Microfluidics for long-term single-cell time-lapse microscopy: Advances and applications

Abstract

Cells are inherently dynamic, whether they are responding to environmental conditions or simply at equilibrium, with biomolecules constantly being made and destroyed. Due to their small volumes, the chemical reactions inside cells are stochastic, such that genetically identical cells display heterogeneous behaviors and gene expression profiles. Studying these dynamic processes is challenging, but the development of microfluidic methods enabling the tracking of individual prokaryotic cells with microscopy over long time periods under controlled growth conditions has led to many discoveries. This review focuses on the recent developments of one such microfluidic device nicknamed the mother machine. We overview the original device design, experimental setup, and challenges associated with this platform. We then describe recent methods for analyzing experiments using automated image segmentation and tracking. We further discuss modifications to the experimental setup that allow for time-varying environmental control, replicating batch culture conditions, cell screening based on their dynamic behaviors, and to accommodate a variety of microbial species. Finally, this review highlights the discoveries enabled by this technology in diverse fields, such as cell-size control, genetic mutations, cellular aging, and synthetic biology.

Exploiting fluctuations in gene expression to detect causal interactions between genes

“…We used a microfluidic device commonly called “mother machine” to follow growing and dividing cells for hundreds of generations in controlled environments [50, 51]. Single-cells are trapped in micrometer wide trenches.…”

Integrating microfluidics and synthetic biology: advancements and diverse applications across organisms

“…This microfluidic platform has massively contributed to the recent advances in genetic circuits and understanding bacterial dynamics. 15,38 Zhang et al 15 have reported a genetic circuit resembling closely to the repressilator, with controlled amplitude and period. They use mVenus as the reporter gene regulated by a dual-input promoter and uses salicylate for inducing changes in amplitude and IPTG for period.…”

A Review of Fabrication Techniques and Optimization Strategies for Microbial Biosensors

“…These techniques can be used to create microscale channels and chambers for the microorganism to reside in. These microscale structures can be integrated with a transducer to produce a measurable signal [35]. Some commonly used microfabrication techniques in the fabricating microbial biosensors are:…”