Diffusing Colloidal Probes of kT-Scale Biomaterial-Cell Interactions.

In the optimization of applied biomaterials, measurements of their interactions with cell surfaces are important to understand their influence on specific and nonspecific cell surface adhesion, internalization pathways, and toxicity. In this study, a novel approach using dark field video microscopy with combined real-time particle and cell tracking allows the trajectories of biomaterial-coated colloids to be monitored in relation to their distance from cell perimeters. Dynamic and statistical mechanical analyses enable direct measurement of colloid-cell surface association lifetimes and interaction potentials mediated by biomaterials. Our analyses of colloidal transport showed polyethylene glycol (PEG) and bovine serum albumin (BSA) lead to net repulsive interactions with cell surfaces, while dextran and hyaluronic acid (HA) lead to reversible and irreversible association to the cell surface, respectively. Our results demonstrate how diffusing colloidal probes can be used for nonobtrusive, sensitive measurements of biomaterial-cell surface interactions important to therapeutics, diagnostics, and tissue engineering.

Duke Scholars

Author Sharon Gerecht Biomedical Engineering