Ethyl 2-methyl-3-(trimethylsil

Quantitation of Cocaine, Benzoylecgonine, Ecgonine Methyl Ester, and Cocaethylene in Urine and Blood Using Gas Chromatography-Mass Spectrometry (GC-MS

, benzoylecgonine-d3, ecgonine methyl ester-d3, and cocaethylene-d3 and buffered with phosphate buffer. The drugs in the sample are extracted by cation-exchange solid phase extraction. The drugs from the solid phase cartridge are eluted and the eluent is dried

Determination of Sulfur Amino Acids, Glutathione, and Related Aminothiols in Biological Samples by Gas Chromatography with Flame Photometric Detection

and lack sensitivity. GC methods based on the conversion into trimethylsilyl (4 ,5 ), neopentylidine (6 ), and N-trifluoroacetyl n -butyl ester (7 ) derivatives lack sensitivity, gives a tailing peak and requires anhydrous derivatization conditions

Quantitation of Homovanillic Acid (HVA) and Vanillylmandelic Acid (VMA) in Urine Using Gas Chromatography-Mass Spectrometry (GC/MS)

(VMA). In the following procedure, urine samples are diluted to give a creatinine concentration of 2 mg/dL. Deuterated internal standards are added to the diluted urine samples followed by acidification using HCl. Ethyl acetate is used to extract HVA