Microfluidic-based single micro-particle/cell handling techniques
Trap-and-release of a single micro-particle/cell
Microfluidic-based manipulation techniques of single particles such as microbeads, hydrogel particles, and biological cells have been developed because of their potential applications in the fields of biology and chemistry. We developed a simple method for trapping and releasing single particles, such as microbeads and living cells, using dual-function elastomeric valves. Our key technique is the utilization of the elastomeric valve as a dual-function removable trap instead of a fixed trap and a separate component for releasing trapped particles, thereby enabling a simple yet effective trap-and-release of particles. Our simple method can be integrated into microfluidic systems that require single or multiple particle arrays for quantitative and high-throughput assays in applications within the fields of biology and chemistry.
Dynamic single microbead array for multiplex bead-based assay
A simple yet effective dynamic bead-based microarray is necessary for multiplexed high-throughput screening applications in the fields of biology and chemistry. We developed a microfluidic-based dynamic microbead array system using pneumatically driven elastomeric valves integrated with a microchannel in a single polydimethylsiloxane (PDMS) layer that performs the following functions: single microbead arraying with loading and trapping efficiencies of 100%, sequential microbead release for selective retrieval of microbeads of interest, and rapid microarray resettability (< 1 s). A sequential microbead release technique via a multi-step ‘release-retrap-and-repeat’ method was developed for the selective retrieval of trapped microbeads with a simple configuration consisting of a single PDMS layer and a simple macro-to-micro connection. The proposed dynamic microbead array could be a powerful tool for high-throughput multiplex bead-based drug screening or disease diagnosis.