title: Application of poly(methacrylic acid-ethylene glycol dimethacrylate) monolith microextraction coupled with capillary zone electrophoresis to the determination of opiates in human urine.
abstract: A novel poly(methacrylic acid-ethylene glycol dimethacrylate) (MAA-EGDMA) monolith microextraction method coupled with CZE was proposed for rapidly determining a mixture of opiates comprising heroin, 6-monoacetylmorphine, morphine, codeine, papaverine, and narcotine in human urine. The extraction device contained a regular plastic syringe, the poly(MAA-EGDMA) monolithic capillary tube (530 microm id x 3 cm) and a plastic pinhead, which connected the monolithic capillary tube and the syringe without leakage. In the polymer monolith microextraction, the sample solution was ejected via the monolithic capillary tube by a programmable syringe pump, followed by desorption with an aliquot of appropriate solution, which was collected into a vial for the subsequent analysis by CZE. The best separation was achieved using a buffer composed of 0.1 M disodium hydrogen phosphate (adjusted to pH 4.5 with 1 M hydrochloric acid) and 20% methanol v/v with temperature and voltage of 25 degrees C and 25 kV, respectively. By applying electrokinetic injection with field-enhanced sample stacking, detection limits of 6.6-19.5 ng/mL were achieved. Excellent method of reproducibility was found over a linear range of 80-2000 ng/mL.
authors.affiliation: Department of Chemistry, Wuhan University, Wuhan, P. R. China.
authors.forename: Fang
authors.initials: F
authors.lastname: Wei
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.forename: Yu-Qi
authors.initials: YQ
authors.lastname: Feng
mesh_terms: D002021:Buffers; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D013287:Illicit Drugs / Q000737:chemistry / Q000652:urine*; D009294:Narcotics / Q000737:chemistry / Q000652:urine*; D011109:Polymethacrylic Acids; D015203:Reproducibility of Results; D015813:Substance Abuse Detection / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data
chemical_list: D002021:Buffers; D013287:Illicit Drugs; D009294:Narcotics; D011109:Polymethacrylic Acids; C497090:poly((ethylene glycol dimethacrylate)-co-(methacrylic acid))