Validation of a Simultaneous Determination Procedure for Alpha Arbutin and Nicotinamide in Cosmetic Serum Using High-Performance Liquid Chromatography with a Photodiode Array Detector

Abstract

This study was conducted to validate an analytical procedure for the simultaneous determination of alpha arbutin and nicotinamide in cosmetic serum using high-performance liquid chromatography with a photodiode array detector (HPLC-PDA). Chromatographic separation was performed on an InertSustain C18 column (250 × 4.6 mm, 5 µm) using a mobile phase of methanol - water (20:80, v/v) at a flow rate of 1.0 mL/min. Detection was carried out at 220 nm and the column temperature was maintained at 30 ^oC. The analytical procedure was validated in accordance with the International Council for Harmonisation (ICH) guideline with respect to system suitability, specificity, linearity and range, accuracy, precision, limit of detection (LOD), and limit of quantification (LOQ). The results demonstrated that the analytical procedure was specific, with complete separation of the alpha arbutin and nicotinamide peaks without interference from the sample matrix. Good linearity was achieved over the concentration ranges of 12.08 - 28.20 µg/mL for alpha arbutin and 30.18 - 70.42 µg/mL for nicotinamide, with correlation coefficients (R²) of 0.9998 for both analytes. Accuracy ranged from 98.12% to 100.79% recovery, and precision showed relative standard deviation (RSD) values below 2.0%. The LOD and LOQ were 0.369 and 1.120 µg/mL for alpha arbutin, 0.785 and 2.379 µg/mL for nicotinamide, respectively. The validated analytical procedure can be applied to the quality control of cosmetic products containing alpha arbutin, nicotinamide, or both, with similar excipient compositions.