Laser-controlled Injector for Biological Applications

A novel injector for biological applications has been developed. It is a drop-on-demand injector driven by a pulsed laser. Explosive vapor bubbles formed on a thin metal foil, which was irradiated by laser beam, effectively ejected pure water or the biopolymer samples in water solution from a microchannel as small droplets through the port. The size and flight speed of ejected droplets were measured by CCD camera equipped with microscope and synchronized strobe light. The heat efficiency of the injector was evaluated to compare with that of conventional thermal inkjet unit. Furthermore, antigen-antibody reaction using ejected antibody solution was tested. Ejected antibody dots for procollagen type I c-peptide (P1CP) were successfully immobilized on a cyclo olefin copolymer (COC) substrate with a commercially available polymer coating. By using formed antibody dots for a sandwich ELISA the P1CP antigen was effectively detected showing that the injector is applicable for biological application such as micro immunoassay chip.