Nie Jin-Fang, Wu Hai-Long, Zhu Shao-Hua, Han Qing-Juan, Fu Hai-Yan, Li Shu-Fang, Yu Ru-Qin
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China.
Talanta. 2008 Jun 15;75(5):1260-9. doi: 10.1016/j.talanta.2008.01.026. Epub 2008 Jan 20.
This paper reports a simple, rapid, and effective method for quantitative analysis of 6-methylcoumarin (6-MC) and 7-methoxycoumarin (7-MOC) in cosmetics using excitation-emission matrix (EEM) fluorescence coupled with second-order calibration. After simple pretreatments, the adopted calibration algorithms exploiting the second-order advantage, i.e., parallel factor analysis (PARAFAC) and self-weighted alternating tri-linear decomposition (SWATLD), could allow the individual concentrations of the analytes of interest to be predicted even in the presence of uncalibrated interferences. In the analysis of facial spray, with the external calibration method, the average recoveries attained from PARAFAC and SWATLD with the factor number of 3 (N=3) were 101.4+/-5.5 and 97.5+/-4.1% for 6-MC, and 103.3+/-1.7 and 101.7+/-1.8% for 7-MOC, respectively. Moreover, in the analysis of oil control nourishing toner, the standard addition method (SAM) was suggested to overcome the partial fluorescence quenching of 6-MC induced by the analyte-background interaction, which also yielded satisfactory prediction results. In addition, the accuracy of the two algorithms was also evaluated through elliptical joint confidence region (EJCR) tests as well as figures of merit (FOM), including sensitivity (SEN), selectivity (SEL) and limit of detection (LOD). It was found that both algorithms could give accurate results, only the performance of SWATLD was slightly better than that of PARAFAC in the cases suffering from matrix effects. The method proposed lights a new avenue to determine quantitatively 6-MC and 7-MOC in cosmetics, and may hold great potential to be extended as a promising alternative for more practical applications in cosmetic quality control, due to its advantages of easy sample pretreatment, non-toxic and non-destructive analysis, and accurate spectral resolution and concentration prediction.
本文报道了一种简单、快速且有效的方法,用于采用激发-发射矩阵(EEM)荧光结合二阶校正对化妆品中的6-甲基香豆素(6-MC)和7-甲氧基香豆素(7-MOC)进行定量分析。经过简单预处理后,所采用的利用二阶优势的校正算法,即平行因子分析(PARAFAC)和自加权交替三线性分解(SWATLD),即使在存在未校准干扰的情况下也能预测目标分析物的个体浓度。在面部喷雾分析中,采用外部校准法,PARAFAC和SWATLD在因子数为3(N = 3)时,6-MC的平均回收率分别为101.4±5.5%和97.5±4.1%,7-MOC的平均回收率分别为103.3±1.7%和101.7±1.8%。此外,在控油滋养爽肤水分析中,建议采用标准加入法(SAM)来克服分析物-背景相互作用引起的6-MC的部分荧光猝灭,其也产生了令人满意的预测结果。此外,还通过椭圆联合置信区域(EJCR)测试以及品质因数(FOM),包括灵敏度(SEN)、选择性(SEL)和检测限(LOD),对这两种算法的准确性进行了评估。结果发现,两种算法都能给出准确结果,仅在存在基质效应的情况下,SWATLD的性能略优于PARAFAC。所提出的方法为化妆品中6-MC和7-MOC的定量测定开辟了一条新途径,由于其具有样品预处理简单、无毒无损分析、光谱分辨率和浓度预测准确等优点,有望作为一种有前途的替代方法在化妆品质量控制的更多实际应用中得到扩展。