Objectives: The main objective of the present study was to develop and validate simple, precise, sensitive and accurate RP-HPLC method for the simultaneous estimation of docetaxel (DTX) and ritonavir (RTV) in PLGA nanoparticles (PLGA-NPs).

Methods: The DTX and RTV co-loaded PLGA-NPs were developed by the nanoprecipitation technique. The RP-HPLC method was developed by using (Agilent Compact LC-1220) and Zorbax Eclipse plus C18 column (150×4.6 mm, 3.5 μm, Agilent). Finally, the developed method was validated according to the international conference on harmonization (ICH) guidelines.

Results: The chromatographic separations of DTX and RTV with good resolutions have been achieved by using the mobile phase Acetonitrile: Water (60:40 v/v) containing 0.1% v/v of orthophosphoric acid at a flow rate of 1.0 mL/min, injection volume of 25 µL, and at 239 nm wavelengths. The validated method found to be linear in the range of 0.001-100 μg/mL for DTX and RTV. Detection and quantification limits for DTX were found to be 0.7 and 2.31 μg/mL respectively and for RTV it is 0.3 and 2.87 μg/mL respectively. The % RSD was found to be less than 2% revealing the precision of the developed method. Besides, the recovery rate was observed close to 100% for both the drugs confirming the accuracy of the method. Minor alterations in the chromatographic conditions have revealed robustness and ruggedness of the developed method.

Conclusion: The developed analytical method is simple, precise, sensitive, and reproducible which can be used for the simultaneous estimation of DTX and RTV in the PLGA-NPs.