02 March 2007 By:
Dr Margit Geissler, Shuichi Kawana, Katsuhiro Nakagawa
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Inherited metabolic disorders can be detected through analysis of the accumulation of unmetabolized compounds in the human body. For this purpose the blood or urine of a patient is analysed for diagnostic markers with GC–MS.

02 March 2007 By:
Jason Cole, Matthew Lambing, Trisa Robarge
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Routine confirmation and quantification of amphetamine and methamphetamine in urine using gas chromatography and mass spectrometry (GC–MS) for the purposes of workplace drug testing requires methodology that is accurate, precise and reliable. The method described here allows for rapid analysis of these drugs using GC–MS, with excellent specificity, linearity and precision.

02 March 2007 By:
Liming Peng, Michael McGinley
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02 December 2006 By:
Silvia Marten
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Abscisic acid (ABA) occurs in two biologically active enantiomer forms in synthetic preparations. The ABA racemate was resolved here successfully using RP-HPLC and Eurocel 01, a cellulose based chiral stationary phase (CSP). Compared to existing methods using other CSPs, Eurocel 01 produces shorter retention times with comparable selectivity.

02 December 2006 By:
Beth L. Gillece-Castro, Thomas E. Wheat, Jeffrey R. Mazzeo
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The enhanced chromatographic resolution associated with Ultra Performance Liquid Chromatography (UPLC) has been demonstrated for peptide mapping (Mazzeo et al., Biopharm.). The technique improves resolution by a factor of three or more. In addition, the surface chemistry of the BEH Technology particles used in UPLC has proven especially advantageous for peptide mapping; good retention and peak shape are observed with either TFA or formic acid as a modifier. The former modifier is preferred for the best sensitivity with UV detection while the latter improves signal-to-noise in electrospray MS experiments. Glycopeptides, which exhibit microheterogeneity, have also been shown to have enhanced resolution and peak shape. These benefits have been demonstrated for tryptic digests of several proteins.

02 December 2006 By:
Srinivasa Rao, Jim Thayer, Shaofeng Xie
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ProSwift reversed-phase columns are a new family of high resolution monoliths for separating proteins, peptides and other biopolymers.1,2 These monoliths contain an uninterrupted interconnected network of channels and pores with a unique morphology. This structure supports fast analyte mass transfer by convective flow rather than slow mass transfer by diffusion, which predominates in columns packed with porous beads. The uniquely engineered monolithic morphology allows high speed, low back-pressure, high resolution separations, especially for large molecules. This leads to much higher productivity than columns packed with conventional porous silica and polymer beads.

02 December 2006 By:
Liming Peng, Michæl McGingley
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Direct injection of plasma and urine pharmacokinetic/ADME samples has continued to become a more popular technique as researchers attempt to increase sample throughput. The introduction of high performance silica monolith columns like the Onyx monolithic column has made such methods possible, partly as a result of tolerance for matrix contaminants that tend to clog particulate columns.1

02 December 2006 By:
Pranathi Perati, Jeff Rohrer, Dave Thomas
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Azide is commonly used as an antimicrobial in diagnostic preparations and in protein samples. The mechanism of azide's toxicity is poorly understood but its increased presence has made it necessary to quantitatively monitor for its presence in protein samples used for pharmaceutical research as well as in forensic samples.1

02 December 2006 By:
James Kapron, Rohan A. Thakur
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Goal: To improve the accuracy and precision of an LC–MS–MS assay by utilizing high-Field asymmetric waveform ion mobility spectrometry (FAIMS) and highly selective reaction monitoring (H-SRM).
