at 530 nm is applied.

Metrohm Raman presents a unique handheld materials identification system designed to meet the needs of defense and security professionals. Meet Mira DS, the most adaptable Raman analyzer available today. Mira DS was developed directly in response to requests from first responders in the field for a small, rugged, automated materialsidentification system that ensures the safety of the user in any situation.

This Bulletin describes analysis methods for determining the following parameters: pH value, total titratable acid, ash alkalinity, formol number, total sulfurous acid, chloride, sulfate, calcium, and magnesium. These methods are suitable for the analysis of jams, fruit and vegetable juices, and their concentrates.

Cadmium, lead, and copper can be determined simultaneously in oxalate buffer by anodic stripping voltammetry (ASV) after digestion with sulfuric acid and hydrogen peroxide. Tin present in the sample does not interfere with the determination of lead.For the voltammetric determination of tin please refer to Application Bulletin no. 176.

Determination of fluoride, formate, chloride, nitrite, bromide, nitrate, sulfate, oxalate, and molybdate in a coolant using anion chromatography with conductivity detection after chemical suppression and Metrohm Inline Dialysis.

Efficiently analyze food products with ion chromatography (IC). Discover its robust applications in quality control for beverages, food additives, and dairy.

Determination of acetate, chloride, nitrite, bromide, nitrate, phosphate, sulfate, oxalate, fumarate, and molybdate using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, hypophosphite, chlorite, bromate, chloride, nitrite, bromide, chlorate, nitrate, phosphite, phosphate, sulfate, arsenate, iodide, chromate, and perchlorate using anion chromatography with conductivity detection after gradient elution and chemical suppression.

Hexavalent chromium (Cr(VI)) is regarded as being toxic and potentially carcinogenic. Its concentration in drinking water should therefore be kept as low as possible. The determination of Cr(VI) is performed using ion chromatography. The separation takes place on the Metrosep A Supp 10 - 250/2.0 separation column. The presence of Cr(VI) is determined photometrically following post-column reaction (PCR) with diphenylcarbazide.

An analytic chemist in your back pocket. A forensic laboratory in a suitcase. A HazMat team in the trunk of your car. First responders need all the help they can get when faced with potentially dangerous substances. Mira DS from Metrohm Raman is a sophisticated chemical analyzer that replaces the specialist with automation. The push of a button initiates proprietary Smart Acquire routines to optimize acquisition parameters and collect the highest quality spectra. These spectra are automatically subjected to library search and Mixture Matching routines capable of identifying up to three components of a mixture. When hazardous substances are detected, the user is alerted to immediate action with color-coded warnings.

Determination of boric acid in electroless plating solutions.

Potassium is one of the most common elements and can be found in many different minerals and other potassium compounds. It is of importance for humans, animals and plants as it is an essential mineral nutrient and involved in many cellular functions like cell metabolism and cell growth. For these reasons, it is important to be able to declare the potassium content of food or soil to reduce problems that may arise by a potassium deficiency or extensive consumption.This bulletin describes an alternative to flame photometric method using an ion selective electrode and direct measurement or standard addition technique. Several potassium determinations in different matrices using the combined potassium ion-selective electrode (ISE) are presented here. Additionally, general hints, tips and tricks for best measurement practice are given.

This White Paper explores the critical role of advanced online and inline process analysis in brine chlorine operations, emphasizing their advantages over traditional methods.

Thermometric titration is used for the determination of hydrochloric acid and nitric acid in acid baths. The entire acid content is titrated with caustic soda in the initial titration; the hydrochloric acid content is then determined in a second titration using silver nitrate solution.

UV/VIS detection is one of the most sensitive detection techniques in trace-level chromatography. Sometimes, however, spectrophotometric detection lacks sensitivity, selectivity or reproducibility and chemical derivatizations are required. By using Metrohm`s rugged and versatile flow-through reactor, single- or multi-step derivatizations can be done fully automatically, in either pre- or post-column mode at any temperature between 25…120 °C. The variable reactor geometry allows to adjust the reactor residence time of the reactants according to derivatization kinetics. The flexibility of the reactor is demonstrated by optimizing four widespread post-column techniques: the relatively slow ninhydrin reaction with amino acids and the fast derivatizations of silicate, bromate and chromate(VI).

