MEASUREMENT OF A NEW ANTICONVULSANT, (S)-3-(AMINOMETHYL)-5-METHYLHEXANOIC ACID, IN PLASMA AND MILK BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

A specific and sensitive isocratic method for the measurement of a new anticonvulsant, (S)-3-(aminomethyl)-5-methylhexanoic acid, in rat pla sma and milk is described. Following deproteinization, the compound an d internal standard [1-(aminomethyl)cycloheptaneacetic acid] were deri vatized utilizing 2,4,6-trinitrobenzene sulfonic acid and extracted wi th cyclohexane. Analytes were resolved on a 5 mu m Spherisorb ODSII co lumn (250 mm x 4.6 mm) using a mobile phase of 57% acetonitrile in 0.1 M ammonium acetate, pH 4.0. Absorbance was monitored at 350 nm. Limit of quantitation was 1.00 mu g/ml for a 100-mu l aliquot of plasma or milk.