A Single-Layer PDMS Chamber for On-Chip Bacteria Culture

Abstract

On-chip cell culture devices have been actively developed for both mammalian cells and bacteria. Most designs are based on PDMS multi-layer microfluidic valves, which require complicated fabrication and operation. In this work, single-layer PDMS microfluidic valves are introduced in the design of an on-chip culture chamber for E. coli bacteria. To enable the constant flow of culturing medium, we have developed a (semi-)always-closed single-layer microfluidic valve. As a result, the growth chamber can culture bacteria over long duration. The device is applied for the whole-cell detection of heavy metal ions with genetically modified E. coli. The platform is tested with culturing period of 3 h. It is found to achieve a limit-of-detection (LoD) of 44.8 ppb for Cadmium ions.

An automated microfluidic system for efficient capture of rare cells and rapid flow-free stimulation

“…27,33,41 The capillary network and chamber geometry enable rapid diffusion-based material exchange between flow chambers and culture chambers within 2-3 min without the use of 3D microwells, 35 extensive channel infrastructure, or complex fabrication steps. 28 these designs have no capacity to trap rare cell populations, 24,41,44 or to automate media switching for multiple conditions. 27,43 They also often suffer from long lasting cytokine gradients in their culture chambers.…”

Microfluidics applications for high-throughput single cell sequencing

“…Microfluidic large scale integration (mLSI) enables the fabrication of microfluidic chips containing hundreds to thousands of pneumatic membrane valves that are similar to fluidic multiplexers array [ 80 ]. Valves-based microfluidic devices are designed by two separately cured polydimethylsiloxane (PDMS) layers with channels so that the pneumatic membrane valves are formed when the channels in the two layers are orthogonal to each other [ 81 ]. The flexibility of PDMS allows integration of membrane valves on complex microfluidic chips to create an intricate network of microchannels [ 82 ].…”

Optimization and Fabrication of Multi-Level Microchannels for Long-Term Imaging of Bacterial Growth and Expansion

“…Some of these effects can be quantitatively studied by means of microfluidic devices. Indeed, advances in microfabrication have enabled creation of microdevices with confined geometry and controlled microenvironments to study microbial dynamics at single-cell resolution, see, e.g., [8][9][10][11][12][13][14][15]. These devices can also be used to mimic microstructures, such as those found in soil, using controlled flow and microenvironmental conditions [16].…”