Quantitative structure-retention relationships in doping control

Regression equation modelling was used for the correlation of gas chromatographic relative retention times t_RR of anabolic steroids, stimulants and narcotics with their molecular characteristics in order to create a model for the prediction of t_RR values of unanalysed molecules. Predicting chromatographic retention parameters is one of the main goals of the quantitative structure-retention relationships (QSRR) methodology. To be performed, QSRR studies require two tools; a methodology for the extraction of the structural characteristics and a statistical program for the correlation of these characteristics with the chromatographic data.     

Computational and QSAR study of the alkylnaphthyl ketones adsorption on silver-ion stationary phase

The chromatographic behaviour of α- and β- alkylnaphthyl ketones at different temperatures on the silver-loaded stationary phase is described based on the QSRR model. Complexation via an oxygen atom is favoured over the interaction through the aromatic fragment. The QSRR model and DFT/MP2 studies suggest that retention times of alkylnaphthyl ketones on silver-containing stationary phases are determined primarily by the dipole moment, length of the alkyl substituent and concentration of modifier in the mobile phase.     

Quantitative structure/retention relationships in affinity chromatography.

Affinity chromatography (AC) followed by quantitative structure/retention relationships (QSRR) analysis provides information on both the analytes and the macromolecules forming the stationary phases. QSRR equations derived for test series of analytes (often drugs) are interpreted in terms of structural requirements of the specific binding sites on macromolecules. Chromatographically demonstrated differences in analyte/macromolecule interactions may be relevant to molecular pharmacology and rational drug design. Multiple regression analysis of appropriately designed sets of affinity-chromatographic data may help increase the speed and efficiency of search as for new drugs and reduce the need for in vivo screening. Specific high-performance affinity-chromatographic separations can be optimized by rational selection of chiral columns, the characteristics of which are provided by QSRR.     

Capillary gas-liquid chromatographic separation of bile alcohols.

Gas-liquid chromatographic separation of C23, C24, C25, C26, and C27 bile alcohols with either 3 alpha, 7 alpha-dihydroxylated or 3 alpha, 7 alpha, 12 alpha-trihydroxylated ring system on two capillary columns, CP-Sil-19 CB and CP-Sil-5 CB, is described. Bile alcohols with two ring hydroxyl groups at 3 alpha- and 7 alpha-positions consistently showed larger retention times on CP-Sil-19 CB columns and smaller retention times on CP-Sil-5 CB columns than the corresponding bile alcohols with three ring hydroxyl groups at 3 alpha-, 7 alpha-, and 12 alpha-positions. Resolutions of all bile alcohols were better on CP-Sil-19 CB columns; however, we hope that the gas-liquid chromatographic characteristics on the two columns will be useful for better identification of bile alcohols in biological fluids.     

灯盏花挥发性组分结构与保留时间关系研究

通过对有机化合物非氢原子进行分类、参数化染色、建立非氢原子之间的关系得到新的结构描述符.对灯盏花的64种挥发性有机化合物结构进行了参数化表征,运用多元线性回归(MLR)和偏最小二乘回归(PLS)方法构建了化合物结构与色谱保留时间的关系模型.通过“留一法”交互检验对模型的稳定性进行了评价,利用外部样本集对模型的预测能力进...