Hinokitiolis frequently added to personal care products as an antibacterial agent. We previously established an HPLC-UV method for determination of hinokitiol in skin lotion after pre-column derivatization with 4-fluo...Hinokitiolis frequently added to personal care products as an antibacterial agent. We previously established an HPLC-UV method for determination of hinokitiol in skin lotion after pre-column derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole. However, the labeling reagent is expensive, and derivatives of degradation products of parabens, which may be added to skin lotion as general preservatives, interfered with the peak of the hinokitiol derivative. In this study, the concentration of hinokitiol in skin lotions was determined by HPLC with a visible light detector (450 nm) after pre-column derivatization with 4-(dimethylamino)azobenzene-4’-sulfonyl chloride (Dabsyl-Cl), a more economical reagent. A standard curve was obtained after derivatization with Dabsyl-Cl in borate buffer (pH 9.5) at 55°C for 10 min. The retention time of Dabsyl-hinokitiol was 6.8 min. The calibration plot was linear in the range of 1.25 to 40 μg/mL with a r2 value of 0.9991, and the lower limit of quantification and detection were 0.60 μg/mL (absolute amount of 0.86 ng/20μL injection, signal-to-noise ratio of 10:1) and 0.18 μg/mL (absolute amount of 0.26 ng/20μL injection, signal-to-noise ratio of 3:1), respectively. The coefficient of variation was less than 8.8%. Seven Dabsyl-paraben derivatives showed little interference with the peak of Dabsyl-hinokitiol. The developed system was used to determine the content of hinokitiol in two skin lotions. Addition-recovery tests gave satisfactory results.展开更多
文摘Hinokitiolis frequently added to personal care products as an antibacterial agent. We previously established an HPLC-UV method for determination of hinokitiol in skin lotion after pre-column derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole. However, the labeling reagent is expensive, and derivatives of degradation products of parabens, which may be added to skin lotion as general preservatives, interfered with the peak of the hinokitiol derivative. In this study, the concentration of hinokitiol in skin lotions was determined by HPLC with a visible light detector (450 nm) after pre-column derivatization with 4-(dimethylamino)azobenzene-4’-sulfonyl chloride (Dabsyl-Cl), a more economical reagent. A standard curve was obtained after derivatization with Dabsyl-Cl in borate buffer (pH 9.5) at 55°C for 10 min. The retention time of Dabsyl-hinokitiol was 6.8 min. The calibration plot was linear in the range of 1.25 to 40 μg/mL with a r2 value of 0.9991, and the lower limit of quantification and detection were 0.60 μg/mL (absolute amount of 0.86 ng/20μL injection, signal-to-noise ratio of 10:1) and 0.18 μg/mL (absolute amount of 0.26 ng/20μL injection, signal-to-noise ratio of 3:1), respectively. The coefficient of variation was less than 8.8%. Seven Dabsyl-paraben derivatives showed little interference with the peak of Dabsyl-hinokitiol. The developed system was used to determine the content of hinokitiol in two skin lotions. Addition-recovery tests gave satisfactory results.
