Ghavami Raouf, Mohammad Sajadi S
Department of Chemistry, Faculty of Science, University of Kurdistan, P. O. Box 416, Sanandaj, Iran.
Chromatographia. 2010 Sep;72(5-6):523-533. doi: 10.1365/s10337-010-1696-5. Epub 2010 Aug 10.
High resolution gas chromatographic relative retention time (HRGC-RRT) models were developed to predict relative retention times of the 209 individual polychlorinated biphenyls (PCBs) congeners. To estimate and predict the HRGC-RRT values of all PCBs on 18 different stationary phases, a multiple linear regression equation of the form RRT = a(o) + a(1) (no. o-Cl) + a(2) (no. m-Cl) + a(3) (no. p-Cl) + a(4) (V(M) or S(M)) was used. Molecular descriptors in the models included the number of ortho-, meta-, and para-chlorine substituents (no. o-Cl, m-Cl and p-Cl, respectively), the semi-empirically calculated molecular volume (V(M)), and the molecular surface area (S(M)). By means of the final variable selection method, four optimal semi-empirical descriptors were selected to develop a QSRR model for the prediction of RRT in PCBs with a correlation coefficient between 0.9272 and 0.9928 and a leave-one-out cross-validation correlation coefficient between 0.9230 and 0.9924 on each stationary phase. The root mean squares errors over different 18 stationary phases are within the range of 0.0108-0.0335. The accuracy of all the developed models were investigated using cross-validation leave-one-out (LOO), Y-randomization, external validation through an odd-even number and division of the entire data set into training and test sets. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1365/s10337-010-1696-5) contains supplementary material, which is available to authorized users.
开发了高分辨率气相色谱相对保留时间（HRGC-RRT）模型，以预测209种多氯联苯（PCBs）同系物的相对保留时间。为了估计和预测所有多氯联苯在18种不同固定相上的HRGC-RRT值，使用了形式为RRT = a(0) + a(1)（邻位氯原子数）+ a(2)（间位氯原子数）+ a(3)（对位氯原子数）+ a(4)（V(M)或S(M)）的多元线性回归方程。模型中的分子描述符包括邻位、间位和对位氯取代基的数量（分别为邻位氯原子数、间位氯原子数和对位氯原子数）、半经验计算的分子体积（V(M)）和分子表面积（S(M)）。通过最终变量选择方法，选择了四个最佳半经验描述符来建立用于预测多氯联苯中RRT的QSRR模型，每个固定相上的相关系数在0.9272至0.9928之间，留一法交叉验证相关系数在0.9230至0.9924之间。在18种不同固定相上的均方根误差在0.0108 - 0.0335范围内。使用留一法交叉验证（LOO）、Y随机化、通过奇偶划分和将整个数据集划分为训练集和测试集进行外部验证来研究所有开发模型的准确性。电子补充材料：本文的在线版本（doi:10.1365/s10337-010-1696-5）包含补充材料，授权用户可获取。