This bulletin describes the determination of calcium, magnesium, and alkalinity in water by complexometric titration with EDTA as titrant. It is grouped into two parts, the potentiometric determination and the photometric determination.There are multiple definitions of the different types of water hardness. In this Application Bulletin, the following definitions are used: alkalinity, calcium hardness, magnesium hardness, total hardness, and permanent hardness. Explanations of these definitions and other expressions are provided in the Appendix.Determination of alkalinity during the photometric part is carried out in a separate acid-base titration before the complexometric titration of calcium and magnesium in water. Permanent hardness can be calculated from these values. The determination of calcium and magnesium in beverages (fruit and vegetable juices, wine) is also described.The photometric part includes the determinations of total and calcium hardness and thereby indirectly magnesium hardness using Eriochrome Black T and calconcarboxylic acid as indicators (in accordance with DIN 38406-3).

This application explains ohmic iR drop in electrochemical cells, its causes, and strategies to minimize its impact for accurate and reliable potential measurements.

Nitric acid, phosphoric acid, and acetic acid are easily determined in etching baths using thermometric titration (TET). Compared to potentiometric titration, TET is faster and more convenient. Analysis is complete in less than two minutes.

Thermometric titration can be used for the ready determination of sulfuric acid and phosphoric acid in acid mixtures. An endpoint for each acid appears on the titration curve that can be used to quantify the respective acid.

Thermometric titration is used for the determination of hydrochloric acid and phosphoric acid in acid mixtures. Two endpoints appear on the titration curve that are used for the determination of the two acids.

Determination of anionic surfactants in a nickel plating bath by potentiometric titration with TEGO®trant A100 using the «Ionic Surfactant» electrode.

This Application Bulletin describes the determination of mercury by anodic stripping voltammetry (ASV) at the rotating gold electrode. With a deposition time of 90 s, the calibration curve is linear from 0.4 to 15 μg/L; the limit of quantification is 0.4 μg/L.The method has primarily been drawn up for investigating water samples. After appropriate digestion, the determination of mercury is possible even in samples with a high load of organic substances (wastewater, food and semi-luxuries, biological fluids, pharmaceuticals).

Determination of mixtures of phosphoric, nitric, and acetic acids used in etching aluminum in the manufacture of semiconductor devices.

Thermometric titration is used to determine hydrofluoric acid and nitric acid in etching baths containing ethanol and acetonitrile. Two endpoints appear on the titration curve that are used individually for the quantification of the respective acid.

Determination of nitrate and sulfate in sodium phosphinate (sodium hypophosphite) using anion chromatography with conductivity detection after chemical suppression.

Determination of nitrate in a nickel plating bath using anion chromatography with UV/VIS detection (205 nm) after chemical suppression.

Special brighteners are used in electroplating baths in order to provide the refined surfaces with greater brightness. The concentration of brighteners must be kept constant at all times in order to ensure uniform end product quality. This Application Note describes how brighteners are determined in parallel with IC and CVS. The corresponding CVS application can be found under AN-V-183.

Acid copper baths are mainly used for the copper deposition on semiconductor wafers. Small amounts of chloride increase the speed of deposition and reduce anode polarization. However, higher concentrations are undesired, as this will decrease the quality of the copper deposition. Therefore, it is quite important to monitor the amount of chloride to have an effective, yet high-quality copper deposition process.In this Application Note, a fully automated solution based on titration is presented. In comparison to ion chromatography, titration offers the benefit that no dilution of the sample is necessary, and the hardware is comparatively low-priced. Furthermore, the fully automated solution allows users to minimize handling errors, to reduce workloads, and to guarantee outstanding reproducibility.

The rapid growth of the Earth's population has led to massive increases in the consumption of energy and resources and in the production of consumer products and chemicals. It is estimated that 17 million chemical compounds are currently on the market, of which 100,000 are produced on a large industrial scale. Many of these enter the environment. This leads to a demand for sensitive analytical procedures and high-performance analytical instruments.pH value, conductivity and oxygen requirement are important characteristics in water and soil analysis. The first two of these can be determined rapidly; for the third, the titration that is used is also the one used in numerous single determinations. This article describes several important standard-compliant determinations in water and soil analysis.

Thermometric titration is used to determine hydrochloric acid and hydrofluoric acid (hydrogen fluoride) in etching baths containing ethanol and acetonitrile. Two endpoints appear on the titration curve that are used individually for the quantification of the respective acid.

