Integrated Microfluidic Devices for Studying Aging and Adhesion of Individual Bacteria

Abstract

Analysis of single cells provides powerful insight into biological processes that are often missed when a population of cells is studied as an ensemble. We are developing microfluidic-based approaches coupled with optical microscopy to track individual bacteria and to improve the temporal and spatial resolution of single-cell measurements. The microfluidic devices automate the steps of cell culture, synchronization, reagent delivery, and analysis. To study cell growth and aging, we integrated nanochannel arrays into the microfluidic devices that physically trap bacteria. The bacteria grow and divide along the nanochannels in one-dimension, and parent cells and their progeny are easily tracked from generation to generation. With these devices, we are able to determine cell growth and division rates, accumulation of cellular damage over time, and inheritance from one generation to the next. For the adhesion studies, swarmer cells are synchronized in our “baby machine” and delivered to adjacent microchannels where we monitor adhesion of individual bacteria to channel surfaces. To better understand how bacteria attach to surfaces, rates of attachment of mutant strains that lack pili and motility are compared to the rate of attachment of wild-type cells.