title: Sensitive determination of four β2-agonists in pig feed by capillary electrophoresis using on-line sample preconcentration with contactless conductivity detection.
abstract: In this work, an on-line preconcentration method of field-enhanced sample injection (FESI) was implemented in the determination of four β2-agoinsts terbutaline (TER), procaterol (PRO), formoterol (FOR) and bambuterol (BAM) by capillary electrophoresis coupled with capacitively coupled contactless conductivity detection (CE-C4D). Under optimized conditions the background electrolyte (BGE) was 5mM Tris(hydroxymethyl)aminomethane (Tris) and 10mM citric acid (Cit) at a pH of 3.2 while the sample dilution solution was obtained by methanol. The detection limits (defined as S/N=3) of this method were 0.02mg/L for TER, PRO, FOR, BAM, which were much lower than that of the conventional CE-C4D method without preconcentration procedure, the enhancement factors were greatly improved to be 30-40-fold. The linearity ranges of four β2-agoinsts were 0.1-15mg/L, with good linear correlation coefficients (r2>0.9900). In order to evaluate the application potential of the developed method, real sample from pig feed was analyzed with recoveries of 91.4-106.2%.
authors.affiliation: Department of Chemistry, East China Normal University, 500 Dongchuan Road, Shanghai 200241, PR China.
authors.forename: Fan
authors.initials: F
authors.lastname: Gao
authors.affiliation: Department of Chemistry, East China Normal University, 500 Dongchuan Road, Shanghai 200241, PR China.
authors.forename: Minglei
authors.initials: M
authors.lastname: Wu
authors.affiliation: Department of Chemistry, East China Normal University, 500 Dongchuan Road, Shanghai 200241, PR China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, East China Normal University, 500 Dongchuan Road, Shanghai 200241, PR China.
authors.forename: Guan
authors.initials: G
authors.lastname: Wang
authors.affiliation: Department of Chemistry, East China Normal University, 500 Dongchuan Road, Shanghai 200241, PR China. Electronic address: qjwang@chem.ecnu.edu.cn.
authors.forename: Qingjiang
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Chemistry, East China Normal University, 500 Dongchuan Road, Shanghai 200241, PR China.
authors.forename: Pingang
authors.initials: P
authors.lastname: He
authors.affiliation: Department of Chemistry, East China Normal University, 500 Dongchuan Road, Shanghai 200241, PR China.
authors.forename: Yuzhi
authors.initials: Y
authors.lastname: Fang
keywords: Capillary electrophoresis; Contactless conductivity detection; Field-enhanced sample injection (FESI); β(2)-Agonists