Preparation Of Nano Latex-coated Open-tubular Column And Application In Capillary Electrophoresis

Electroosmotic flow (EOF) is one of the most important nature in the capillaryelectrophoresis (CE). It can control the migration speed and direction of thecomponents being tested, thereby affecting the column efficiency, resolution andreproducibility, so it is crucial to control the EOF in CE. In the present work,dimethylethanolamine aminated polychloromethyl styrene nano-latex (DMEAPL),DMEAPL coated capillary column (ccc-DMEAPL) and trimethylamine aminatedpolychloromethyl styrene nano-latex (TMAPL), TMAPL coated capillary column(ccc-TMAPL) were prepared. This paper developed the field-amplified samplestacking open-tubular capillary electrochromatography (FASS-OT-CEC) methods fordetermination of complex substances in biological samples by nano-latex coatedopen-tubular columns.1．Two kinds of open-tubular column ccc-DMEAPL and ccc-TMAPL wereprepared choosing DMEAPL and TMAPL as the stationary phase respectively. Theinwall of open-tubular columns were characterised from the scanning electronmicroscopy(SEM) image, infrared, the values, stability and repeatability of EOF，andthe EOF values obtained from the coated column were more steady and lower thanthe bare columns, even reversed with ccc-TMAPL. These proved that the modifiedcolumns were prepared successfully.2. A novel analysis method for four TCs in pig plasma was constructed byFASS-OT-CEC with ccc-DMEAPL. The optimized conditions were as follows, BGE:10mmol/L Na2HPO4+15mmol/L citric acids (pH3.2); separation voltage:18kV;detection wavelength:270nm; column temperature:25oC; water-plug:30mbar×10s; electrokinetic injection:10kV×20s. The four TCs were achieved the baselineseparation in8min on the ccc-DMEAPL column. LODs for TCs were between3.0ng/mL and7.0ng/mL, and the overall recoveries were more than80%. Based on theabove analytical parameters, it can be seen that the proposed FASS-OT-CEC wassimple, sensitive and accurate.3. A sensitive and practical method for trace nitrite and nitrate in biological samples was developed by FASS-OT-CEC with ccc-TMAPL. The optimizedconditions were as follows, BGE:20mmol/L Tris+13.5mmol/L HClO4(pH7.87);separation voltage:-20kV; detection wavelength:214nm; column temperature:25oC; water-plug:50mbar×30s; electrokinetic injection:-13kV×30s. Both nitrateand nitrite were achieved the baseline and rapid separation on the ccc-TMAPLcolumn. The LODs for nitrite and nitrate both were1.0ng/mL. The proposedsensitive FASS-OT-CEC analytical methods for trace nitrate and nitrite hold thepromise of practical applications in a wide array of biological analyses, clinical andpathophysiology studies of the disease related with NO hyperproduction andmetabolites.