研究制备了1.2μm放射型核壳色谱填料,并对其表面进行了键合C18的改性,通过匀浆填充法制备了总长度为350 mm(固定相有效填充长度为70 mm)、内径为100μm的毛细管色谱柱,应用加压毛细管电色谱(pCEC)法考察了硫脲和萘在该色谱柱上的分离性能,同时讨论了流动相中有机相的比例、缓冲液的浓度、pH值、线性流速及施加电压对分离度的影响。实验结果表明,该新型核壳色谱填料在乙腈水体系中分离硫脲和萘时,表现出典型的反相色谱性能,当含有10 mmol/L磷酸的70%(v/v)乙腈水溶液为流动相、缓冲液pH为7.2、施加电压为-10kV时,柱效最高;在最佳线性流速为1 mm/s时,能够在8 min内实现8种中性物质的基线分离,且峰形较好,其中二苯甲酮的柱效高达19 072块/m。该研究表明1.2μm新型放射型核壳色谱填料适用于pCEC法的分离分析。
Silica microsphere packing material with fibrous shells(1. 2 μm)was successfully synthesized and bonded with octadecylsilane functionality. These stationary phase particles were packed into fused-silica capillary with 100 μm i. d. for a total length of 350 mm(70 mm effective length), which was evaluated for pressurized capillary electrochromatography(pCEC). The efficiency of the C18 reversed-phase column was characterized through the theoretical plates of thiourea and naphthalene. The effects of experimental parameters such as the content of acetonitrile in the mobile phase,the concentration of the buffer solution,the pH value of the mobile phase,the flow rate,the applied voltage and the on-column efficiency were investigated. The results showed a typical reversed-phase chromatographic performance. The eight neutral compounds were baseline separated within 8 min and the column efficiency as high as 190 792 plate/m for benzophenone was obtained with the optimal conditions of 10 mmol/L phosphate buffer(pH 7. 2)in 70%(v/v)acetonitrile aqueous solution at an appliednegative voltage of 10 kV and a supplementary pressure of 1. 66 × 107 Pa. The optimal linear velocity was 1 mm/s. The research work confirmed the feasibility of using 1. 2 μm silica microsphere packing material with fibrous shells as a novel stationary phase for pCEC.