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bioRxiv · 10.1101/2024.05.08.593179

SCO-pH: Microfluidic dynamic phenotyping platform for high-throughput screening of single cell acidification

Jeong, H.·Leyes Porello, E. A.·Rosario, J. G.·Kuang, D.·Han, S. H.·Sul, J.-Y.·Lim, B.·Lee, D.·Kim, J.
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Abstract

Studies on the dynamics of single cell phenotyping have been hampered by the lack of quantitative high-throughput metabolism assays. Extracellular acidification, a prominent phenotype, yields significant insights into cellular metabolism, including tumorigenicity. Here, we develop a versatile microfluidic system for single cell optical pH analysis (SCO-pH), which compartmentalizes single cells in 140-pL droplets and immobilizes approximately 40,000 droplets in a two-dimensional array for temporal extracellular pH analysis. SCO-pH distinguishes cells undergoing hyperglycolysis induced by oligomycin A from untreated cells by monitoring their extracellular acidification. To facilitate pH sensing in each droplet, we encapsulate a cell-impermeable pH probe whose fluorescence intensities are quantified. Using this approach, we can differentiate hyperglycolytic cells and concurrently observe single cell heterogeneity in extracellular acidification dynamics. This high-throughput system will be useful in applications that require dynamic phenotyping of single cells with significant heterogeneity.

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Jeong, H., Leyes Porello, E. A., Rosario, J. G., Kuang, D., Han, S. H., Sul, J.-Y., Lim, B., Lee, D., Kim, J.. 2024-05-11. SCO-pH: Microfluidic dynamic phenotyping platform for high-throughput screening of single cell acidification. https://doi.org/10.1101/2024.05.08.593179

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