A micellar capillary electrophoresis（MCE） method based on on-line sweeping technique was（developed） for a determination of trace quinolones,ciprofloxacin ofloxacin and enrofloxacin in pork tissue.The pork tissue s...A micellar capillary electrophoresis（MCE） method based on on-line sweeping technique was（developed） for a determination of trace quinolones,ciprofloxacin ofloxacin and enrofloxacin in pork tissue.The pork tissue samples were deproteinized with trichloroacetic acid and in the running buffer of 20 mmol/L（Na2B4O7）+80 mmol/L sodium dodecyl sulfate（SDS）,pH=9.6,the ciprofloxacin,ofloxacin and enrofloxacin in the sample were successfully separated and detected within 200 s,in a non-coating fused-silica capillary column（48.5 cm×75 μm i.d.,effective length 40 cm） at separation voltage of 18 kV,and the injection pressure of 15×102 Pa,with UV detection at 278 nm.The detection limits of ciprofloxacin,ofloxacin and enrofloxacin were 0.007,0.016 and 0.020 mg/L,and RSD were 2.0%,2.4% and 2.6%,respectively.This method allows of up to 600-fold accumulation concentration of ciprofloxacin and can be used to separate and detect the residuals of trace medicines in animal food.展开更多
A poly(methyl methacrylate)-based capillary electrophoresis microchip, integrated with a microelectrode-based end-column amperometric detection, was described. A short unclosed portion of the separation channel from t...A poly(methyl methacrylate)-based capillary electrophoresis microchip, integrated with a microelectrode-based end-column amperometric detection, was described. A short unclosed portion of the separation channel from the detection cell was used as a working-electrode guide channel. With the aid of a three-dimension micropositioner and an optical microscope, a home-made 6 μm carbon-fiber microdisk electrode(tip diameter of 20 μm) was positioned along the guide channel at 30 μm distance from the channel outlet. With dopamine and catechol the as model analytes, the analytical performance of the system was demonstrated and the detection limit of 1.6×10 -7mol/L for dopamine was achieved, to our knowledge, which is the lowest value than that from published literatures using electrophoresis microchip with end-column amperometric detection.展开更多
文摘A micellar capillary electrophoresis（MCE） method based on on-line sweeping technique was（developed） for a determination of trace quinolones,ciprofloxacin ofloxacin and enrofloxacin in pork tissue.The pork tissue samples were deproteinized with trichloroacetic acid and in the running buffer of 20 mmol/L（Na2B4O7）+80 mmol/L sodium dodecyl sulfate（SDS）,pH=9.6,the ciprofloxacin,ofloxacin and enrofloxacin in the sample were successfully separated and detected within 200 s,in a non-coating fused-silica capillary column（48.5 cm×75 μm i.d.,effective length 40 cm） at separation voltage of 18 kV,and the injection pressure of 15×102 Pa,with UV detection at 278 nm.The detection limits of ciprofloxacin,ofloxacin and enrofloxacin were 0.007,0.016 and 0.020 mg/L,and RSD were 2.0%,2.4% and 2.6%,respectively.This method allows of up to 600-fold accumulation concentration of ciprofloxacin and can be used to separate and detect the residuals of trace medicines in animal food.
文摘A poly(methyl methacrylate)-based capillary electrophoresis microchip, integrated with a microelectrode-based end-column amperometric detection, was described. A short unclosed portion of the separation channel from the detection cell was used as a working-electrode guide channel. With the aid of a three-dimension micropositioner and an optical microscope, a home-made 6 μm carbon-fiber microdisk electrode(tip diameter of 20 μm) was positioned along the guide channel at 30 μm distance from the channel outlet. With dopamine and catechol the as model analytes, the analytical performance of the system was demonstrated and the detection limit of 1.6×10 -7mol/L for dopamine was achieved, to our knowledge, which is the lowest value than that from published literatures using electrophoresis microchip with end-column amperometric detection.
