Static droplet array for culturing single live adherent cells in an isolated chemical microenvironment

Abstract

We present here a new method to easily and reliably generate an array of hundreds of dispersed nanoliter-volume semi-droplets for single-cells culture and analysis. The liquid segmentation step occurs directly in indexed traps by a tweezer-like mechanism and is stabilized by spatial confinement. Unlike common droplet-based techniques, the semi-droplet wets its surrounding trap walls thus supporting the culturing of both adherent and non-adherent cells. To eliminate cross-droplet cell migration and chemical cross-talk each semi-droplet is separated from a nearby trap by an ∼80 pL air plug. The overall setup and injection procedure takes less than 10 minutes, is insensitive to fabrication defects and supports cell recovery for downstream analysis. The method offers a new approach to easily capture, image and culture single cells in a chemically isolated microenvironment as a preliminary step towards high-throughput single-cell assays.

A Review of Advanced Impedance Biosensors with Microfluidic Chips for Single-Cell Analysis

“…However, conventional droplet-based fluidic systems can provide poor environmental survival conditions owing to the fluidic pressure or loss of cell anchoring from the oil coating. Therefore, Hassanzadeh-Barforoushi et al introduced a semi-droplet concept to support the culture of both adherent and non-adherent cells [ 45 ]. By designing an array of hundreds of dispersed nanoliter-volume semi-droplets, spatial confinement of cell-containing liquid in the indexed trap with supporting cell incubation environment enables long-term cell assays.…”

Combinatorial Antimicrobial Susceptibility Testing Enabled by Non-Contact Printing

“…The delivery of the tested compounds to the wells can be a limiting factor of an assay's applicability. The dispensing number of various solutions into numerous wells requires either complex equipment (such as 22 valves for filling 12 wells [30]) or limits the number and dynamic range of the investigated compounds (serial-dilution based gradients of two solutes in 600 wells [37]).…”

Recent Development of Microfluidic Technology for Cell Trapping in Single Cell Analysis: A Review

“…The contact-based approach refers to the cell contacts with the trap region during the capture process. There are some fundamental approaches, including capillary-based trapping in nanoliter microchambers devices [24][25][26][27], sedimentation-based trapping devices [28,29], inertial-based trapping devices [30,31] and microvalve-based devices [32,33]. It does not require external energy; it only relies on the hydrodynamic force.…”