Light-emitting-diode-induced chemiluminescence detection for capillary electrophoresis

In this work, an LED-induced-chemiluminescence (LED-CL) system was developed to extend the application of CL detection in CE. In the LED-CL, the analyte photooxidizes luminol under the irradiation of LEDs and generates CL. Taking the advantage of the small size nature of LEDs, the constructed photoreactor is greatly miniaturized, and especially suitable as a CE detector. The feasibility of the proposed detector was evaluated by detection of riboflavin (RF), flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) after CE separation. Under the optimized conditions, the LODs for RF, FMN and FAD were 0.007, 0.02 and 0.1 microg/mL, respectively, better than those by UV detection. The RSDs were 3.4, 3.6 and 4.1% for 0.5 microg/mL RF, 2 microg/mL FMN and 5 microg/mL FAD, respectively. The LED-CL detector features low cost, miniaturization, fast response, high sensitivity and good reproducibility.