New validated method for piracetam HPLC determination in human plasma

The new method for HPLC determination of piracetam in human plasma was developed and validated by a new approach. The simple determination by UV detection was performed on supernatant, obtained from plasma, after proteins precipitation with perchloric acid. The chromatographic separation of piracetam under a gradient elution was achieved at room temperature with a RP-18 LiChroSpher 100 column and aqueous mobile phase containing acetonitrile and methanol. The quantitative determination of piracetam was performed at 200 nm with a lower limit of quantification LLQ = 2 μg/ml. For this limit, the calculated values of the coefficient of variation and difference between mean and the nominal concentration are CV% = 9.7 and bias% = 0.9 for the intra-day assay, and CV% = 19.1 and bias% = − 7.45 for the between-days assay. For precision, the range was CV% = 1.8 ÷ 11.6 in the intra-day and between-days assay, and for accuracy, the range was bias% = 2.3 ÷ 14.9 in the intra-day and between-days assay. In addition, the stability of piracetam in different conditions was verified. Piracetam proved to be stable in plasma during 4 weeks at − 20 °C and for 36 h at 20 °C in the supernatant after protein precipitation. The new proposed method was used for a bioequivalence study of two medicines containing 800 mg piracetam.