Fig. 1
From: Chemotactic behaviour of Escherichia coli at high cell density
Microfluidic device used for chemotaxis assays. a Schematic representation of the device, where two reservoirs with different chemical composition are connected by a channel in which the chemoattractant gradient forms. b Central part of the device, highlighted orange in (a), with gradient profile across the channel quantified using fluorescein. Scale bar is 500 \(\mu\)m. The red box indicates the location at which cellular behaviour is recorded. c Examples of gradients, measured in the \(h=50\ \mu\)m device, for cell suspensions of indicated cell densities. Error bars represent measurement error.
