MEMS-based dispenser array for selective immobilization of molecular recognition elements on bio-image sensor

Selective immobilization of molecular recognition elements on bio-image sensor permits detection of different type of target analytes in a single chip. For the selective immobilization, we designed two types of MEMS-based dispenser array, 2D and 3D dispenser arrays. 2D dispenser embedding microchannels is placed on a senor substrate contacting the sensor elements to introduce biomolecules. Fabrication of a 2D dispenser array requires multi-layer architecture and through holes. PDMS through holes were formed via replication from a two-layer SU-8 mold. We measured transportation of particles through a via-hole. We fabricated top and bottom layer structures of 2D dispenser array. Attachment of a probe array to a microchip enables dispensing multiple droplets containing biomolecules from the probe array. We fabricated probe tips of a 3D dispenser array having 32 × 32 of SiO₂ tapered probes with aperture diameters of 37.2 μm by MEMS fabrication technology.