Determination of citrate and saccharin in a nickel plating bath using ion-exclusion chromatography with direct conductivity detection.

The determination of suppressor with dilution titration (DT) involves numerous additions with standard solution or sample to reach the evaluation ratio. Usually fixed, equidistant addition volumes are used. With smartDT, variable addition volumes are used that are automatically calculated by the software. At the beginning, the volumes are bigger. Towards the evaluation ratio, the addition volume becomes smaller to guarantee a good accuracy of the result. The operator defines the first and the smallest addition volume to be used. All volumes in between are calculated by the software considering the progress of the determination. Using smartDT with intelligent addition volumes, the determination of suppressor can be significantly accelerated with the same or even better accuracy than with the classic DT. The time saving per determination is between 20 and 40%.

This document explains how to measure Na ion concentration in diverse matrices with a sodium ion-selective electrode (Na-ISE) using direct measurement and standard addition.

This Bulletin describes potentiometric titration methods for the determination of the acidity in milk and yoghurt according to DIN 10316, ISO/TS 11869, IDF/RM 150, ISO 6091 and IDF 86, the chloride content in milk, butter and cheese according to EN ISO 5943, IDF 88, ISO 15648, IDF 179, ISO 21422, and IDF 242. Additionally the determination of the sodium content in milk using the thermometric titration is described. The determination of the oxidation stability of butter in accordance to AOCS Cd 12b-92, ISO 6886 and GB/T 21121 as well as the determination of lactose in lactose free milk by ion chromatography is also described.For the determination of the pH value in dairy products see Application Bulletin AB-086 and for the determination of calcium and magnesium see Application Bulletin AB-235.

Determination of nitrate in a copper plating bath after conversion of nitrate to ammonium. Direct potentiometric measurement using the NH3-ISE.

Determination of nitrate in a nickel plating bath using anion chromatography with UV/VIS detection (205 nm).

The concentration of Sb(total) in an acid Cu bath is determined by anodic stripping voltammetry using hydrochloric acid as electrolyte. Due to the excess of Cu the deposition potential has to be chosen only 50 mV more negative than the Sb signal

Electroless Ni plating offers superior surface finish and corrosion resistance. Anodic stripping voltammetry allows Bi stabilizer to be monitored in Ni plating baths.

brightRC enables reliable CVS (or CPVS) brightener quantification without repeated standard additions, especially for additive systems with nonlinear signal behavior. By using external response curve (RC) calibration and flexible regression, it avoids systematic errors inherent to linear standard addition methods and significantly reduces analysis time. This makes brightRC ideal for high throughput routine control in stable copper plating baths.

This article describes the coupling of ion chromatography with mass spectrometry (IC-MS) and plasma mass spectrometry (IC-ICP/MS) for the trace analysis of potentially hazardous compounds in the environment.

Determination of borate and chloride with direct conductivity detection (exhausted MSM). After the introduction of the fresh MSM unit and after the eluent change, sulfate is analyzed with conductivity detection after chemical suppression.

Determination of suppressor «Copper GleamTM 2001 Carrier» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of brightener «Copper GleamTM 2001 Additive» in acid copper baths by modified linear approximation technique (MLAT) using cyclic voltammetric stripping (CVS).

Determination of suppressor «Cupracid BL-CT» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of brightener «Cupracid BL» in acid copper baths by linear approximation technique (LAT) using cyclicvoltammetric stripping (CVS).

Determination of suppressor «Cupraspeed» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of brightener «Cupraspeed» in acid copper baths by modified linear approximation technique (MLAT)using cyclic voltammetric stripping (CVS).

Determination of suppressor «MACuSpecTM PPR 100 Wetter» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of brightener «MACuSpecTM PPR 100 Brightener» in acid copper baths by modified linear approximation technique (MLAT) using cyclic voltammetric stripping (CVS).

Determination of suppressor «MultiBondTM 100 Part A20» in an acid copper bath by dilution titration (DT) using cyclicvoltammetric stripping (CVS).

Determination of suppressor «InPulse H6» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of brightener «InPulse H6» in acid copper baths by modified linear approximation technique (MLAT) using cyclic pulse voltammetric stripping (CPVS).

Determination of suppressor «Thru-Cup EVF-B» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of brightener «Thru-Cup EVF-1A» in acid copper baths by modified linear approximation technique (MLAT) using cyclic voltammetric stripping (CVS).

