Epifluorescent single-molecule counting with Streptavidin-Phycoerythrin conjugates.

Anal Biochem

Applied Research and Technology, Abbott Diagnostics Division, Abbott Laboratories, Abbott Park, IL, 60064, USA. Electronic address:

Published: December 2022

Single-molecule methods, specifically single-molecule counting, convey high sensitivity in research applications. However, single-molecule counting experiments require specialized equipment or consumables to perform. We demonstrate the utility of using bright Streptavidin-Phycoerythrin (SA-PE) conjugates and an epifluorescence microscope, for single-molecule counting applications. In this work, we show that we can visualize single-molecules on glass surfaces, perform single-molecule diagnostic assays on magnetic microparticles, and image individual foci on cell surfaces. This approach is simple and effective for researchers interested in single-molecule counting.

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http://dx.doi.org/10.1016/j.ab.2022.114955DOI Listing

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