Abstract:A compact light-emitting diode-induced fluorescence detector based on collinear scheme is described. The detector was assembled by all-solid-state optical-electronic components and easily coupled with micro-scale flow analysis system by on-column detection mode. Fluorescein isothiocyanate (FITC) and FITC-labeled amino acids were used as test analytes to evaluate the detector performance by capillary electrophoresis and flow injection analysis techniques. The concentration limit of detection was 10-8 mol·L-1 for FITC-labeled phenylalanine at a signal-to-noise ratio (S/N) of 3 (on-column, 0.05 mm i.d.). The system exhibited a good linear response in the range of 1×10-7-2×10-5 mol·L-1 (r2 =0.999). The relative standard deviation (RSD) of 6 repetitive injections on peak heights is less than 3%.
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