The Pharmacist

Page: 53–59

Ritonavir, an HIV-1 protease inhibitor, is widely used both as an antiretroviral drug and as a pharmacokinetic enhancer. This study aimed to develop and validate a simple, precise, accurate, robust, and stability-indicating RP-HPLC method for its estimation in bulk and pharmaceutical dosage forms. Chromatographic separation was achieved on a Kromasil C18 column (150 × 4.6 mm, 3.5 µm) using a mobile phase of acetonitrile and 0.2% octane sulfonic acid buffer (20:80 v/v, pH 2.5 adjusted with OPA) at a flow rate of 1.0 mL/min, with detection at 223 nm. Ritonavir eluted at 2.076 min with excellent peak shape (tailing factor 1.12, plate count 9058). The method was linear over 25–150 µg/mL (R² = 0.99988), accurate (99.9–100.1% recovery), precise (%RSD < 1%), and sensitive (LOD 0.60 µg/mL, LOQ 2.00 µg/mL). Forced degradation confirmed its stability-indicating nature. The method is suitable for routine quality control and stability testing.