Nghiên cứu xây dựng phương pháp định tính, định lượng deoxyarbutin và hydroquinon trong kem bôi da mỹ phẩm bằng HPLC-DAD

A simultaneous analysis procedure for the determination of Deoxyarbutin (dA) and Hydroquinone (HQ) in cosmetic skin creams has been established using High-Performance Liquid Chromatography with Diode Array Detection (HPLC-DAD). The banned substances Deoxyarbutin and Hydroquinone, were extracted from the cream sample matrix by using solvent extraction, followed by cold centrifugation and filtration. The filtrate was subjected to HPLC analysis using a PDA detector under the following conditions: Chromatographic column: Phenomenex Luna C18 (250 x 4.6 mm, 5µm), mobile phase: a 50:50 mixture of methanol and water; flow rate 1 mL/min, detection wavelength: 285 nm. The method validation results indicated that the procedure exhibits high specificity with limits of detection (LOD) of 0.097µg/ml for HQ and 0.190µg/ml and and 0.190 µg/mL for dA. The method also has a low limit of quantification (LOQ) of 0.321 µg/mL for HQ and 0.628 µg/mL for dA, along with a broad linear range of 0.32 µg/mL to 3.2 µg/mL for HQ and 0.63 µg/mL to 6.3 µg/mL for dA. The accuracy is high, ranging from 94.01% to 104.37% for HQ and 97.21% to 99.39% for dA. Repeatability is also satisfactory, with a maximum relative standard deviation (RSD) of 0.376% for HQ and 0.183% for dA, and a maximum RSD for spiking of 2.46% for HQ and 2.98% for dA. The chromatographic analysis time is reasonable, taking 25 minutes per sample injection. The proposed method meets the analytical requirements for detecting low concentrations as outlined by AOAC standards. Keywords: Deoxyarbutin, Hydroquinone, Quantification of banned substances dA, Whitening agents dA, HPLC- dA and HQ.