A remarkable progress of the micro-total analysis system (;TAS) technology has produced many promising devices and applications. Although previous systems have been designed for a specific purpose, it will be more time-saving if they can be used for general purposes and are operated by programming as seen in electronic microprocessors. In this study, we have fabricated a microfluidic device by taking advantage of the excellent features of liquid plugs to realize a liquid-handling device for general purposes.

　The prototype device was shown in Fig1.A. Liquid plugs introduced into the main flow channel could be processed by following the procedure shown in Fig. 1B. We could form plugs of various lengths, exchange the order of the plugs(Fig.2), and merge two plugs for mixing. To show the applicability to bio / chemical analyses, reactions relating to L-glutamate detection were used.

Fig. 1 (A) Structure of the device. (B) Basic procedure.

Fig. 2 Sorting of liquid plugs