A highly sensitive and small flow-type chemical analysis system with integrated absorptiometric micro-flowcell

A new type of chemical analysis system with a micromachined chemical reaction device is presented as a first step towards achieving micro-total analysis systems(/spl mu/-TAS). Two micro-mixers and a an absorptiometric flowcell were integrated into the one-chip device with dimensions of 24 mm/spl times/10 mm/spl times/2 mm. This device provided high sensitivity and allowed the miniaturization of other elements such as pump, battery, and reagent's bottle. Consequently, the whole size of the analysis system with the micro-device was 203 mm/spl times/86 mm/spl times/76 mm, which was about 1/200 of the size of commercial systems (Hitachi FIA system) at volume ratio. Total consumption of reagents for one test was around 2 /spl mu/L, which was 1/250 smaller than that of the commercial one. The correlation result by using a phosphate standard solution showed good linearity and high sensitivity (0.69 Abs/ppm) which was ten times larger than that of the commercial one. Though micro-machining was applied to a limited part; the mixing/reaction and detection part, it well demonstrated the advantages of /spl mu/-TAS; namely, good portability with good analytical performance.