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bioRxiv · 10.1101/060269

A wireless centrifuge force microscope (CFM) enables multiplexed single-molecule experiments in a commercial centrifuge

Tony Hoang·Dhruv S. Patel·Ken Halvorsen
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Abstract

The centrifuge force microscope (CFM) was recently introduced as a platform for massively parallel single-molecule manipulation and analysis. Here we developed a low-cost and selfcontained CFM module that works directly within a commercial centrifuge, greatly improving accessibility and ease of use. Our instrument incorporates research grade video microscopy, a power source, a computer, and wireless transmission capability to simultaneously monitor many individually tethered microspheres. We validated the instrument by performing single-molecule force shearing of short DNA duplexes. For a 7 bp duplex, we collected over 1000 statistics of force dependent shearing kinetics from 2 pN to 12 pN with dissociation times in the range of 10-100 seconds. We extended the measurement to a 10 bp duplex, applying a 12 pN force clamp and directly observing single-molecule dissociation over an 85 minute experiment. Our new CFM module facilitates simple and inexpensive experiments that dramatically improve access to singlemolecule analysis.

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Tony Hoang, Dhruv S. Patel, Ken Halvorsen. 2016-06-22. A wireless centrifuge force microscope (CFM) enables multiplexed single-molecule experiments in a commercial centrifuge. https://doi.org/10.1101/060269

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