title: [Determination of steroids in milk powder and birds' feces by high performance liquid chromatography coupled with evaporative light scattering detector].
abstract: In this paper, a new, simple and rapid method for the analysis of steroids by reversed-phase high performance liquid chromatography (HPLC) coupled with evaporative light scattering detector (ELSD) is presented. A good resolution of the 12 steroids is obtained within 35 min with a gradient elution using a binary mobile phase composed of methanol and water. The analytical column used was 2.0mm x 150mm, packed with BDS (particle size 5microm) and the mobile phase flow rate was 0.2mL/min. Nebulizer gas flow rate and drift tube temperature, the two critical parameters for determining the reproducibility and signal-to-noise ratio of ELSD were 2.00mL/min and 95 degrees C, respectively. The response of the ELSD was non-linear as a result of basic light-scattering principles, the calibration curve by plotting lnY vs lnX (Y, X stand for peak area and concentration, respectively) shows a good linearity in the range of 5-50mg/L with a correlation coefficient higher than 0.99 for individual steroid and with relative standard deviation less than 6.92%. This method has been applied to the determination of steroids in milk powder and birds' feces, solid phase extraction on reverse phase bonded C18 (5mL/500mg) was used to treat the samples efficiently. The recoveries of the steroids were between 84.0%-102.8%.
authors.affiliation: National Chromatographic R. & A. Center, Dalian Institute of Chemical Physics, the Chinese Academy of Sciences, Dalian, 116011.
authors.forename: A
authors.initials: A
authors.lastname: Feng
authors.forename: H
authors.initials: H
authors.lastname: Zou
authors.forename: B
authors.initials: B
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001717:Birds; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D005243:Feces / Q000737:chemistry*; D008892:Milk / Q000737:chemistry*; D013256:Steroids / Q000032:analysis*
chemical_list: D013256:Steroids