一种新型毛细管区带电泳谱图记录模式的研究

The Investigation of a New Recording Mode for Capillary Zone Electrophoresis

提出一种以电通量域模式 (吸收信号对电通量作图 )代替以时间域模式 (吸收信号对时间作图 )记录毛细管区带电泳谱图的新模式 .在阐述了这种记录模式优点的基础上 ,用常用的硼砂和磷酸盐体系在不同的电压和固定电压下分离了 4种药物 ,其迁移时间的相对标准偏差分别在 4 1 .5% (不同电压下 )和 1 .90 %以上 (固定电压 ) ,而相应的电通量的标准偏差都在 1 .0 5%以下 ,这进一步从实验角度证实了电通量域模式记录电泳谱图的优点 :具有极强的抗电场强度波动和温度波动的能力 ,提高了再现性 .以电通量模式记录电泳谱图 ,还可在一定程度上提高峰面积的重现性 .这种记录模式降低了对仪器本身的要求 (高压电压电源的稳定性和恒温装置 ) 。

Since capillary zone electrophoresis emerged as a powerful separation tool, it has been a common practice to record the electropherogram in terms of the time domain. In this recording mode, the migration time often has a considerable change as the potential gradient and temperature inside the capillary do not remain constant in different runs. In this paper, attempt is made to solve the problem in a new way. The electric flux, defined as the amount of electric charge following a cross section of the capillary in a time interval, takes the place of the time as the domain in an electropherogram. At first, it is theoretically demonstrated that as regards to the reproducibility of separation result the use of the electric flux domain is superior to that of the time domain. Then the performances of electric flux domain and time domain are compared in two typical background electrolyte systems, 20 mmol/L Na 2B 4O 7 (pH=9.18) and 10 mmol/L phosphate (pH=8.28). When 10 mmol/L phosphate is used as the background electrolyte and applied voltage varies from 10 to 25 kV(the corresponding temperatures at different voltages are also calculated from our method.), the reproducibility in migration time for berberine hydrochloride, antipyrine, sulfadimidine and sulfadiazine is 41.7%, 41.8%, 41.5% and 42.2%, respectively. In contrast, the reproducibility in electric flux for the above analytes is 1.05%, 0.89%, 0.55% and 0.84%, respectively. The reproducibilities in peak areas obtained from the two recording modes under the same experimental conditions are also compared. The relative standard deviation in area obtained from time mode for berberine hydrochloride, antipyrine, sulfadimidine and sulfadiazine is 42.5%, 44.5%, 42.9%, 45.0%, respectively. In contrast, the reproducibility in electric flux for the above analytes is 3.79%, 2.83%, 3\^02% and 5.19%, respectively. Besides, the relative standard deviations in migration time and electric flux are compared in 12 runs made consecutively at a fixed voltage. The relative standard deviation in electric flux (<0.7%) is lower than that in migration time (>1.8%). [WT5HZ]