Validation of a method for measuring rifampicin plasma drug concentration in tuberculosis patients

Abstract

Rifampicin is a first-line drug used in the management of tuberculosis (TB) due to its sterilizing effect that targets the bacteria responsible for the disease. This study modified and validated a method for quantitatively determining rifampicin plasma drug concentration of TB patients through High Performance Liquid Chromatography Ultraviolet Visible detection. The analytic method modified from a standard method was validated for linearity, coefficient of variation, intra-day and inter-day precision, and recovery rate. The retention time of rifampicin was reduced from 18.3 to 3.1 minutes after the method was modified. To validate the method, the coefficient of determination was determined for the linearity to be between 0.975 and 0.998, the coefficient of variation ranged between 2.8% to 15.5% for both intra-day and inter-day precision. Recovery rates ranged between 87% and 125%. The results indicated that the analytical method developed was valid, precise and feasible, and could be useful for quantitatively determining rifampicin plasma drug concentration in TB patients.