Methyl sulfate (MeSO4-) salts were explored as thermochemolysis-methylation (TCM) reagents for gas chromatographic (GC) analysis of dipicolinic acid (DPA) as its dimethyl ester (Me2DPA) from bacterial endospores. The reaction was carried out under non-pyrolytic conditions by inserting a small coiled wire filament coated with the sample and reagents directly inside a GC injection port at 290 °C. Above 10 : 1 methyl donor/DPA ratios, alkali metal salts of MeSO4- effected 80-90% conversion of DPA to Me2DPA, which was 10-20 times more active than the same amount of tetramethylammonium hydroxide (TMA-OH) at this temperature.
View Article and Find Full Text PDFA simple device for field sampling and concentration of analytes for subsequent introduction into an injection port for gas chromatographic (GC) analysis has been developed. It consists of a tiny, coiled platinum wire filament (CWF) that is attached to a retractable plunger wire, which fits inside a syringe needle housing. Sampling is accomplished by dipping the end of the CWF in a liquid sample, which is drawn into the wire coil by capillary action, and introducing it into the injection port either before or after allowing the solvent to evaporate.
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