title: Study of the electrical connection mechanism of sheathless interface for capillary electrophoresis-electrospray ionization-mass spectrometry.
abstract: With the combination of high separation ability of capillary electrophoresis (CE) and strong identification ability of mass spectrometry (MS), CE/MS is becoming a powerful tool for polar and ionic analytes analysis. Different interfaces have been developed to enhance the sensitivity and reliability since the first introduction of CE/MS in 1987. A sheathless porous interface based on a new ions transferring electric connection technique was reported to be with high sensitivity and reliability. In this work, a series of optical and electrochemical experiments were designed to study the electric connection process. The results indicated that closing CE electrical circuit and applying MS spray voltage were achieved by the small ions transferring through the interface porous wall. The new electric connection method significantly enhanced the sensitivity, resolution and stability of the CE/MS analysis. The interface was applied in CE/MS detection of morphine and 6-monoacetylmorphine in urine sample and showed an equal sensitivity to LC/MS. With the significant improvement of sensitivity and stability, the CE/MS with the new interface showed strong potential for the determination of low abundance analytes.
authors.affiliation: Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Biochemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, China.
authors.forename: Cai
authors.initials: C
authors.lastname: Tie
authors.forename: De-Wen
authors.initials: DW
authors.lastname: Zhang
authors.forename: Hong-Xu
authors.initials: HX
authors.lastname: Chen
authors.forename: Sen-Lin
authors.initials: SL
authors.lastname: Song
authors.forename: Xin-Xiang
authors.initials: XX
authors.lastname: Zhang
mesh_terms: D004355:Drug Stability; D019075:Electrophoresis, Capillary / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D007477:Ions; D057230:Limit of Detection; D008956:Models, Chemical; D009020:Morphine / Q000652:urine; D009022:Morphine Derivatives / Q000652:urine; D016062:Porosity; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation* / Q000379:methods; D015813:Substance Abuse Detection / Q000379:methods
chemical_list: D007477:Ions; D009022:Morphine Derivatives; D009020:Morphine; C026979:6-O-monoacetylmorphine