Determination of leveler «Thru-Cup EVF-R» in acid copper baths by response curve technique (RC) using cyclic voltammetric stripping (CVS).

Determination of suppressor «Top Lucina α-M» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of brightener «Top Lucina α-2» in acid copper baths by modified linear approximation technique (MLAT) using cyclic voltammetric stripping (CVS).

Determination of leveler «Top Lucina α-3» in acid copper baths by response curve technique (RC) using cyclic voltammetric stripping (CVS).

For the past three decades, Cyclic Voltammetric Stripping (CVS) has been the standard practice for analyzing organic additives in electroplating copper baths in the circuit board and wafer plating industries. The variations in the compositions of such baths have created a need for more optimized method development routines. New advancements in the hardware and software protocols for CVS have simplified the overall process of method optimization to a great extent. In this study, the process of method optimization is discussed in conjunction with these protocols.

Tartaric Sulfuric Anodizing (TSA) is an established technique for corrosion protection in the aerospace industry. It is an alternative to the environmentally harmful chromic anodizing process. As such, a method to monitor the levels of sulfuric acid and tartaric acid in TSA plating baths is required. Potentiometric titration methods have been developed, and are widely used across the industry. Their disadvantage is that two titrations with different electrodes and solvents are required.In this Application Note, an alternative method is presented, where the concentration of both acids is determined in sequence using a thermometric sensor. Compared to potentiometric titration, thermometric titration is faster and more convenient (no sensor maintenance required). On a fully automated system, the determination of both parameters takes about 7 minutes.

Monitoring organic additives in copper plating baths is crucial. The 2060 CVS Process Analyzer optimizes copper electroplating by providing precise bath control.

Determination of saccharin, benzamide, and o-toluenesulfonamide in a nickel electroplating bath using RP chromatography with UV detection.

Electroless nickel plating is an important and well established process in the surface finishing industry. In the past, the addition of small amounts of lead has widely been used to stabilize the plating bath. With the increasing number of restrictions in recent years on the use of lead in consumber products, particularly electronics, alternative stabilizers were developed and introduced. One of the stabilizers used as lead replacement is iodate. It can be used as a single additive or in combination with bismuth or antimony. This method allows the determination of iodate directly in the plating bath sample by polarography. The method is simple and fast, however, sensitive and robust.

Determination of fluoride, nitrate, phosphate, and sulfate in an etching reagent using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, nitrite, nitrate, phosphate, and sulfate in a strongly alkaline solution using anion chromatography with conductivity detection after chemical suppression.

The determination of iodate and iodide in used electroplating baths is a demanding task due to the high concentration of other ions. Iodate is used as a stabilizer for the bath and needs to be checked for proper electroplating. The use of a sodium chloride eluent, the Metrosep A Supp 5 - 250/4.0 column and direct UV/VIS detection permits the analysis of these samples without matrix interferences.

Thiourea is determined by cathodic stripping voltammetry (CSV) at the HMDE in ammonia buffer at pH 8.9. Chloride in the sample does not interfere with this determination.

Monitoring Sb(III) stabilizer levels during electroless Ni plating is critical for high-quality coatings. Anodic stripping voltammetry offers fast, reliable Sb(III) analysis.

This Application Note evaluates corrosion in Type 430 stainless steel according to ASTM G5 with VIONIC powered by INTELLO and an ASTM-compliant corrosion cell setup.

In this White Paper, details of the electronic (PGSTAT) and electrochemical cell grounding are presented together with the necessity of using a floating PGSTAT for different application and experimental examples. Due to the wide variation of experimental requirements and kinds of electrochemical cells, the use of an electrochemical instrument with a selectable floating feature (such as VIONIC) which brings additional versatility to the user is recommended.

Determination of hypophosphite, phosphite, and phosphate in a nickel bath using anion chromatography with conductivity detection after chemical suppression and inline cation exchange.

This Application Note compares the OMNIS Titrator and 888 Titrando for determinations of nitric acid, phosphoric acid, and acetic acid in an aluminum etching bath, as well as the determination of tetramethylammonium hydroxide (TMAH). Identical analysis parameters were used, showing that OMNIS delivers results on par or even better than with other established titration systems.

The concentration of Sb(III) and Sb(total) in an electroless nickel bath is determined by anodic stripping voltammetry (ASV). In c(HCl) = 0.6 mol/L only Sb(III) shows a signal. In w(HCl) = 10% the Sb(total) content is determined.

