An economic approach for construction of a multiplexed capillary electrophoresis system

We describe in this report an economic approach to construct a multiplexed capillary electrophoresis (CE) system with optic-fiber UV detection. To demonstrate the feasibility of this approach, a seven-lane CE setup is built. The system has a background noise of ∼10⁻⁵ absorbance unit, a limit of detection of 3-4 μM for uracil at 254 nm, and a linear dynamic range of 2.5 orders of magnitude. The apparatus consists of three major components: a UV light source, a photodiode array (PDA) and optical module assembly, and a computer. Compared to the recently reported 96-lane capillary electrophoresis system with UV-vis absorbance detection, the cost of goods is reduced by more than 10-fold, and the noise level is improved by 2 to 3 folds. Parallel CE separations of a protein mixture have been performed on this apparatus, and reproducible and high resolution separation results have been obtained. Detailed construction and characterization of the system have also been discussed.