Modeling of chromatographic retention of the selected antiarrhythmics and structurally related compounds in the hydrophilic interactions under the TLC and HPLC conditions

High-performance liquid chromatography (HPLC) plays an important role in testing the pharmaceutically active compounds. In despite of the advantages of HPLC, thin-layer chromatography (TLC) retains its applicability to the different experimental tasks. The experimental conditions which allow hydrophilic interactions in the chromatographic system were tested in the HPLC and TLC systems for ivabradine, its related compounds, diltiazem and verapamil. Under the TLC conditions, retention behavior of the investigated compounds was tested on silica gel modified with cyanopropyl ligands as stationary phase and acetonitrile + methanol containing 25% <i>v</i>/<i>v</i> formic acid. Under the HPLC conditions, we used silica gel modified with cyanopropyl ligands as a column packing and the acetonitrile + 0.25% aqueous solution of formic acid as mobile phase. Retention behavior of the investigated analytes depending on the changing volume fractions of the mobile phase modifier was characterized both for TLC and HPLC data sets by the Soczewiński–Wachtmeister equation. Linear relationships were established between the retention coefficients characterizing the retention mechanism (<i>R</i>_M⁰/<i>m</i>, log<i>k</i>₀/<i>m</i>) and molecular properties of the investigated compounds. The Quantitative Structure Retention Relationship (QSRR) modeling was performed with the use of the stepwise multiple linear regression, in order to select molecular properties which influence retention.高效液相色谱法（High-performance liquid chromatography, HPLC）在药物活性成分的检测中具有重要地位。尽管高效液相色谱法优势显著，但薄层色谱法（thin-layer chromatography, TLC）仍在多样实验任务中保有适用价值。本研究针对伊伐布雷定、其相关化合物、地尔硫卓及维拉帕米，在高效液相色谱与薄层色谱体系中，对可实现亲水相互作用的色谱实验条件进行了测试。在薄层色谱条件下，以氰丙基配体修饰硅胶作为固定相，以含25%（v/v）甲酸的乙腈-甲醇混合溶剂为展开剂，考察了目标分析物的保留行为。在高效液相色谱条件下，则采用氰丙基配体修饰硅胶作为色谱柱填料，以乙腈与0.25%甲酸水溶液的混合体系作为流动相。针对两类体系中分析物保留行为随流动相改性剂体积分数变化的规律，本研究借助索切温斯基-瓦赫特迈斯特方程（Soczewiński–Wachtmeister equation）对高效液相色谱和薄层色谱数据集完成了表征。研究建立了表征保留机制的保留系数（R_M⁰/m、log k₀/m）与目标分析物分子性质之间的线性关联。为筛选影响保留行为的分子性质，本研究采用逐步多元线性回归方法开展了定量结构保留关系（Quantitative Structure Retention Relationship, QSRR）建模。