title: A low-cost light-emitting diode induced fluorescence detector for capillary electrophoresis based on an orthogonal optical arrangement.
abstract: In this work, a simple and low-cost miniaturized light-emitting diode induced fluorescence (LED-IF) detector based on an orthogonal optical arrangement for capillary electrophoresis (CE) was developed, using a blue concave light-emitting diode (LED) as excitation source and a photodiode as photodetector. A lens obtained from a waste DVD-ROM was used to focus the LED light beam into an approximately 80 microm spot. Fluorescence was collected with an ocular obtained from a pen microscope at 45 degrees angle, and passed through a band-pass filter to a photodiode detector. The performance of the LED-IF detector was demonstrated in CE separations using sodium fluorescein and fluorescein isothiocyanate (FITC)-labeled amino acids as model samples. The limit of detection for sodium fluorescein was 0.92 microM with a signal-to-noise ratio (S/N) of 3. The total cost of the LED-IF detector was less than $ 50.
authors.affiliation: Institute of Microanalytical Systems, Zhejiang University, Hangzhou 310058, China.
authors.forename: Feng-Bo
authors.initials: FB
authors.lastname: Yang
authors.forename: Jian-Zhang
authors.initials: JZ
authors.lastname: Pan
authors.forename: Ting
authors.initials: T
authors.lastname: Zhang
authors.forename: Qun
authors.initials: Q
authors.lastname: Fang
mesh_terms: D000596:Amino Acids / Q000302:isolation & purification; D003365:Costs and Cost Analysis; D019075:Electrophoresis, Capillary / Q000295:instrumentation*; D004867:Equipment Design; D016650:Fluorescein-5-isothiocyanate; D005452:Fluoresceins; D005453:Fluorescence; D005456:Fluorescent Dyes; D008027:Light
chemical_list: D000596:Amino Acids; D005452:Fluoresceins; D005456:Fluorescent Dyes; D016650:Fluorescein-5-isothiocyanate