A new method was developed for pre-concentration and determination of multiple drugs of abuse in human urine using dispersive liquid–liquid microextraction(DLLME)and capillary electrophoresis(CE)with photodiode array...A new method was developed for pre-concentration and determination of multiple drugs of abuse in human urine using dispersive liquid–liquid microextraction(DLLME)and capillary electrophoresis(CE)with photodiode array detection.The method was based on the formation of tiny droplets of an organic extractant in the prepared sample solution using water-immiscible organic solvent(chloroform)dissolved in water-miscible organic dispersive solvent(isopropyl alcohol).The organic phase,which extracted eight drugs of abuse from the prepared urine solution,was separated by centrifugation.The sedimented phase was transferred into a small volume CE auto-sampler vial with 10μL of 1%HCl methanol solution and evaporated to dryness.The residue was reconstituted in lidocaine hydrochloride(internal standard)aqueous solution and introduced by electrokinetic injection into CE.Under the optimum conditions,acceptable linear relationship was observed in the range of 3.0–500 ng/mL with the correlation coefficient(r)of 0.9982–0.9994 for spiked urine samples.The limit of detection(LOD)(S/N=3)was estimated to be 1.0 ng/mL.A recovery of 75.7%–90.6%was obtained for spiked samples.The mean relative error(MRE)was within±7.0%and the relative standard deviation(RSD)was less than 6.9%.The proposed DLLME-CE procedure offers an alternative analytical approach for the sensitive detection of drugs of abuse in real urine samples.展开更多
A novel method for the determination of two quinolone drugs norfloxacin （NOR） and levofloxacin （LVX） was described by capillary electrophoresis with electrochemiluminescence detection. The good relationship （r ≥...A novel method for the determination of two quinolone drugs norfloxacin （NOR） and levofloxacin （LVX） was described by capillary electrophoresis with electrochemiluminescence detection. The good relationship （r ≥ 0.9991） between peak area and concentration of analytes was established over two orders of magnitude. The limits of detection （LOD, S/N = 3） in standard solution are 4.8 × 10^-7 mol/L for NOR and 6.4 × 10^-7 mol/L for LVX, respectively. The limits of quantitation （LOQ, S/N = 10） in real human urine samples are 1.2 × 10^-6 mol/L for NOR and 1.4 × 10^-6 mol/L for LVX, respectively. The present method was successfully applied to the determination of NOR and LVX in human urine and the studv of oharmacokinetics of NOR.展开更多
基金The work was supported by the Programme of Outstanding Talents in the New Century in Universities of Fujian,ChinaYoung Scientific Natural Science Foundation of Universities in Fujian.
文摘A new method was developed for pre-concentration and determination of multiple drugs of abuse in human urine using dispersive liquid–liquid microextraction(DLLME)and capillary electrophoresis(CE)with photodiode array detection.The method was based on the formation of tiny droplets of an organic extractant in the prepared sample solution using water-immiscible organic solvent(chloroform)dissolved in water-miscible organic dispersive solvent(isopropyl alcohol).The organic phase,which extracted eight drugs of abuse from the prepared urine solution,was separated by centrifugation.The sedimented phase was transferred into a small volume CE auto-sampler vial with 10μL of 1%HCl methanol solution and evaporated to dryness.The residue was reconstituted in lidocaine hydrochloride(internal standard)aqueous solution and introduced by electrokinetic injection into CE.Under the optimum conditions,acceptable linear relationship was observed in the range of 3.0–500 ng/mL with the correlation coefficient(r)of 0.9982–0.9994 for spiked urine samples.The limit of detection(LOD)(S/N=3)was estimated to be 1.0 ng/mL.A recovery of 75.7%–90.6%was obtained for spiked samples.The mean relative error(MRE)was within±7.0%and the relative standard deviation(RSD)was less than 6.9%.The proposed DLLME-CE procedure offers an alternative analytical approach for the sensitive detection of drugs of abuse in real urine samples.
基金the National Natural Science Foundation of China(No.20575056)Henan Innovation Project for University Research Talents(No.2005126).
文摘A novel method for the determination of two quinolone drugs norfloxacin （NOR） and levofloxacin （LVX） was described by capillary electrophoresis with electrochemiluminescence detection. The good relationship （r ≥ 0.9991） between peak area and concentration of analytes was established over two orders of magnitude. The limits of detection （LOD, S/N = 3） in standard solution are 4.8 × 10^-7 mol/L for NOR and 6.4 × 10^-7 mol/L for LVX, respectively. The limits of quantitation （LOQ, S/N = 10） in real human urine samples are 1.2 × 10^-6 mol/L for NOR and 1.4 × 10^-6 mol/L for LVX, respectively. The present method was successfully applied to the determination of NOR and LVX in human urine and the studv of oharmacokinetics of NOR.
