Quinine-loaded polymeric nanoparticles: Validation of a simple HPLC-PDA method to determine drug entrapment and evaluation of its photostability

Abstract

Liquid chromatographic method was developed and validated for quantitative determination of quinine in polymeric nanoparticles. The method was performed using a Waters RP-18 column using a mobile phase consisting of acetonitrile:water:triethylamine (60:40:0.01 v/v/v, and pH aqueous phase adjusted to 3.0 with phosphoric acid). The flow rate was 1.0 mL min-1 and the detection was achieved with a UV-PDA set at 232 nm. The response was linear over a range of 12.0 to 24.0 μg.mL-1 (r = 0.9995). The relative standard deviation values for intra-day and inter-day precision studies were less than 2% and the accuracy was 98.8% to Nc1 and 97.3% to Nc2. The samples free of quinine and quinine-loaded polymeric nanoparticles were subjected to photodegradation conditions. A considerable reduction of degradation of quinine occurred in polymeric nanoparticles. Through these results, it was clear that the nanoencapsulation of quinine protects the drug from degradation by exposure to UV-A light. The analytical method was validated according to International Conference on Harmonization Guidelines and Center for Drug Evaluation and Research.