Multiplexed electrospray deposition for protein microarray with micromachined silicon device

Multiplexed electrospray deposition device capable of delivering picoliter volumes made by silicon micromachining technology has been developed as a deposition tool for making protein microarrays in a noncontact mode. Upon application of potential difference in the range of 7–9kV, biomolecules dissolved in suitable buffer with nonionic surfactant and loaded on the electrospray tips were dispensed on the substrate with microfabricated hydrogel features (1–10μm) in cone-jet mode. Schiff base chemistry followed by reductive amination was utilized for covalent immobilization.