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The spectrometric techniques of inductively coupled plasma–optical emission spectrometry (ICP-OES) and inductively coupled plasma–mass spectrometry (ICP-MS) are compared for their applicability to regulatory water analyses, bearing in mind recent method approval changes. ICP-OES is found to be at its limit for confident detection of several elements for drinking water analysis, but is still suitable for many environmental water quality measurements. ICP-MS is the closest there is to a universally applicable technique for water analysis.

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This tutorial illustrates the most important definitions used in high-resolution mass spectrometry and clarifies the misconceptions surrounding some of the relevant terms used in this field.

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State-of-the-art mass spectrometry (MS) techniques of growing importance to life sciences research now include not just liquid chromatography (LC)–MSn (n = 2–11), but also LC–matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF), LC-MALDI-TOF-TOF, electrospray ionization (ESI)-TOF, and LC-Fourier transform (FT) MS.

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State-of-the-art mass spectrometry (MS) techniques of growing importance to life sciences research now include not just liquid chromatography (LC)–MSn (n = 2–11), but also LC–matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF), LC-MALDI-TOF-TOF, electrospray ionization (ESI)-TOF, and LC-Fourier transform (FT) MS.

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Mass spectrometry (MS) has advanced to analyze ever-larger biomolecules with the invention of soft ionization techniques like electrospray ionization (ESI). Although ESI has provided a method of generating ions of high mass, mass spectrometers generally suffer both lower sensitivity and lower resolution as the mass-to-charge ratio of an ion increases. To extend the mass range of ionized macromolecules beyond the limits of MS, macroion mobility spectrometry utilizes ion mobility sizing to characterize charge-reduced ESI-generated macroions from >5 kDa to beyond megadalton masses. One prominent application of macroion mobility spectrometry, highlighted here, is the high sensitivity analysis of intact proteins, antibodies, and conjugates in which molecular masses range from antibody light-chain fragments to high mass immunoglobulin multimers.

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The authors discuss progress in near-field IR microspectroscopy using a photothermal probe and show how it can be applied to the spectroscopic characterization of real-world samples.

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Discover how geoscientists use Ocean Optics optical oxygen sensors for reaction kinetics studies of pyrite oxidation, which is often linked to environmental issues such as remediation monitoring in aquifers.

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Method setup and optimization steps are explored to illustrate how an ICP-MS/MS method can be defined and tested to ensure consistent performance. Users can benefit from improved interference removal performance without the complex method development inherent in the use of ion-molecule reaction chemistry

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Drug discovery scientists are continually striving to improve productivity and efficiency in their workflows. From early discovery to clinical development, existing workflow bottlenecks represent an opportunity to develop solutions to speed the process and improve productivity. The key requirements for quantitative analysis are precision, accuracy, and linear dynamic range. With any quantitative instrument, the hope is that it will be applicable to a vast range of coumpounds, ruggest, and fast. New mass spectrometry (MS) technologies are being developed that meet these criteria and permit high throughput while enabling its application to areas in which speed limitations previously curtailed its practicality. In particular, in the area of ADME profiling, new MS platforms are becoming available that increase the throughput by at least 25-fold, by combining the speed of matrix-assisted laser desorption ionization (MALDI) with the specificity of triple-quadrupole MS. This is bound to greatly accelerate the ADME..

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This article describes a fully automated online solid-phase extraction–liquid chromatography–tandem mass spectrometry (SPE–LC–MS-MS) setup using a mass spectrometer and an electrospray ionization probe for analyzing different groups of polar contaminants in natural waters. The goal was to develop an online SPE method for the quantification of sulfonamide antibiotics, including their acetyl metabolites, as well as for frequently used pesticides (triketones, phenylureas, chloracetanilides, phenoxyacetic acids, amides, and triazines) in ambient waters. The analytical methods were applied successfully for a field study in an agricultural region within the catchment area of Lake Greifensee near Zurich, Switzerland.

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Reproducing analysis conditions is crucial to achieving consistent, accurate results in gas chromatography–mass spectrometry (GC–MS). Valid reproduction demands appropriate application of technique, solid method design, reliable and accurate equipment, and a dedicated team of well-practiced technicians and researchers. But even when all these conditions are met, users can be held back by the more subtle elements in GC–MS operations, such as cutting or changing a column, or setting up the same experiment on different equipment. Even getting the parameters of a test organized so that it can be reproduced elsewhere - in a laboratory across the hall, the country, or the world - can be daunting. Consistent GC–MS results depend upon retention-time reproducibility.

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The study of the interaction mechanism of nucleic acids-CTMAB with AG showed that the enhanced RLS comes from the aggregation of AG on nucleic acids through the bridged and synergistic effect of CTMAB.

