均相合成多重选择性的新型两亲性C22高效液相色谱固定相

Homogeneous Synthesis of Novel Amphiphilic C22 Stationary Phases with Multiple Selectivity

为解决高效液相色谱(HPLC)固定相非均相合成中产物多变和重现性差等问题,该文采用均相合成新方法,制备了既含有二十二碳烷基(C22)、又嵌入脲(U)和/或酰胺(A)强极性基团的两种新型两亲性色谱固定相C22-A和C22-A/U。通过元素分析、核磁等手段,证实制备的两种新型固定相含有碳、氮元素,且碳氮元素比例符合理论值,表明酰胺和脲基极性基团成功键合到硅胶上。通过对多种样品进行色谱分离分析,对两种新型固定相的载体残余硅羟基屏蔽作用、疏水选择性、形状选择性和亲水性等多种性质进行了考察,证实两种新型固定相不但具备作为反相液相色谱(RPLC)的性能,同时也具备亲水相互作用色谱(HILIC)的性能。相较于C18固定相,C22-A和C22-A/U具有更好的形状选择性,双重嵌入的极性基团极大地降低了固定相硅羟基活性。将C22-A和C22-A/U两种固定相应用于几种碱性化合物、雌醇(酮)类化合物的分离,C22固定相在一定程度上解决了传统C18固定相上碱性化合物分离拖尾严重或保留不足的问题,成功实现了对雌醇(酮)类化合物的分离。

In order to solve the variable and irreproducible issues of heterogeneously synthesized chromatographic stationary phases,a new method of homogeneous synthesis was established and used to prepare two newly designed amphiphilic stationary phases,C22-A and C22-A/U,where C22 denotes a long docosyl terminal while U and A denote the strong polar insertions of urea and am⁃ide groups at the initial end,respectively.By the means of elemental analysis and nuclear magnetic spectrum,the two new stationary phases contain nitrogen elements,and the ratio of carbon and nitro⁃gen elements accords with the theoretical value,indicating that the amide and urea-based polar groups are successfully bonded to silica gel.Through the chromatographic separation and analysis of the standard sample and the real sample,the shielding effect on upported silicon hydroxyl,hydro⁃phobic selectivity,shape selectivity and hydrophilicity of the two new stationary phases were investi⁃gated.It is confirmed that the two new stationary phases have amphiphilic properties as reversedphase liquid chromatography(RPLC)and hydrophilic interaction chromatography(HILIC).Com⁃pared with C18 stationary phases,C22-A and C22-A/U own better shape selectivity,and the double embedded polar groups greatly reduce the silica hydroxyl activity of the stationary phase.C22-A and C22-A/U were used for the separation of several alkaline compounds and estrone(ketone)com⁃pounds.The C22 stationary phase solved the problem of serious tailing or insufficient retention of al⁃kaline compounds in the traditional C18 alkyl stationary phase,and successfully realized the separa⁃tion of estrone(ketone)compounds.