Fabrication and testing of polydimethylsiloxane (PDMS) microchannel for lab-on-chip (LOC) magnetically-labelled biological cells separation

Abstract

Microfluidics channel of micron-to millimeter in dimension has been widely used for fluid handling in transporting, mixing and separating biological cells in Lab-on-Chip (LoC) applications. In this research, fabrication and testing of Polydimethylsiloxane (PDMS) microfluidic channel for Lab-on-chip magnetically-labelled biological cells separation is presented. The microchannel is designed with one inlet and outlet. A reservoir or chamber is proposed as an extra component of the microchannel design for ease of trapping the intended biological cells in LoC magnetic separator system. The PDMS microchannel of circular-shaped chamber geometry has been successfully fabricated using replica molding technique from SU-8 negative photoresist mold. An agglomerate-free microbeads flowing has been observed using the fabricated PDMS microchannel. Trapping of microbeads in the trapping chamber with 2.0 A current supply in the continuous microfluidics flow > 100 µL/min has also been demonstrated. In conclusion, a separation of biological cells labelled with magnetic microbeads is expected to be realized using the fabricated PDMS microchannel.