Determination of fluoride, nitrate, phosphate, sulfite, and sulfate in an etching bath using anion chromatography with conductivity detection after chemical suppression.

Determination of silicate and hexafluorosilicate (calculated) using anion chromatography with conductivity detection after chemical suppression (see AN S-277) and subsequent UV/VIS detection with post-column reaction. Hexafluorosilicate is hydrolyzed into fluoride and silicate. Both anion concentrations may be used for the calculation of the SiF62- concentration.

Electroless nickel plating is an important and well established process in the surface finishing industry. In the past the addition of small amounts of lead has widely been used to stabilize the plating bath. With the increasing number of restrictions in recent years on the use of lead in consumber products, particularly electronics, alternative stabilizers were developed and introduced. Two of the stabilizers used as lead replacement are antimony and bismuth. They can be used as a single additive or in combination with each other or iodate. This method allows the determination of antimony and bismuth directly in the plating bath sample by anodic stripping voltammetry (ASV). The method is simple and fast, however sensitive and robust

Boric acid is used in many primary circuits of nuclear power plants, in nickel plating baths, and in the production of optical glasses. Furthermore, boron compounds are found in washing powders and fertilizers. This bulletin describes the potentiometric and thermometric determination of boric acid. The determination also covers further boron compounds, when acidic digestion is applied.

This Bulletin describes three potentiometric, one photometric, one thermometric and one conductometric titration method for sulfate determination. The question of which indication method is the most suitable depends primarily on the sample matrix.Method 1: Precipitation as barium sulfate and back titration of the Ba2+ surplus with EGTA. Use of the ion-selective calcium electrode as indicator electrode.Method 2: As with Method 1, although with the electrode combination tungsten/platinum.Method 3: Precipitation titration in semi-aqueous solution with lead nitrate in accordance with the European Pharmacopoeia using the ion-selective lead electrode as indicator electrode.Method 4: Photometric titration with lead nitrate, dithizone indicator and the Optrode 610 nm, particularly suitable for low concentrations (up to 5 mg SO42- in the sample solution).Method 5: Thermometric precipitation titration with Ba2+ in aqueous solution, particularly suitable for fertilizers.Method 6: Conductometric titration with barium acetate in accordance with DIN 53127

A reference electrode has a stable and well-defined electrochemical potential (at constant temperature), against which the applied or measured potentials in an electrochemical cell are referred. A good reference electrode is therefore stable and non-polarizable. In other words, the potential of such an electrode will remain stable in the used environment and also upon the passage of a small current. This application note lists the most used reference electrodes, together with their range of use.

In the application note AN-EIS-004 on equivalent circuit models, an overview of the different circuit elements that are used to build an equivalent circuit model was given. After identifying a suitable model for the system under investigation, the next step in the data analysis is estimation of the model parameters. This is done by the non-linear regression of the model to the data. Most impedance systems come with a data-fitting program. In this application note, the way NOVA is uses to fit the data is shown.

As the determination of the exact content of individual glycerides in fats and oils is difficult and time-consuming, several fat sum parameters or fat indices are used for the characterization and quality control of fats and oils. Fats and oils are not only essential for cooking, they are also an important ingredient in pharmaceuticals and personal care products, such as ointments and creams. Consequently, several norms and standards describe the determination of the most important quality control parameters. This Application Bulletin describes eight important analytical methods for the following fat parameters in edible oils and fats:Determination of water content in accordance with the Karl Fischer method; Oxidation stability in accordance with the Rancimat method; Iodine value; Peroxide value; Saponification value; Acid value, free fatty acids (FFA); Hydroxyl number; Traces of nickel using polarography; Special care is taken to avoid chlorinated solvents in these methods. Also, as many of the mentioned methods as possible are automated.

It has been known for years that consuming too much nitrates from foodstuffs can result in cyanosis, particularly for small children and susceptible adults. According to the WHO standard, the hazard level lies at a mass concentration c(NO3-) ≥ 50 mg/L. However, more recent studies have shown that when nitrate concentrations in the human body are too high, they can (via nitrite) result in the formation of carcinogenic and even more hazardous nitrosamines.Known photometric methods for the determination of the nitrate anion are time-consuming and prone to a wide range of interferences. With nitrate analysis continually increasing in importance, the demand for a selective, rapid, and relatively accurate method has also increased. Such a method is described in this Application Bulletin. The Appendix contains a cselection of application examples where nitrate concentrations have been determined in water samples, soil extracts, fertilizers, vegetables, and beverages.

