Quantitative characterization of cell-to-cell mechanical interactions using holographic optical tweezers

Cell-to-cell mechanical interactions are fundamental to physiological and pathological processes, yet their precise quantification remains technically challenging. In this study, we present a high-precision cellular mechanics measurement platform utilizing holographic optical tweezers (HOT) to dynamically probe mechanical responses during cell binding and separation. This system enables dynamic probing of mechanical responses during cell binding and separation by combining nanometer-scale displacement tracking with optical force field reconstruction, achieving sub-piconewton force sensitivity (0.44±0.17 pN along the x -axis). Additionally, integrated morphological imaging allows for the generation of accurate force–deformation curves, enabling quantitative analysis of cellular viscoelastic properties through standardized stress relaxation and creep compliance assays. This non-invasive and high-fidelity approach provides a powerful tool for characterizing dynamic cell-to-cell mechanical interactions.