A Tee configuration sheath flow cuvette with square cross-section channels has been produced in PDMS for CE detection. The output of a 1.4 W laser diode operating at 450 nm was focused onto the 300 mu m core of a 370 mu m od fiber optic whose end was inserted into one arm of the Tee for LIF. The optimal configuration had the fiber optic positioned 500 mu m downstream from the intersection and the end of the 35 cm 50 mu m id 365 mu m od capillary just outside the intersection and in the leg of the Tee, resulting in a 90 degrees configuration. Detection limits of 50 and 3 pM and linear calibrations of at least three orders of magnitude were obtained for Lucifer Yellow and fluorescein, respectively.