METHOD VALIDATION FOR THE ANALYSIS OF NITRENDIPINE ENANTIOMERS IN STANDARD SOLUTION

TF29

Alyne Fávero Galvão and Cristiane Masetto de Gaitani

FCFRP-USP

Nitrendipine is a potent vasodilator with antihypertensive activity whose effects are related to calcium channel inhibiting properties. This drug has one asymmetric center and is administered as a racemate (equimolar enantiomers mixture). Considering the interests in studying the pharmacologic activity of chiral drugs because of differences in pharmacokinetics and pharmacodynamics properties observed between enantiomers, a method was developed and validated for the analysis of nitrendipine enantiomers by HPLC. The resolution of the nitrendipine enantiomers was achieved with a Chiral AGP column (150 x 4 mm I.D., 5 mm particle size), and the mobile phase used was sodium phosphate buffer:isopropanol:acetonitrile (85:7:8, v/v/v), at a flow rate of 0.65 mL/min and detection wavelength of 227 nm. Some validation parameters were studied. Linearity was assessed with concentration of both enantiomers in the range of 2-100 mg/mL (correlation coefficient of 0.993 and 0.9909 for each enantiomer). The precision and accuracy of the method were tested in within-day and between-day studies. The within-day precision and accuracy of the assay were determined by analysis of standard solution (n=3) at concentrations of 10.0, 40.0 and 100.0 µg/mL of each enantiomer. For the evaluation of between-day precision and accuracy the same concentrations were analysed, in triplicate, on five consecutive days. The coefficients of variation for precision studies, as well as the accuracy values, were below 10% at the three concentration levels tested. The quantification limit was 2 mg/mL for both nitrendipine enantiomers.  Keywords: Nitrendipine, validation, enantiomers, HPLC, chiral