In this application note, the advantage of recording the raw time domain data for each individual frequency during an electrochemical impedance measurement is described.

The Autolab Electrochemical Quartz Crystal Microbalance (EQCM) is an optional module for the Autolab PGSTAT which can be used to control a 6 MHz crystal oscillator. This technique can be used to perform electrogravimetric measurements with detection limits in the sub μg range.

Organic halides must be monitored in the environment. Combustion ion chromatography (CIC) is used for accurate halogen analysis in solids following EN 17813:2023.

Portable Raman is used to quantify trigonelline, an alkaloid that contributes to the health benefits of some foods. A simple method to quantify the presence of diluted trigonelline in solutions using surface enhanced Raman spectroscopy is described. Portable Raman is a tool that could be used in quality control of food items such as coffee and quinoa.

Fentanyl, a powerful synthetic opioid, is illegally distributed worldwide. Overdosing can be fatal, causing symptoms like stupor, pupil changes, cyanosis, and respiratory failure. Just 2 mg of fentanyl can be lethal, depending on factors like body size and past usage. Given its severe impact, identifying and detecting fentanyl is crucial, as it has become a major public health crisis. Combining electrochemical surface-enhanced Raman spectroscopy (EC-SERS) with screen-printed electrodes (SPEs) offers a fast, effective, and precise method for detecting fentanyl.

For SERS developers and end users of SERS for specific applications to investigate low concetation levels of compounds, the centerpiece of their technological platform must be a Raman setup that provides reliable lab grade performance and is affordable and portable, allowing them to tackle real world problems. The portable i-Raman Plus system coupled with a BAC151 video microscope sampling accessory provides an ideal setup. With the performance and flexibility of use with different laser spot size and power for SERS research.

This Application Note presents a potentiometric titration method for trace H2S analysis in water on an OMNIS system using silver nitrate and an Ag Titrode.

Spectroelectrochemistry is a multi-response technique that provides electrochemical and spectroscopic information about a chemical system in a single experiment, i.e., it offers information from two different points of view. Raman spectroelectrochemistry could be considered as one of the best techniques for both the characterization and behavioral understanding of carbon nanotube films, as it has traditionally been used to obtain information about their oxidation-reduction processes as well as the vibrational structure. This application note describes how the SPELEC RAMAN is used to characterize single-walled carbon nanotubes by studying their electrochemical doping in aqueous solution as well as to evaluate their defect density.

Many electrochemical methods have been developed but are traditionally limited to aqueous media. Raman spectroelectrochemistry in organic solutions is an interesting alternative, but developing new EC-SERS procedures is still required. This Application Note demonstrates that the electrochemical activation of gold and silver electrodes enables the detection of dyes and pesticides in organic media.

The USP and FDA started to modernize several monographs and General Chapters. In many cases, IC-focused methods have replaced older, wet chemistry procedures. Learn more about the USP modernization initiative and the advantages of ion chromatography in this white paper.

Rapid inline monitoring of the major SC1/SC2 bath constituents is possible with reagent-free near-infrared spectroscopy, e.g., the 2060 The NIR-R Analyzer.

Forensic institutes examine terrorist attacks and warfare agents via trace detection analysis of the used explosives and their residuals. Of particular importance is the acquisition of «chemical fingerprints» for criminal investigation departments and governmental security agencies. Institutes for public health and environmental protection analyze such compounds that can contaminate the underlying soil and infiltrate ground water.Forensic investigation with ion chromatography (IC) using suppressed conductivity detection allows a sensitive and robust determination of anionic contaminants such as chlorate, thiosulfate, thiocyanate, and perchlorate next to the common inorganic anions over a broad concentration range.

Neutralizing amines are added to adjust pH levels within the water-steam circuit of power plants to avoid corrosion-inducing conditions. This preventive maintenance can reduce costly and critical downtimes due to corrosion, however frequent monitoring of the amine chemistry is necessary to ensure conditions stay optimal. The 2060 IC Process Analyzer featuring the Metrohm intelligent Partial Loop Technique (MiPT) option is ideal for this application, with the ability to measure trace amounts of the analytes precisely and reliably through an automated method. The benefit of using IC is that multiple analytes can be monitored simultaneously, and here the ability to measure the presence of sodium next to the high ammonium or amine concentrations could indicate that cooling water is seeping into the circuit, indicating a problem upstream.

