SmartPin - An Automated Multi-Function Liquid Dispensing System

In this paper, the implementations of micro-line drawing function of the SmartPin is discussed. SmartPin is a self- sensing liquid aspiring/dispensing pin originally intended for DNA/protein microarray applications. For non-contact, computer controlled drawing of microlines and other features, two approaches, the spot-sequence and liquid-column-sweeping are considered and tested. Multi-threading real time control implementation is discussed along with operation specifics. Drawing capability of the SmartPin is experimentally verified by generating 2-mm lines and 1 mm-side squares with 3xSSC salt buffer solution of 0.3% fluorescent Cy-3 dye. Scan results confirm the non-contact, micron-sized drawing capability of the SmartPin.