Special Issues-10-01-2009

Inductively coupled plasma–mass spectrometry (ICP-MS) is a mature method that offers reliable measurements across almost the entire periodic table. It has been established as the key methodology for investigating elemental concentrations, which play a central role in biological, environmental, chemical, and industrial processes. ICP-MS is capable of performing multielemental analyses in a single analytical run, achieving an overall productivity of more than 50 samples/h. The method also delivers lower detection limits compared to graphite furnace atomic absorption (GFAA) or inductively coupled plasma–optical emission spectrometry (ICP-OES).

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Metabolite profiling in drug discovery can contribute significantly at the lead optimization stage in two main application areas. The first is the identification of major metabolites, which provides medicinal chemists with information on the metabolic "soft spots." These soft spots are locations on the molecule particularly susceptible to metabolic modification, which can contribute to high pharmacokinetic clearance. This information then can be used to optimize the structure of a lead compound or chemical series to slow the rate of metabolism and therefore reduce hepatic clearance. This improves the absorption, distribution, metabolism, and excretion (ADME) properties of the compound, such as bioavailability, exposure (as measured by area under the curve), and half-life. Through iterative optimization of the structure and timely generation of metabolism data following each structural modification, pharmacokinetic properties can be improved while maintaining activity against the therapeutic target.

The use of medicinal herbs as alternative treatment methods continues to grow. With this escalating use has come an increasing interest in determining the chemical compositions of these herbs in order to obtain a better understanding of their makeup and effects. In this study, Flos Chrysanthemi, a commonly used traditional Chinese medicine that has been cultivated for centuries, was analyzed to identify the main flavone compositions in one original breed of Flos Chrysanthemi (Hangbaiju) in China.

Both Chinese ginseng and Korean ginseng are similar plant species and undergo similar handling procedures when harvested and processed for sale. Despite their similarities, Korean ginseng commands a higher price than Chinese ginseng on the open market and is believed to produce different clinical effects than Chinese ginseng. Chinese researchers are now employing new techniques on the two varieties of ginseng to understand their chemical differences. HPLC/UV-based strategies for distinguishing the two types of ginseng have proven to be mostly ineffective due to lack of resolution. Using UltraPerformance liquid chromatography/orthogonal acceleration (oa)–TOF mass spectrometry and exact mass measurement, the authors developed a high-resolution method using multivariate statistical analysis for separating and identifying differences between Chinese ginseng and Korean ginseng at the molecular level.

Inductively coupled plasma–mass spectrometry (ICP-MS) is a key analytical tool in many laboratories. It is used for elemental determinations across a wide range of analyses, including environmental, semiconductor, food safety, geological, chemical, petrochemical, nuclear, clinical, forensic, and research applications. Since the early publications during the development of ICP-MS, it has been apparent that one of the key limitations of the technique was the presence of molecular ions that overlap the preferred isotopes of several analytes. These molecular ions are typically called "polyatomic" ions, and are derived from combinations of the elements present in the plasma, the solvent and the sample matrix.

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October 09, 2009

No Slowdown in Scientific Innovation

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October 09, 2009

Here we present an updated glossary of industry terms - a handy guide for the seasoned analyst as well as those new to the field.

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October 09, 2009

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