BRIEFS
The GTi Advantage Don't Separate Your Biomolecules Without It!
T
he LKB "Bioseparation System" designed to purify and separate Biomolecules has the GTi Advantage. It assures highest yields of biological activity possible, by preventing heavy metals contamination. Corrosion of injectors, pumps and other fluidics, commonly caused by halide salts and popular reversed phase solvents is completely eliminated. All system components are made of Glass, Titanium and other inert materials thereby eliminating any concerns about loss of activity or frequent maintenance. The GTi "Bioseparation System" to your Advantage by:
performs
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forming single-pump gradients
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providing full system control
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delivering precise and accurate solvent flows from 0.01 to 5ml/min.
Don't be concerned about a high price either, since the "added advantage" only adds value to performance, it does not add to the cost. Performance made affordable Pharmacia LKB Biotechnology Inc.
Pharmacia Pharmacia LKB Biotechnology Piscataway, New Jersey 08854 For Technical Information: (800) 526-3618 In NJ (201) 457-8459 305 F CIRCLE 132 ON READER SERVICE CARD
548 A · ANALYTICAL CHEMISTRY, VOL. 60, NO. 9, MAY 1, 1988
Utility of Ion Source Pretreatment with Chlorine-Containing Compounds for Enhanced Performance in Gas Chromatography/ Negative Ionization Mass Spectrometry 911 Substantial enhancements in electron-capture negative-ion mass spectra are observed for several classes of compounds following ion source pretreatment with CC14. Results suggest that chlorine atoms in some form are stored on ion source walls and can react with unsaturated molecules to form highly electrophilic species. Daniel B. Kassel, Kathleen A. Kayganich, J. Throck Watson, and John Allison*, Department of Chemistry, Michigan State University, East Lansing, Mich. 48824 Anal. Chem., 60 (1988) Accurate Mass Measurements on Daughter Ions from Collisional Activation in Fourier Transform Mass Spectrometry 917 Accurate mass measurements with errors in the low-ppm range are made on parent and daughter ions from CAD of several organic compounds and mixtures, using a dual-cell FT/MS and pulsed-valve introduction of the collision gas. The dual-cell geometry facilitates complex mixture analysis by permitting high-resolution measurements and by isolating the daughter ions from reactive neutrals. Robert B. Cody, Nicolet Analytical Instruments, 5225-1 Verona Road, Madison, Wis. 53711 Anal. Chem., 60 (1988) Evaluation of a Microwave-Induced Plasma as a Soft Ionization Source in Mass Spectrometry 923 A microwave-induced rare gas plasma produced by surface wave propagation is used at low pressure and moderate power as a soft ionization source in quadrupole mass spectrometry. Emmanuelle Poussel and Jean Michel Mermet*, Laboratoire des Sciences Analytiques, Université Claude Bernard—Lyon I, 69622 Villeurbanne Cedex, France, and Daniel Deruaz, Laboratoire d'Etudes Analytiques et Cinétiques du Médicament, 8 Avenue Rockefeller, Université Claude Bernard—Lyon I, 69008 Lyon, France, and Claude Beaugrand, Nermag, 49 quai du Halage, 92500 Rueil Malmaison, France Anal. Chem., 60 (1988) Identification of the Position and the Stereochemistry of the Double Bond in Monounsaturated Fatty Acid Methyl Esters by Gas Chromatography/Mass Spectrometry of Dimethyl Disulfide Derivatives 928 The procedure described is suitable for the determination of compounds encountered in natural environments at the nanogram level. An application is presented for the determination of planktonic and bacterially derived fatty acids in marine sediments. Pierre Scribe*, Jean Guezennec, Jacques Dagaut, Claude Pepe, and Alain Saliot, Laboratoire de Physique et Chimie Marines, Université Pierre et Marie Curie, UA CNRS No. 353, tour 24, 4 Place Jussieu, 75252 Paris Cedex 05, France, and Direction de l'Ingénierie et de la Technologie, IFREMER-COB, B.P. 337, 29273 Brest Cedex, France Anal. Chem., 60 (1988)
