电色谱中中性溶质柱内富集研究

On-line Enrichment of Neutral Solute in Capillary Electrochromatography

中性溶质在毛细管电色谱中的富集可以通过调节有机调节剂在运行缓冲溶液和进样区段中的浓度及适当增加进样长度来实现 ,富集作用主要由两种过程控制 ,即进样过程中的自富集作用和运行过程中的一般输运富集作用。采用弛豫理论的研究方法得到了描述富集效果与操作条件关系的理论表达式 ,结果表明 :随进样长度的增加 ,可以有效提高富集效果 ;进样长度对柱效的影响也与有机调节剂的浓度有关 ,当其在两区段中的浓度差别较大时 ,适当加长进样时间并不会对柱效产生太大的影响。对安息香和美芬妥因两种药物的实验研究达到了超过 1 0 0倍的富集效果。

On-line enrichment of neutral solute in capillary electrochromatography (GEC) can be achieved by varying the concentration of organic modifier in sample solution and running buffer, together with extending the injection time. On-line enrichment is mainly controlled by two processes: self-enrichment and transfer enrichment. Based on the method of relaxation theory, an expression, which described the relationship between enrichment factor and running condition, was theoretically derived. Due to this expression, higher enrichment factor can be obtained by extending injection time, and the effect of the injection time on column efficiency depended on the concentration of organic modifier. If there were large difference of concentration of organic modifier in sample solution and naming buffer, proper extending of injection time would have a few effect on column efficiency. The theoretical results were experimentally proved with two drags: benzoin and mephenytoin. The enrichment factor of more than 100 folds was obtained.