The Investigation Of Capillary Electrophoresis And Its Application In Medicine Analysis

We import Capillary electrophoresis with electrochemical detection to medicine analysis, and we introduced two genus of on-coupled Capillary electrophoretic separation technic. This article can be separated in four chapter。The development and characteristics of capillary electrophoresis were introduced in chapter one. There is also a brief introduction about the development of amperometric detection, the application of 2D-CE in the drug analysis and the backgrounds of this work.In chapter two, first,capillary zone electrophoresis (CZE) was employed for the analysis of MT and PP using an end-column amperometric detector with a pt electrode. Then, a MECC method for the rapid separation and determination of NT,NM and NF using an end-column amperometric detector uwith pt electrode. The influences of different surfactants (sodium dodecyl sulfate, STS and SLMT), buffer pH and organic modifiers (methanol and acetonitrile) on the determination of the analytes were studied. The optimum conditions of separation and detection are 30 mmol/LNa2B4O7 -1 mmol/LNa2HPO4, which contains 23 mmol/L SDS and 3.3% methanol.At last,capillary zone electrophoresis (CZE) and micelles electrokinetic chromatography (MECC) was on-line hyphenated by a Teflon interface to achieve a two dimensional capillary electrophoresis (2D-CE) system to separate cardiovascular medicine. As a key to the successful coupling of CZE and MECC, a novel interface was developed using Teflon tube. In this paper, the interface was designed and fabricated to integrate CZE with MECC into an on-line 2D CZE-MECC system. A mixed sample of patient serum with 5 cardiovascular medicines was separated to check the effectiveness and reliability of the system. The medicines in this sample were on-line separated in CZE and MECC modes continuously. It is very rapid to perform 2D CZE-MECC separation applying this system. With three electrodes and only one moving high-voltage anode, less than 10min was needed to complete the separation of the sample. Obviously the 2D cooperation will strengthen the comprehensive resolving power and separation efficiency.In chapter three, cafalexin, cafadroxil and trimethoprim was determined by capillary zone electrophoresis with electrochemical detection. The optimum conditions of separation and detection are (pH9.18) for the buffer solution, 16 kV for the separation voltage, 10 kV and 5s for the injection voltage and the injection time, and -0.2 V versus Ag/AgCl reference electrode. The limit of detection is f mol (signal to noise, S/N = 3) and the linear range is about 1.0×10-9-1.0×10-7 mol·L-1 for the three medicine.In chapter four, a novel on-column sequential preconcentration method based on the combination of field-amplified sample injection induced by acetonitrile and pseudo isotachophoresis. With the sequential preconcentration method, a three orders of magnitude detection sensitivity (1,400-fold) increase could be observed compared with the conventional electrokinetic injection method, without compromising separation efficiency and peak shape, and detection limits of 0.1 ng/mL for myosmine and 0.3 ng/mL for anabasine with the conditions selected were achieved. The calibration curves demonstrated good linearity in the concentration ranges 1.3–600 ng/mL for myosmine and 4.9–900 ng/mL for anabasine, respectively.