Research

Non-destructive on-chip cell sorting system with real-time microscopic image processing

Kazunori Takahashi¹ , Akihiro Hattori^1,2 , Ikurou Suzuki¹ , Takanori Ichiki^3,4 and Kenji Yasuda¹

¹  Department of Life Sciences, Graduate school of Arts and Sciences, University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo 153-8902 JAPAN

²  Systems Products Division, Sigma Koki, Co. Ltd., 17-2 Shimo-takahagi-shinden, Kawagoe, Saitama 350-1297 JAPAN

³  Department of Electrical & Electronics Engineering, Faculty of Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585 JAPAN

⁴  General Research Center, Graduate School of Engineering, University of Tokyo, 2-11-16 Yayoi, Bunkyo, Tokyo 113-8656 JAPAN

author email corresponding author email

Journal of Nanobiotechnology 2004, 2:5doi:10.1186/1477-3155-2-5

Published:	3 June 2004

Abstract

Studying cell functions for cellomics studies often requires the use of purified individual cells from mixtures of various kinds of cells. We have developed a new non-destructive on-chip cell sorting system for single cell based cultivation, by exploiting the advantage of microfluidics and electrostatic force. The system consists of the following two parts: a cell sorting chip made of poly-dimethylsiloxane (PDMS) on a 0.2-mm-thick glass slide, and an image analysis system with a phase-contrast/fluorescence microscope. The unique features of our system include (i) identification of a target from sample cells is achieved by comparison of the 0.2-μm-resolution phase-contrast and fluorescence images of cells in the microchannel every 1/30 s; (ii) non-destructive sorting of target cells in a laminar flow by application of electrostatic repulsion force for removing unrequited cells from the one laminar flow to the other; (iii) the use of agar gel for electrodes in order to minimize the effect on cells by electrochemical reactions of electrodes, and (iv) pre-filter, which was fabricated within the channel for removal of dust contained in a sample solution from tissue extracts. The sorting chip is capable of continuous operation and we have purified more than ten thousand cells for cultivation without damaging them. Our design has proved to be very efficient and suitable for the routine use in cell purification experiments.