LC-MS/MS Method for Simultaneous Estimation of Lopinavir and Ritonavir in Bulk and Dosage Form

Aim

This study introduces a novel simultaneous analytical quantification of Lopinavir (LPV) and Ritonavir (RTV) in drug products by using LC-MS/MS.

Materials and Methods

The present study were carried out on Acquity™ LC system from Waters paired with a triple quadrupole mass spectrometer and employing positive ion mode for optimal mass spectra. The developed method exhibited molecular and product ions for both analytes for improved resolution and signal intensity, choosing an 80:20 v/v mobile phase consists of ACN and 0.1% HCOOH in water. Strong performance was shown by the Acquity BEH C18 column, which ensured distinct peak morphologies and effective elution with retention periods of 1.89 min for LPV and 1.85 min for RTV.

Results

The approach showed remarkable linearity (r2=0.998 for LPV and r2=0.999 for RTV) over the range of 10-150 ng/mL for both medications, confirmed through recovery studies with percentage recoveries of 102.46-110.66% for LPV and 104.50-111.12% for RTV. Selectivity assessments revealed no interference, attesting to the method’s suitability for concurrent quantification. Appropriate %RSD values for peak area and retention time were found by precision evaluations to be between 1.92% and 1.33%. Robustness tests revealed stability with %RSD values for both compounds when the Limit of Quantification (LOQ) and Linit of Detection (LOD) were set at 0.010 g/mL and 0.0003 g/mL, respectively varying between 1.98% and 1.67% for peak area and 1.47% and 0.87% for retention duration. When this approach was used to examine tablet samples that were on the market, the percentage recovery values for LPV is 100.8% and 101.99% for RTV and, underscoring its efficacy for routine quality control testing and establishing it as a precise, sensitive, and robust tool for pharmaceutical analysis.

Conclusion

The suggested method’s results were determined to be acceptable and validated in compliance with regulatory requirements. This approach accurately calculated two pharmaceutical analytes simultaneously.