Biology subjects

Bardzil, J.

Publications and source records attributed to Bardzil, J..

3 recordsLinked to original sources

bioRxiv2026

Continuous mass photometry by single molecule trapping

The dynamic choreography of biomolecular interactions underpins the processes of life, but its direct observation remains challenging. Here, we introduce confined diffusion mass photometry, enabling hour-long, mass-resolved observation of individual biomolecules, their complexes and interactions with up to sub-kDa mass precision and ms temporal resolution. Our approach represents a quantitative time-resolved single-molecule measurement modality for studying complex biomolecular mechanisms in action.

biophysics↗

bioRxiv2025

Deep learning-based event classification of mass photometry data for optimal mass measurement at the single-molecule level

Mass photometry (MP) is a powerful technique for studying biomolecular structure, interactions, and dynamics in solution. It detects and quantifies small reflectivity changes at a glass-water interface during protein (un)binding, with signals typically averaged over 100 milliseconds. However, particle motion at the point of single-molecule measurement can compromise key metrics such as mass resolution, sensitivity, and concentration. We present a three-dimensional convolutional residual network trained via supervised learning to classify landing events based on their spatiotemporal dynamics. By analysing 3D event thumbnails, our method isolates optimal single-molecule measurements, eliminating cumulative histogram artifacts and improving resolving power by up to a factor of 2. Validated across diverse experimental datasets--including resolved and partially resolved samples, and varying masses, concentrations, and integration times--our approach delivers robust performance under (sub)optimal conditions. Our approach provides measurement-level data-driven feedback, facilitating high quality MP measurements in challenging scenarios.

biophysics↗

bioRxiv2024

Best practice mass photometry: A guide to optimal single molecule mass measurement

Mass photometry (MP) has emerged as a powerful approach to study biomolecular structure, dynamics and interactions. The capabilities of the method ultimately hinge on the ability to accurately measure the tiny optical contrast generated by individual molecules landing at a glass-water interface, which enables mass-resolved quantification of biomolecular mixtures. Ideally, this capability is only limited by shot noise inherent to photon detection, but in practice depends on additional parameters and details of the assay. Here, we focus on the key parameters affecting MP performance, and present simple steps that can be taken to achieve optimal MP performance in terms of mass resolution, quantitative detection limit and analyte concentration range without compromising the ease and simplicity of the technique.

biophysics↗