Simple Luminescence Detector for Capillary Electrophoresis

The performance of a homemade, simple, fluorescence-induced capillary electrophoresis (CE) detector is described here. It is based on LED as excitation source, a bifurcated optical fibre as a waveguide and a CCD as a photodetector. The connection of all the components is fairly easy, even for non-experts. This detector provides a low cost and rapid system for the determination of high-quantum-yield native fluorescence compounds and fluorescence derivatised compounds by CE with direct fluorescence deter mination. R-phycoerythrin and B-phycoerythrin were used as models for native fluorescence compounds and amine labelled with FITC were set as models for the fluorescence derivatised ones. Detection limits of 0.50 and 0.64 μg/mL for R-phycoerythrin and B-phycoerythrin and 1.6 � 10−⁷ M for FITC-labelled 1,6-diaminohexane were achieved. The homemade LED-IF detector is not expected to displace the LIF-IF one, but offers another possibility and a cheaper way to solve simple analytical problems for determining biomolecules.