Targeted isolation and analysis of single tumor cells with aptamer-encoded microwell array on microfluidic device

Abstract

Microfluidic-based single cells analysis has been of great interest in recent years, promising disease diagnosis and personalized medicine. Current technologies are challenging in bioselectively isolating specific single cells from complex matrices. Herein, a novel microfluidic platform integrated with cell-recognizable aptamer-encoded microwells was specifically developed to isolate single tumor cells with satisfied single-cell occupancy and unique bioselectivity. In this work, the designed microwell-structures enable us to encourage strong 3D local topographic interactions of the target cell surface with biomolecules and regulate the single-cell resolution. Under the optimized size of microwells, the single-cell occupancy was significantly enhanced from 0.5% to 88.2% through the introduction of the aptamer. Analysis of the target cells was directly performed in short time periods (<5.0 min) with small volumes (4.5 μL). Importantly, such an aptamer-enabled microfluidic device shows an excellent selectivity for target single cells isolation compared with three control cells. Subsequently, targeted isolation and analysis of single tumor cells were demonstrated by using artificial complex cell samples at simulated conditions, and various cellular carboxylesterases were studied by time-course measurements of cellular fluorescence kinetics at individual-cell level. Thus, our technique will open up a new opportunity in single-cell level-based disease diagnosis and personalize medicine screening.

Engineering Cell‐Compatible Paper Chips for Cell Culturing, Drug Screening, and Mass Spectrometric Sensing

“…In the future, this cell-compatible paper chips could be extended for the screening of more complex phenotypic responses. [ 30 ] Briefl y, PDMS prepolymer and curing agent (10:1) were premixed and then poured onto the cell culture dishes as a mold. The PDMS prepolymer was degassed in a vacuum chamber and further cured in a 65 °C oven for 3 h. Furthermore, the top-layered PDMS was peeled from the dishes and the triangularshaped microwells were fabricated with a fresh scalpel blade to match the paper sharp.…”

High-throughput screening approaches and combinatorial development of biomaterials using microfluidics

“…Selective single cells isolation has become available through the combined use of fluidic regimes and biomolecular chemistry technologies [168], or more simply through geometrical displacement and positioning [169]. Delicate handling of cells has now become possible by incorporation of non-invasive techniques such as optical tweezers [170,171] and dielectrophoresis [172,173], or through immunomagnetic probes targeting different cell populations [166,174,175].…”

Living Cell Microarrays: An Overview of Concepts

“…In another study performed by Chen et al [110], an aptamer targeting Ramos cells was used to isolate and analyze single tumor cells with microwell arrays on a microfluidic device. The microwell array was coated with avidin to bind the biotinylated aptamers.…”