Cell characterization using a protein-functionalized pore

Abstract

We demonstrate a highly-sensitive and label-free method for characterizing cells based on cell-surface receptors. The method involves measuring a current pulse generated when an individual cell passes through an artificial pore. When the pore is functionalized with proteins, specific interactions between a cell-surface marker and the functionalized proteins retard the cell, thus leading to an increased pulse duration that indicates the presence of that specific biomarker. For proof-of-principle, we successfully screened murine erythroleukemia cells based on their CD34 surface marker in both a single and mixed population of cells. Further, we developed a unified constrained statistical model for estimating the ratios of cells in a mixed population. Finally, we demonstrated our ability to screen a small number of cells (hundreds or less) with high accuracy and sensitivity. Overall, our pore-based method is broadly applicable and, in the future, could provide a full range of in vitro cell-based assays.

Biopolymer System for Cell Recovery from Microfluidic Cell Capture Devices

“…[1,2] These technologies focus on coating a surface with a capture moeity and then utilize microfluidic architectures to precisely control and maximize cell–ligand interactions. [3,4,5] The label-free nature of these techniques enables the isolation of cell populations from complex solutions (i.e., whole blood) with minimal or no pre-processing. This allows for the rapid isolation of a wide variety of clinically relevant cell types, ranging from exceedingly rare circulating tumor cells, [5] to CD4+ T cells, [6] to more prevalent neutrophils.…”

Sorting single satellite cells from individual myofibers reveals heterogeneity in cell-surface markers and myogenic capacity

“…A non-pulsatile pressure 19 is used to drive single satellite cells through filters, an inner reservoir, and finally through the functionalized microchannel for measurement. As individual satellite cells transit the microchannel, the flow of current is partially blocked, leading to a transient increase, or pulse, in the electrical resistance (Figure 1C) that is subsequently recorded and analyzed to characterize the cell 20–26 .…”

“…Pulse 3 corresponds to the rare occasion when two cells simultaneously transit the microchannel. As shown, the pulse has a characteristic profile that is easily recognized and discarded 19 . Because we flow cells at a high rate through the channel (~10 6 s −1 shear rate), they only transiently interact with the functionalized antibody.…”

An Overview of Recent Strategies in Pathogen Sensing

“…Carbonaro et al have developed an on-chip artificial pore that could be used to detect bacterial pathogens [20]. The microfluidic chip was constructed with polydimethylsiloxane (PDMS) having a fluid channel (a pore) with cross-sectional dimension of 15 × 15 μm.…”