, Volume 10, Issue 1, pp 55-63
Date: 21 Jul 2007

Microfluidic cell counter/sorter utilizing multiple particle tracing technique and optically switching approach

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


This paper proposes a novel microfluidic system based on a computer controlled digital image processing (DIP) technique and optical tweezers for automatic cell/microparticle recognition, counting and sorting in a continuous flow environment. In the proposed system, the cells/microparticles are focused electrokinetically into a narrow sample stream and are then driven through the region of interest (ROI), where they are recognized and traced in real time using a proprietary DIP system. Synchronized control signals generated by the DIP system are then used to actuate a focused IR laser beam to displace the target cells from the main sample stream into a neighboring sheath flow, which carries them to a downstream collection channel where they are automatically counted. Experimental trials show that the microchip is capable of continuously sorting and counting microparticles with diameters of 5 and 10 μm. In addition, a sample composed of yeast cells and polystyrene (PS) beads is successfully sorted and collected with a 100% of yield ratio and 91.9% of recovery ratio. The proposed system provides a simple, low-cost, high-performance solution for cell manipulation in microfluidic devices.

The preliminary results of the current paper had been presented at the 5th IEEE Conference on Sensors (IEEE Sensors 2006), Daegu, Korea, Oct. 22–25, 2006.