Optimized RP-HPLC method development and validation for quantification of articaine in bulk and nanostructured lipid carriers using a quality-by-design framework

The goal of the recent study was to establish a simple, precise, reliable, accurate, cost-effective, and stable RP-HPLC method with quality-by-design approach for estimating the amount of articaine in bulk and nanostructured lipid carriers which were developed in house. A fractional factorial design with four factors and eight runs was employed for the initial screening studies. Further optimization of mobile phase ratio and flow rate were conducted using a central composite design. The chromatographic method with reversed-phase chromatographic separation, C-18 column, mobile phase in a mixture of potassium dihydrogen phosphate (KH₂PO₄) and acetonitrile in an 80:20 (% v/v) with a flow rate of 0.8 mL/min and detection wavelength of 273 nm having retention time of 2.876 was developed. The newly developed method was validated as per the guidelines given by International Council for Harmonisation ICH Q2 (R1) which revealed linearity between 10 to 50 µg/mL with r² = 0.995. The % RSD for intra-day precision ranged from 0.2089 to 0.5298, while for inter-day precision, it ranged from 0.1973 to 0.3899. The robustness values were less than 2 %. The percent drug recovered for NLCs was 99.12 %. Further, the limits of detection and quantification (LOQ) were determined to be 2.32 µg/mL and 4.12 µg/mL, respectively. The studies showed that the new approach is simple, selective, rapid, and reproducible for the assessment of pure drug and nanostructured lipid carriers-based formulations.