双齿键合酰胺极性基团嵌入式C18硅胶色谱固定相的制备与应用OA

The polarity and water resistance of conventional stationary phases for reversed-phase chromatography can be improved by C18 stationary phases prepared by embedding an amide polar group in an octadecyl(C18)group.Single bonded polar groups embedded in C18 stationary phases are susceptible to hydrolysis of the silica-oxygen bond,which shortens the service life.In this paper,bis[3-(trimethoxymethylsilyl)]propylamine was prepared by nucleophilic substitution reaction of bis[3-(trimethoxymethylsilyl)]propylamine with stearoyl chloride to produce bis[3-(trimethoxymethylsi-lyl)]octadecylamido silylating reagent,which was then modified to the surface of silica gel by double-denticle bonding to obtain the amide polar group embedded C18 double-denticle bonded silica gel chro-matographic stationary phase(Sil-AM-C18).Characterization by infrared spectroscopy and nuclear magnetic spectroscopy,combined with elemental analysis data,demonstrated that the bidentate am-ide-modified C18 silane intermediate(AM-C18)had been successfully synthesized and bonded to bare silica gel.The performance of the Sil-AM-C18 column was systematically evaluated,and the results showed that:compared with the traditional C18 stationary phase,the Sil-AM-C18 stationary phase ex-hibited higher column efficiency;due to the embedding of polar amide groups,the Sil-AM-C18 sta-tionary phase had better aqueous phase tolerance,and still possessed a stable retention and symmet-ric peak shapes under the conditions of pure aqueous mobile phase.The double-tooth bonding of Sil-AM-C18 stationary phase has higher hydrolytic stability.The Sil-AM-C18 stationary phase was used for the separation of three types of hydrophilic substances,namely,catechin compounds,anti-tu-berculosis drugs,and vitamin C and its derivatives,and showed superior separation ability com-pared with the traditional C18 stationary phase.