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bioRxiv · 10.1101/2025.10.31.685671

A Python framework for magnetic tweezers real-time image processing and microscope control

London, J. A.·Singh, A. K.·Svendsen, T. C.·Tirtom, N. E.·Root, Z. A.·Fishel, R.
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Abstract

Magnetic tweezers are a popular biophysical instrument for manipulating and measuring single molecules. Most groups rely on custom-built setups tailored to specific experiments, making it challenging to implement and share software. Typically, image acquisition and hardware control are automated via LabVIEW, while real-time video processing is implemented in C++/CUDA libraries. Live processing can eliminate the need to store raw video, enabling high throughput, fast acquisition rates, and simplified experimental workflows. However, no open-source general-purpose software framework currently unifies these capabilities for magnetic tweezers experiments. Here, we introduce MagTrack and MagScope open-source Python-based tools designed to fill this gap. MagTrack is an image-processing library that efficiently determines bead positions from magnetic-tweezers videos using CPU or GPU computation. MagScope is a comprehensive software framework offering a graphical user interface, real-time hardware control, data acquisition, and video processing. It is built on a multiprocessing architecture for responsive, high-throughput computation. Together, MagTrack and MagScope offer a fully customizable, end-to-end, open-source Python alternative to proprietary or fragmented systems, enabling laboratories to adapt and extend the framework according to their experimental needs.

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London, J. A., Singh, A. K., Svendsen, T. C., Tirtom, N. E., Root, Z. A., Fishel, R.. 2025-11-03. A Python framework for magnetic tweezers real-time image processing and microscope control. https://doi.org/10.1101/2025.10.31.685671

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