Kargosha K, Ahmadi S H, Mansourian M, Azad J
Chemistry and Chemical Engineering Research of Iran, P.O. Box 14335-186, Tehran, Iran.
Talanta. 2008 Apr 15;75(2):589-93. doi: 10.1016/j.talanta.2007.11.065. Epub 2007 Dec 15.
A direct and reagent free procedure for simultaneous determination of sodium lauryl ether sulfate (SLES), coconut diethanol amide (CDEA) and linear alkylbenzene sulfonate (LABS) in undiluted samples of hand dishwashing liquids has been developed. This determination was carried out by using attenuated total reflectance Fourier transform infrared spectrometry (ATR-FTIR) and multivariate analysis. An implementation of the PLS statistical approach to quantitative analysis of one nonionic and two anionic surfactants was applied to a set of mid-infrared spectra (1305-990 cm(-1)) recorded for commercial detergent samples and ternary standard solutions. An orthogonal calibration design for three components and five levels for standards were employed. Number of factors and scans and also the resolution were optimized. The statistical parameters such as the root mean square error of calibration (RMSEC), root mean square error of cross-validation (RMSECV), standard error of prediction (SEP) and relative standard deviation (R.S.D.) were evaluated. These parameters were obtained as: RMSEC 0.13, 0.20 and 0.14, RMSEV 0.09, 0.17 and 0.04 and SEP 0.12, 0.39 and 0.18 (g per 100 g) for SLES, CDEA and LABS, respectively. R.S.D. for five independent analyses were 1.69 for SLES, 3.76 for CDEA and 1.76 for LABS. The component linear correlation coefficients comparing actual and predicted concentrations of SLES, CDEA and LABS in some real samples were 0.9995, 0.9915 and 0.9974, respectively.
已开发出一种直接且无需试剂的方法，用于同时测定未稀释的餐具洗涤剂样品中的月桂醇聚醚硫酸酯钠（SLES）、椰油二乙醇酰胺（CDEA）和直链烷基苯磺酸盐（LABS）。该测定通过衰减全反射傅里叶变换红外光谱法（ATR-FTIR）和多元分析进行。将偏最小二乘法（PLS）统计方法应用于一种非离子和两种阴离子表面活性剂的定量分析，该方法应用于为商业洗涤剂样品和三元标准溶液记录的一组中红外光谱（1305 - 990 cm(-1)）。采用了针对三种成分和五个标准水平的正交校准设计。对因子数量、扫描次数以及分辨率进行了优化。评估了校准均方根误差（RMSEC）、交叉验证均方根误差（RMSECV）、预测标准误差（SEP）和相对标准偏差（R.S.D.）等统计参数。这些参数分别为：SLES的RMSEC为0.13、0.20和0.14，RMSEV为0.09、0.17和0.04，SEP为0.12、0.39和0.18（每100克克数）；CDEA的RMSEC为0.13、0.20和0.14，RMSEV为0.09、0.17和0.04，SEP为0.12、0.39和0.18（每100克克数）；LABS的RMSEC为0.13、0.20和0.14，RMSEV为0.09、0.17和0.04，SEP为0.12、0.39和0.18（每100克克数）。五次独立分析的R.S.D.分别为：SLES为1.69，CDEA为3.76，LABS为1.76。在一些实际样品中，SLES、CDEA和LABS实际浓度与预测浓度的成分线性相关系数分别为0.9995、0.9915和0.9974。