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Drug discovery scientists are continually striving to improve productivity and efficiency in their workflows. From early discovery to clinical development, existing workflow bottlenecks represent an opportunity to develop solutions to speed the process and improve productivity. The key requirements for quantitative analysis are precision, accuracy, and linear dynamic range. With any quantitative instrument, the hope is that it will be applicable to a vast range of coumpounds, ruggest, and fast. New mass spectrometry (MS) technologies are being developed that meet these criteria and permit high throughput while enabling its application to areas in which speed limitations previously curtailed its practicality. In particular, in the area of ADME profiling, new MS platforms are becoming available that increase the throughput by at least 25-fold, by combining the speed of matrix-assisted laser desorption ionization (MALDI) with the specificity of triple-quadrupole MS. This is bound to greatly accelerate the ADME..

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Root diseases caused by soilborne plant pathogens are responsible for billions of dollars of losses annually in food, fiber, ornamental, and biofuel crops. The use of pesticides often is not an option to control plant diseases because of economic factors or potential adverse effects on the environment or human health. For this reason, many Americans are now buying pesticide-free organic foods. Organic agriculture has few options for controlling pests and thus must make full use of natural microbial biological control agents in soils that suppress diseases.

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Combined with appropriate selection of instrument components to reduce the sulfur background, ICP-MS using MS/MS with oxygen reaction cell gas can provide accurate low-level analysis of sulfur and sulfur isotope ratios in aqueous and organic matrices. This is useful in applications in life science, clinical research, pharmaceutical development, food safety, environmental monitoring, geochemistry, and petrochemistry.

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PIKE Technologies, Inc.

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Bottled water has become increasingly popular over the past several years for convenience and safety. In some areas where publicly supplied tap water is contaminated or contains bacteria, this assumption is valid. However, in areas with clean tap water, the presence of bottled water can be controversial because it might be less clean than the local tap. This article discusses the analysis of inorganic contaminants in bottled water, including regulated contaminants and bromate. Detection limit considerations and speed of analysis also are discussed.

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Reproducing analysis conditions is crucial to achieving consistent, accurate results in gas chromatography–mass spectrometry (GC–MS). Valid reproduction demands appropriate application of technique, solid method design, reliable and accurate equipment, and a dedicated team of well-practiced technicians and researchers. But even when all these conditions are met, users can be held back by the more subtle elements in GC–MS operations, such as cutting or changing a column, or setting up the same experiment on different equipment. Even getting the parameters of a test organized so that it can be reproduced elsewhere - in a laboratory across the hall, the country, or the world - can be daunting. Consistent GC–MS results depend upon retention-time reproducibility.

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Metabolomics is a developing analytical approach that is growing rapidly in importance as a tool to improve diagnosis and treatment of disease, as well as to speed up the drug development process. Unlike genomics or proteomics, which only reveal part of what might be happening in a cell, metabolomic profiling can give an instantaneous snapshot of the entire physiology of that cell. This article describes the challenges associated with metabolomics research and new tools developed to overcome them.

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The authors discuss progress in near-field IR microspectroscopy using a photothermal probe and show how it can be applied to the spectroscopic characterization of real-world samples.

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The study of the interaction mechanism of nucleic acids-CTMAB with AG showed that the enhanced RLS comes from the aggregation of AG on nucleic acids through the bridged and synergistic effect of CTMAB.

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Root diseases caused by soilborne plant pathogens are responsible for billions of dollars of losses annually in food, fiber, ornamental, and biofuel crops. The use of pesticides often is not an option to control plant diseases because of economic factors or potential adverse effects on the environment or human health. For this reason, many Americans are now buying pesticide-free organic foods. Organic agriculture has few options for controlling pests and thus must make full use of natural microbial biological control agents in soils that suppress diseases.

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Multiline analysis, which consists of using several lines per element to detect positive or negative bias caused by spectral interferences, is an ideal way to use all the information emitted by the plasma and collected by a charge-coupled device detector. However, method development and validation become more complex. Dedicated software has been developed to overcome it, and analysis of geological samples will illustrate their benefit in achieving high reliability of results.

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Assay sensitivity is the lowest concentration at which a targeted analyte can be measured and is often limited by chemical background or co-eluting interferences. FAIMS in combination with liquid chromatography (LC) and zero neutral loss tandem MS was used to remove chemical background and co-eluting interferences from the analysis of linoleic acid in cancer cell extracts. Concentration of endogenous linoleic acid was determined from back-calculation of standard calibration samples fortified with deuterium-labeled linoleic acid. No internal standard was used. LC–MS-MS analysis of the cancer cell extracts resulted in an increase in signal-to-noise ratio of 10-fold. The assay sensitivity was increased 10 times over the traditional LC–MS-MS experiment exclusively due to the new FAIMS technology.

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The authors discuss the use of serial coulometric flow cells coupled online with electrospray ionization mass spectrometry in predictive assays for absorption, distribution, metabolism, excretion, toxicity (ADME/Tox), and stability implemented at early stages of drug discovery.

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Signal-to-noise of a chromatographic peak from a single measurement has been used determine the performance of two different MS systems, but this parameter can no longer be universally applied and often fails to provide meaningful estimates of the instrument detection limits (IDL).

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High-resolution ultrasonic spectroscopy titration analysis is a powerful new tool in research and analytical laboratory work for quantitative measurements of different processes and compounds. Here, the authors explore its potential.