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bioRxiv · 10.1101/2025.06.27.661720

Estimating anisotropy of single cells using a compliant biaxial stretcher

Marwah, H.·Bhatt, H.·Fartyal, N. S.·Nautiyal, R.·Veer, S.·Pullarkat, P. A.·Balakrishnan, S.
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Abstract

Understanding the mechanical properties of single cells is essential for elucidating their responses to mechanical cues and plays a critical role in development, disease progression, and mechanotransduction. However, probing these properties at the single-cell level remains technically challenging. Traditional methods for probing cellular mechanics are often restricted to a single deformation mode and rely on complex instrumentation, limiting their adaptability. Hence, no single platform currently offers multi-modal cell manipulation, which motivates the development of more versatile tools. Towards this, we are developing an ensemble of compliant micromechanisms that enables diverse modes of cell manipulation on a single chip. Building on our earlier work with a uniaxial stretcher, here we demonstrate estimation of cellular anisotropy using a biaxial stretcher. Since the mechanism transforms motion using deformation, cell stretching forces can be estimated through image-based displacement measurements, without additional sensing modalities, considerably simplifying the device fabrication and operation. By assembling these uniaxial and biaxial stretching micromechanisms on a single chip, we can establish a multi-modal manipulation platform for single cells, which can be augmented with shearing and twisting modes in the future. Such a simple and versatile platform presents a paradigm shift in mechanical testing of single cells.

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Marwah, H., Bhatt, H., Fartyal, N. S., Nautiyal, R., Veer, S., Pullarkat, P. A., Balakrishnan, S.. 2025-07-01. Estimating anisotropy of single cells using a compliant biaxial stretcher. https://doi.org/10.1101/2025.06.27.661720

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