title: A simple and compact fluorescence detection system for capillary electrophoresis and its application to food analysis.
abstract: A novel fluorescence detection system for CE was described and evaluated. Two miniature laser pointers were used as the excitation source. A Y-style optical fiber was used to transmit the excitation light and a four-branch optical fiber was used to collect the fluorescence. The optical fiber and optical filter were imported into a photomultiplier tube without any extra fixing device. A simplified PDMS detection cell was designed with guide channels through which the optical fibers were easily aligned to the detection window of separation capillary. According to different requirements, laser pointers and different filters were selected by simple switching and replacement. The fluorescence from four different directions was collected at the same detecting point. Thus, the sensitivity was enhanced without peak broadening. The fluorescence detection system was simple, compact, low-cost, and highly sensitive, with its functionality demonstrated by the separation and determination of red dyes and fluorescent whitening agents. The detection limit of rhodamine 6G was 7.7 nM (S/N = 3). The system was further applied to determine illegal food dyes. The CE system is potentially eligible for food safety analysis.
authors.affiliation: College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China.
authors.forename: Haiyun
authors.initials: H
authors.lastname: Zhai
authors.affiliation: College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China.
authors.forename: Kaisong
authors.initials: K
authors.lastname: Yuan
authors.affiliation: College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Yu
authors.affiliation: School of Pharmaceutical Science, Sun Yat-sen University, Guangzhou, P. R. China.
authors.forename: Zuanguang
authors.initials: Z
authors.lastname: Chen
authors.affiliation: College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China.
authors.forename: Zhenping
authors.initials: Z
authors.lastname: Liu
authors.affiliation: College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China.
authors.forename: Zihao
authors.initials: Z
authors.lastname: Su
mesh_terms: D019075:Electrophoresis, Capillary / Q000295:instrumentation*; D004867:Equipment Design; D005456:Fluorescent Dyes; D005504:Food Analysis / Q000295:instrumentation* / Q000379:methods; D057230:Limit of Detection; D055100:Optical Fibers; D013050:Spectrometry, Fluorescence / Q000295:instrumentation*
chemical_list: D005456:Fluorescent Dyes
keywords: Capillary electrophoresis; Fluorescence detection system; Four-branch optical fiber; Y-style optical fiber