Đang chuẩn bị liên kết để tải về tài liệu:
Capillary electrophoresis system using electrochemical detection

Micellar Electrokinetic Capillary Chromatography (MEKC) was employed to the analysis of aniline, phenol and 2,5-dinitrophenol using an end-column amperometric detector with a carbon cloth electrode. The current condition of separation is a solution of 25 mM Na2HPO4, 25 mM Na2B4O7, and 50 mM SDS (pH 9.11); applied voltage, 10 kV; hydrodynamic injection for 15 s at 15 cm; applied potential for electrochemical detection, 500 mV. Absorbance electropherograms is also recorded for comparison. | Journal of Chemistry Vol. 43 4 P. 520 - 523 2005 CAPILLARY ELECTROPHORESIS SYSTEM USING ELECTROCHEMICAL DETECTION Received 6th -Oct.-2004 VU THI THU HA1 IN-JA LEE1 LE Quoc HUNG2 1Dept of Chemistry Dongguk University Gyeongju Gyeongbuk 780-714 Korea institute of Chemistry Vietnamese Academy of Science and Technology summary Micellar Electrokinetic Capillary Chromatography MEKC was employed to the analysis of aniline phenol and 2 5-dinitrophenol using an end-column amperometric detector with a carbon cloth electrode. The current condition of separation is a solution of 25 mM Na2HPO4 25 mM Na2B4O7 and 50 mM SDS pH 9.11 applied voltage 10 kV hydrodynamic injection for 15 s at 15 cm applied potential for electrochemical detection 500 mV. Absorbance electropherograms is also recorded for comparison. I - INtROdUCtION Nowadays application of capillary electrophoresis CE for the separation on analysis in different samples has become increasingly widespread because of its minimal sample volume requirement pl short analysis time and high separation efficiency 1 . Electrophoresis is the movement of electrically charged particles or molecules in a conductive liquid medium usually aqueous under the influence of an electric field. Capillary electrophoresis is typically performed using fuse silica capillary that are 100 cm in length 50 or 75 pm inner diameter i.d and 375 pm outer diameter o.d with voltages of up to 30 kV. The principle of CE system with electrochemical detection is shown in figure 1. When the voltage is applied positive charge cations will migrate toward the negative charged electrode the cathode and the negative charged anions will migrate toward the positively charged electrode the anode. The rates at which they migrate depend on their charge-to-size ration. From that compounds are separated in different migration time. Detection method is one of the most important parameter in CE. A variety of detectors used for CE including UV vis absorbance fluorescence .