Miniaturization of multifunctional biosensor with enzyme-immobilized beads

We propose a novel method for individual immobilization. Biomaterials were first immobilized on certain support material of which size is almost the same as the size of sensor element. The immobilization enlarges the size of biomaterials to the size of sensor element. Then the support is arranged on the sensor element by self-assembling. The element was microfabricated to have a microstructure for self-assembling, When both size of biomaterial and the element are the same, self-assemble is expected to give one-to-one correspondence, and then individual response. Mixed glass beads immobilized each of various enzyme were put near the pits fabricated one chip and the chip was slanted to roll the beads into the pits. When the beads immobilized only with peroxidase were arranged, the addition of luminol and hydrogen peroxide gave chemiluminescence at almost every site. Next, the beads immobilized only with glucose oxidase as dummy enzyme were mixed with HRP-beads and arranged to the sites. Addition of substrate gave limited number of luminescence-giving sites, though every site had an enzyme-immobilized bead. These results show that two kinds of enzymes were separately arranged in the site in one-to-one correspondence.