Aim: To develop and validate a simple, precise and cost-effective UV- visible spectrophotometric method for the estimation of Ritonavir according to the ICH Q2 (R1) guideline.
Methods: Spiked Ritonavir solution was scanned over UV-visible range for its wavelength of maximum absorbance. Various calibration standards of Ritonavir were prepared, and absorbance was recorded at wavelength of maximum absorbance. Calibration curve of concentration vs. absorbance was plotted and linearity and range was calculated. Various analytical method validation parameters viz. accuracy, precision, LOD, LOQ, robustness and ruggedness were calculated using QC standards. In order to check the performance, pre-validated method was used to estimate the Ritonavir content of marketed formulation.
Results: The wavelength of maximum absorbance for Ritonavir was found to be 255 nm. The correlation coefficient over the concentration range of 30-210 µg/mL was found to be 0.999. Developed UV method was found to be precise during the intra-day and inter-day study and showed percent relative standard deviation in the range of 0.21 to 1.60 & 0.21 to 1.62 respectively. The total percent recovery of Ritonavir was found to be 99.49 to 100.39 %. Developed method was found to be robust and rugged for the intended use. Developed UV-Visible method was successfully used for the estimation of Ritonavir content in marketed formulation of reputed Indian pharmaceutical industry.
Conclusion: A simple, precise and cost-effective UV- visible spectrometry method for the estimation of Ritonavir was developed. The said method was developed using economical percentage of organic phase in aqueous media as solvent. Said validated UV- visible method can be efficiently used for the estimation of Ritonavir in bulk as well as formulation.