Abstract
A novel on-chip environment measurement with functional gel-microtool was developed. Environment measurement gel-microtool was fabricated by connecting the gel-microbeads impregnated with indicators in a microchip. In this artcle, Bromothymol blue (BTB) and Bromocresol green (BCG) were employed as pH indicators. BTB and BCG have the different indicator range. Rhodamine B is temperature sensitive fluorescent dye and is used for temperature measurement. Gel-microbead is made by salting-out of hydrophilic photo-crosslinkable resin and is manipulated by optical tweezers. Moreover, gel-microbead is polymerized by UV illumination and connected to other gel-microbead under an electrolyte solution. The connection of gel-microbeads is performed by contact of gel-microbeads under UV illumination. Environment measurement gel-microtool with an arbitrary shape is fabricated by connection of the gel-microtool impregnated with arbitrary indicator. Multiple environments measurement gel-microtool included with several indicators is realized by assembly of the gel-microbeads impregnated with different indicators. Environment measurement is performed by detecting the color and the fluorescence intensity of each gel-microbead. We succeeded in the on-chip fabrication of the environment measurement gel-microtools such as circular pH measurement gel-microtool and wide range pH measurement gel-microtool in a microchip.
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This research was supported by the Ministry of Education, Culture, Sports, Science and Technology of Japan through Grants-in-Aid for Scientific Research (Nos. 17040017, 19760170, and 17076004).
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Maruyama, H., Fukuda, T. & Arai, F. Functional gel-microbead manipulated by optical tweezers for local environment measurement in microchip. Microfluid Nanofluid 6, 383–390 (2009). https://doi.org/10.1007/s10404-008-0401-6
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DOI: https://doi.org/10.1007/s10404-008-0401-6