Proof of concept for microfluidic spectral flow cytometry

Results are presented from an experimental proof of concept for a full-spectrum microfluidic flow cytometer. Existing flow cytometers operate on photomultiplier tubes (PMTs) and are restricted in the number of available fluorophores, with newer systems costing $250k-$500k. Current EMCCD technology paired with microfluidics promises to offer superior channel decomposition while allowing a significant reduction in price. A device was constructed from polydimethysiloxane (PDMS) with fiber optics for sample excitation and fluorescence collection, and with an 80 micron channel for sample flow. In the first experiment, we captured spectra of individual fluorescently labeled polystyrene beads and demonstrated classification of beads according to their labeling fluorophore, as well as characterization of anomalous beads. In the second experiment, two stoichiometric mixtures of six dyes were created with the successful decomposition of the mixtures into components, using reference spectra acquired on the system. We anticipate the capability of full spectra to enable the extension to twenty-one fluorophores with the microfluidic design creating a robust system with a total cost of under $50,000.