GC Determination of Nopinic Acid in the Products of Its Synthesis

Nopinic acid was synthesized from β-pinene by oxidation with KMnO4 in alkaline solution,and amount of nopinic acid in the reaction products was determined by gas chromatograph with the SE-30/chromosorb W/AW separation column (0.25-0.175 mm).By use of the proposed column,nopinic acid was nicely separated from the by-products,and well-difined symmetrically shaped peak of nopinic acid was obtained.Linear relationship between peak area and mass concentration of nopinic acid was obtained in the range from 15.0 to 60.0 g·L-1,with detection limit (S/N=3) of 3.5 g·L-1.Recovery and precision of the method were tested,giving value of RSD (n=5) of 1.8% and values of recovery in the range of 90%-98%.