An integrated and simplified microfluidic device using a250
m × 1-4 cm of organic light emitting diode (OLED)array as a two-dimensional light source for single-channeland multichannel whole-column imaging detection wasdeveloped. This f
luorescence detection system was usedfor isoelectric focusing (IEF) of R-phycoerythrin in amicrochip. The IEF conditions were optimized, and thetotal analysis time was extremely reduced to 30 s for2-cm-long microchannels at 700 V/cm of electric fieldstrength without the presence of electroosmotic flow. Thecompression of pH gradient caused by electrolytes drawing into the microchannels was efficiently restrained when1% hydroxylpropylmethyl cellulose in 2% ampholyte wasused as the carrier for IEF. Under optimized IEF conditions, the detection limit of this system was ~0.6
g/mLor 45 pg at 75 nL/column injection of R-phycoerythrin.This OLED-induced f
luorescence detection system forWCID provides a high-speed IEF technique with quantitative ability and the potential for high integration andthroughput microchip systems.