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bioRxiv · 10.1101/2021.04.22.441044

Imaging the ultrastructures and dynamics of live erythrocyte membranes at the single-molecule level with a far-red probe on a microfluidic platform

Ye, Z.·Yang, W.·Wang, S.·Zheng, Y.·Zhang, X.·Yu, H.·Luo, C.·Peng, X.·Xiao, Y.
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Abstract

Both the ultrastructures and dynamics of living erythrocyte membranes provide critical criteria for clinical diagnostics. However, it is challenging to simultaneously visualize these features at the single-molecule level due to the rigid photophysical requirements of different single-molecule imaging techniques. Herein, we rationally developed a far-red boron dipyrromethene membrane (BDP-Mem) probe that not only retained consistent and intensive single-molecule emission but also possessed the capability to photoswitch on cellular membranes. We also constructed a microfluidic platform for the noninvasive trapping and long-term imaging of nonadherent erythrocytes. By combining these advantageous technologies, super-resolution reconstruction and single-molecule tracking of living human RBC membranes were achieved at the molecular scale in a high-throughput fashion. Our integrated paradigm defines a quantitative approach for analyzing living RBC membranes under physiological and pathological conditions, improving imaging precisions and revealing new perspectives for future disease diagnostic approaches.

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Ye, Z., Yang, W., Wang, S., Zheng, Y., Zhang, X., Yu, H., Luo, C., Peng, X., Xiao, Y.. 2021-04-23. Imaging the ultrastructures and dynamics of live erythrocyte membranes at the single-molecule level with a far-red probe on a microfluidic platform. https://doi.org/10.1101/2021.04.22.441044

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