Versatile programmable eight-path-electrode power supply for automatic manipulating microfluids of a microfluidic chip

A versatile programmable eight-path-electrode power supply (PEPS) system for manipulating microfluids of a complex microfluidic chip has been developed. The PEPS system consisted of a single chip microprocessor as a central control unit and a personal computer (PC) as an upper computer, and the program could be operated under Windows98/2000/XP. The voltage output of each electrode was in the range of 0 to +8000 V (0.1% precision) while the current output was in the range of 0 to +999 μA. The voltage of eight electrodes could be operated either independently or synchronously by random combination of any electrodes through switching. The voltage output modes were “switch-off/floating”, “switch-on” and “grounded” and fast switched at ms-level between these modes, and run time (0.1 s precision) of these modes could be controlled as desired. The PEPS system was conveniently for controlling flow rate and direction of electroosmotic flow (EOF) in a chip network. Six electrodes were chosen to control the repeated ‘injection and separation’ of 1.0 × 10−5 M fluorescein isothiocyanate (FITC) in a six-reservoir glass-based chip. The relative standard deviation (R.S.D., n = 4, S/N = 10) of the repeated operation was 0.9% for the reservation time (tR) and 2.3% for the peak height, respectively.