A low-cost light-emitting diode induced fluorescence detector for capillary electrophoresis based on an orthogonal optical arrangement

Talanta. 2009 May 15;78(3):1155-8. doi: 10.1016/j.talanta.2009.01.033. Epub 2009 Jan 24.

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.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / isolation & purification
  • Costs and Cost Analysis
  • Electrophoresis, Capillary / instrumentation*
  • Equipment Design
  • Fluorescein-5-isothiocyanate
  • Fluoresceins
  • Fluorescence
  • Fluorescent Dyes
  • Light

Substances

  • Amino Acids
  • Fluoresceins
  • Fluorescent Dyes
  • Fluorescein-5-isothiocyanate