石英微米晶粒电泳微柱的制备及其电泳分离

Preparation of Electrophoretic Microcolumn Packed with Quartz Microncrystal and Its Application to Electrophoretic Separation

研究了内径2mm石英管填充均匀石英微米晶粒的电泳微柱制备及其电泳分离的可行性。石英微米晶粒用水热法合成。含30%甲醇的1.5mmol/LNa2HPO4为电泳缓冲液(pH11.5),对无需衍生的色氨酸、苯丙氨酸和酪氨酸进行了微柱电泳分离和紫外吸收检测。检出限分别为0.038、0.21和0.20μmol/L;色氨酸的分离效率为4.4×104塔板数/m,电泳微柱的样品容量达到35μL,且有较好的分离重现性。对未填充石英微粒,填充平均粒度360μm石英砂和长9μm石英微米晶粒的电泳微柱的热效应进行了讨论。实验结果表明,在电泳微柱中填充石英微米晶粒可抑制大柱径电泳的热效应,增大样品容量,提高检测灵敏度。此微柱电泳技术可作为现场、实时和便携式电动流动全分析系统的高效分离手段,适合大体积和低浓度样品分析。

The preparation of electrophoretic microcolumn and its application to the electrophoretic separation of amino acids with a 2-mm I. D. fused-silica microcolumn packed with uniform quartz mieroncrystal prepared by hydrothermal synthesis are reported. With 1.5 mmol/L disodium phosphate buffer solution （ pH 11.5 ） containing 30% （V/V） methanol, the tryptophan, phenylalanine and tyrosine were separated by the microcolumn eleetrophoresis and detected by an UV spectrophotometer without derivatization. The limits of detection were 0. 038, 0. 21 and 0. 20 mol/L, respectively. The separation efficiency of tryptophan was 4. 4×10＆4 plates/m. The sample capacity of the electrophoretic microcolumn achieved 35 μL. The precisions of the microcolumn electrophoresis were satisfactory. The thermal effects of the electrophoretic microcolumn that without packing, packed with 360 μm quartz sand and with 9μm length quartz microncrystal were discussed, respectively. It was found that the electrophoretic microcolumn packed with quartz microncrystal was able to inhibit Joule heat, increase sample capacity and enhance detection sensitivity. The microcolumn electrophoresis is one of the high-performance separation techniques for an in-situ, real-time and portable electrokinetic flow analysis system.