Analisis Asam Valproat dalam Plasma Secara Kromatografi Gas

Valproic acid is an anticonvulsant drug that works by increasing the levels ofγ-aminobutyric acid (GABA). Determination of valproic acid is quite difficultbecause it has no chromophore groups in its structure. Aa analytical method usinggas chromatography (GC) with flame ionization detector for the determination ofvalproic acid in human plasma has been developed and optimized. Valproic acid wasextracted from plasma by liquid-liquid extraction method using diethyl ether. Theoptimum analysis conditions for valproic acid in plasma were achieved by regulatedgas chromatography injector and detector at a temperature of 250oC and temperatureprogramming with an initial temperature of 70oC and 5oC temperature increasingper minute until a temperature of 100oC, then held for 1 minute. Then the temperaturewas increased by 2°C per minute until the column temperature to 150oC. Theoptimum conditions of analysis took 32 minutes. In the concentration range from40.0 to 100.0 µg/mL yielded a linear calibration curve with correlation coefficient (r)of 0.9894. Accuracy (% diff) of this method was -13.67% to 12.33% with precision(CV) between 9.33% to 14.92%, and relative recovery test was 86.33% to 112.33%.