The OMNIS Titrator equipped with a Pt Titrode accurately and reliably determines titer concentration even in diluted titrants as shown in this Application Note.

This Application Note describes carbonate determination with ion chromatography in a 50% sodium hydroxide solution. Sodium hydroxide solutions form carbonates through the absorption of carbon dioxide from ambient air. The carbonate content of an NaOH solution is determined using ion-exclusion chromatography with subsequent conductivity detection following inverse suppression. The samples are diluted 1:20 prior to the analysis and – in order to prevent CO2 absorption – stored in closed sample vessels.

This Process Application Note deals with online measurements of ammonia, nitrite, and nitrate in wastewater treatment plants. These nitrogen compounds are analyzed simultaneously using a drift-free colorimetric measurement in a multi-parameter process analyzer from Metrohm Process Analytics.

Excessive silica concentrations in the boiler feed water can lead to deposits on turbine blades and must therefore be avoided. Silica analysis is carried out via differential photometry using a leading-edge technology thermostatic cuvette module for non-sample contact at the detector. Typical concentration ranges for silica are 0–50 ppb and 0–1 ppm or higher.

Etching is a vital process in semiconductor fabrication, involving the chemical removal of layers from the wafer substrate. Strict quality control measures are necessary to determine acid etchant concentrations in mixed acid solutions (e.g., SPM, DSP, or DSP+), critical for optimizing etch rate, selectivity, and uniformity during multiple wafer etching steps. This application presents a method to measure sulfuric acid and hydrogen peroxide in etching baths simultaneously using Raman spectroscopy with the PTRam Analyzer from Metrohm Process Analytics.

EC-SERS enhances Raman sensitivity using electrochemically activated gold SPEs, enabling rapid, simplified pesticide detection without complex prep or instrumentation.

Hydrochloric acid is a strong, inorganic mineral acid with great significance in the chemical industry. The potentiometric titration of hydrochloric acid with sodium hydroxide is one of the most important and also most frequent analyses performed in the laboratory. In this Application Note, an acid-base titration is presented where the concentration of HCl is determined with NaOH using a pH electrode with an integrated Pt1000 temperature senor for the most accurate results

PEDOT:PSS is a tunable, conductive coating whose properties depend on parameters such as counter-ion selection, secondary doping, and polymerization conditions. This Application Note demonstrates the combined use of EQCM-D, Raman spectroscopy, and electrochemical methods to monitor film growth, correlating frequency and dissipation changes across harmonics with in situ spectroscopic and electrochemical signals. The introduced probe-based EQCM-D platform enables simultaneous Raman acquisition, providing a powerful tool to design and optimize PEDOT:PSS coatings.

This Application Bulletin shows the determination of the total base number in petroleum products by applying different titration types according to various standards.

This application presents the fully automated determination of acidity in jet fuel as per ASTM D3242 via photometric titration with an automatic titrator and the Optrode.

This Application Note highlights near-infrared spectroscopy as a faster, cost-effective alternative to KF titration for predicting water content in diesel fuel.

The chemicals used in the manufacture of semiconductors must exhibit an exceptional purity, because even traces of contaminants have a negative effect on electrical properties. For the manufacture of printed circuit boards, the light-sensitive photoresist applied to the substrate (wafer) is exposed to light at defined areas with the aid of a photo template and then developed in a chemical reaction. The developer contains 2.38 to 2.62% tetramethylammonium hydroxide (TMAH) and ensures that the exposed areas can be readily separated from the substrate. The monitoring of the TMAH concentration in the developer solution takes place with a process analyzer from Metrohm Applikon that is configured specially for titration. In addition to this, the analyzer helps with the mixing of the TMAH solutions.

Tris(hydroxymethyl)aminomethane (TRIS) is often used in life science applications and its purity must be monitored. This analysis is possible with ion chromatography.

Raman spectroscopy is used for material characterization by analyzing molecular or crystal symmetrical vibrations and rotations that are excited by a laser, and exhibit vibrations specific to the molecular bonds and crystal arrangements in the molecules. Raman technology is a valuable tool in distinguishing different polymorphs. Examples of portable Raman spectroscopy for identification of polymorphs and in monitoring the polymorphic transiton of citric acid and its hydrated form are presented.