Micropillar arrays enabling single microbial cell encapsulation in hydrogels

Abstract

Single microbial cell encapsulation in hydrogels is an important task to find valuable biological resources for human welfare. The conventional microfluidic designs are mainly targeted only for highly dispersed spherical bioparticles. Advanced structures should be taken into consideration for handling such aggregated and non-spherical microorganisms. Here, to address the challenge, we propose a new type of cylindrical-shaped micropillar array in a microfluidic device for enhancing the dispersion of cell clusters and the isolation of individual cells into individual micro-hydrogels for potential practical applications. The incorporated micropillars act as a sieve for the breaking of Escherichia coli (E. coli) clusters into single cells in a polymer mixture. Furthermore, the combination of hydrodynamic forces and a flow-focusing technique will improve the probability of encapsulation of a single cell into each hydrogel with a broad range of cell concentrations. This proposed strategy and device would be a useful platform for genetically modified microorganisms for practical applications.

Generation and manipulation of hydrogel microcapsules by droplet-based microfluidics for mammalian cell culture

“…Then we discuss two on-chip manipulation strategies (Section 3) for cell-laden microcapsules, sorting and extraction from oil into aqueous phase. We have omitted other strategies of droplet-based microfluidics, such as fission 53 , fusion 54 , disruption 55 , trapping 56 , and storage 57, 58 , as they are still not widely applied in the context of 3D in vitro culture. We then introduce and discuss applications of cell-laden hydrogel microcapsules as 3D culture platforms (Section 4) to study cell growth and proliferation, stem cell differentiation, tissue development, and cell co-culture.…”

High‐Throughput, Miniaturized Clonogenic Analysis of a Limiting Dilution Assay on a Micropillar/Microwell Chip with Brain Tumor Cells

“…Micropillar and Microwell Chip Manufacturing : Previous methods for the fabrication of micropillar chips such as silicon etching and polymer molding were used for production at the prototype level. However, they are not suitable for mass production.…”

Enabling method to design versatile biomaterial systems from colloidal building blocks

“…In the field of tissue engineering, encapsulation of living cells in soft polymers is an opportunistic route that has been explored for regeneration and rehabilitation of functional tissues; this technical approach enables cells to be physically separated from surrounding tissues, providing protection from unwanted attack by the host immune system, while maintaining transport of critical gas, nutrients, wastes, and therapeutic molecules. 54 Currently scientists have developed microsystems able to encapsulate cells in beads, 55 sheets, 56 fibers, 57 and more advanced structures, 58,59 with fine control over size and cell density. Microgels have already been used in this area, particularly for development of injectable hydrogel scaffolds.…”