Hao Yong, Cai Wensheng, Shao Xueguang
Research Center for Analytical Sciences, College of Chemistry, Nankai University, Tianjin, 300071, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2009 Feb;72(1):115-9. doi: 10.1016/j.saa.2008.08.011. Epub 2008 Sep 3.
Near-infrared diffuse reflectance spectroscopy (NIRDRS) has been proved to be a convenient and fast quantitative method for complex samples. The high detection limit or the low sensitivity of the method, however, is a big problem obstructing its application in the analysis of low concentration samples. A strategy for quantitative determination of low concentration samples was developed by using NIRDRS. The method takes an adsorbent as a substrate for gathering the analytes from a solution, and uses the multivariate calibration technique for quantitative calculation. So, the detection limit can be improved and the interferences can be eliminated when complex samples are analyzed. Taking benzoic and sorbic acids as the analyzing targets and the alumina as the adsorbent, partial least squares (PLS) model is built from the NIRDRS of the adsorbates. The results show that the concentrations that can be quantitatively detected are as low as 0.011 and 0.013 mg mL(-1) for benzoic and sorbic acids, respectively, and the co-adsorbates do not interfere each other.
近红外漫反射光谱法（NIRDRS）已被证明是一种用于复杂样品的便捷、快速的定量方法。然而，该方法的高检测限或低灵敏度是阻碍其在低浓度样品分析中应用的一个大问题。通过使用近红外漫反射光谱法开发了一种定量测定低浓度样品的策略。该方法以吸附剂为底物从溶液中富集分析物，并使用多元校准技术进行定量计算。因此，在分析复杂样品时可以提高检测限并消除干扰。以苯甲酸和山梨酸为分析对象，以氧化铝为吸附剂，根据被吸附物的近红外漫反射光谱建立偏最小二乘法（PLS）模型。结果表明，苯甲酸和山梨酸的定量检测浓度分别低至0.011和0.013 mg mL(-1)，且共吸附物之间互不干扰。
