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Identification of membrane antigens and measurement of their expression within a cell population is of fundamental importance to medical and biological studies. In this work, we present a cytometry approach that is based on magnetophoresis and distributed Coulter sensing in a microfluidic system. Our magnetophoretic cytometer offers quantitative analysis of cell membrane antigens on a portable and disposable platform compared to conventional flow cytometers, which are complex, expensive and large systems. Our tests with human breast cancer cells show the utility of our microfluidic device and its potential as a point-of-care instrument for biomedical testing.
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Electronic profiling of membrane antigen expression via immunomagnetic cell manipulation
Membrane antigens control cell function by regulating biochemical interactions and hence are routinely used as diagnostic and prognostic targets in biomedicine. Fluorescent labeling and subsequent optical interrogation of cell membrane antigens, while highly effective, limit expression profiling to centralized facilities that can afford and operate complex instrumentation. Here, we introduce a cytometry technique that computes surface expression of immunomagnetically labeled cells by electrically tracking their trajectory under a magnetic field gradient on a microfluidic chip with a throughput of >500 cells per min. In addition to enabling the creation of a frugal cytometry platform, this immunomagnetic cell manipulation-based measurement approach allows direct expression profiling of target subpopulations from non-purified samples. We applied our technology to measure epithelial cell adhesion molecule expression on human breast cancer cells. Once calibrated, surface expression and size measurements match remarkably well with fluorescence-based measurements from a commercial flow cytometer. Quantitative measurements of biochemical and biophysical cell characteristics with a disposable cytometer have the potential to impact point of care testing of clinical samples particularly in resource limited settings.
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- Award ID(s):
- 1752170
- PAR ID:
- 10098507
- Date Published:
- Journal Name:
- Lab on a Chip
- ISSN:
- 1473-0197
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c9lc00297a
