We have recently demonstrated the viability of silicon microarray pins, taking advantage of lithographic and batch processing of silicon micromachining in comparison with conventional and serial processing currently used for commercial pins. The reduced spot size (< 50% in diameter, i.e., > 4X in array density), however, made such undesirable needs as preprinting more pronounced. Preprinting, a common practice in microarray printing, drains out the excess liquid formed outside the liquid channel during dipping. In this paper, we describe how surface wettability can be controlled and report its dramatic effect on the printing performance, for the first time. By making the exterior surfaces hydrophobic and the interior surface hydrophilic, the excess liquid outside the liquid channel is eliminated, and the advantages of silicon-micromachined pins are fully exercised.

This content is only available via PDF.
You do not currently have access to this content.