ABSTRACT

Objective: To be able to accurately determine the quantity of Pyrazinamide (PZA) in different tablet preparations and human plasma using an Ultra violet detector equipped high performance liquid chromatography (HPLC).

Study Design: Experimental study

Place and Duration of Study: Department of Bioequivalence Studies, University of Veterinary and Animal Sciences Lahore and the Department of Pharmacology, University of Health Sciences, Lahore the from 1^st April 2017 to 31^st March 2018.

Methodology: Two mobile phases were used, the first compromised of disodium hydrogen phosphate buffer having a pH of 6.8 and acetonitrile in the proportion of (95:5) and the second was a combination of aforesaid substances in equivalent proportion (50:50 v/v). The gradient for the first 5 min was exclusively Mobile phase “a” after which 5-6 min Mobile phase “b” was raised from 0 to 100% and was kept at 100% till the completion of the cycle. The flow of mobile phase was kept at 1000 µl/min. Determination of PZA was done using a ultraviolet detector at a wavelength of 238 nm. Amount of sample injected was 40 μl. Procedure was done by using Shizmadu Chromatographic System, Japan equipped with a SIL-20AC HT auto-sampler, SPD-M20A, CTO 20 AC, a LC-20AT VP pump, and CBM 20A controller unit. A C₁₈ column was used as well.

Results: Retention time of PZA was 6.1±2%. Precision was 0.46 to 2.20% relative standard deviation for intra assay and for inter assay we obtained 0.29 to 34.45% RSD for all quality control levels. The overall recovery of PZA was 96.75%.

Conclusion: High selectivity for PZA was seen and no other spikes from drugs present in FDC regimen were observed at the time when PZA is detected in blank plasma samples