imprint:
Springer Science and Business Media LLC, 2017
Published in:Scientific Reports
Language:
English
DOI:
10.1038/srep42220
ISSN:
2045-2322
Origination:
Footnote:
Description:
<jats:title>Abstract</jats:title><jats:p>The interaction of the anti-adhesive coating, poly(L-lysine)-<jats:italic>graft</jats:italic>-poly(ethylene glycol) (PLL-<jats:italic>g</jats:italic>-PEG) and its Arg-Gly-Asp (RGD) functionalized form, PLL-<jats:italic>g</jats:italic>-PEG-RGD, with the green tea polyphenol, epigallocatechin-gallate (EGCg) was <jats:italic>in situ</jats:italic> monitored. After, the kinetics of cellular adhesion on the EGCg exposed coatings were recorded in real-time. The employed plate-based waveguide biosensor is applicable to monitor small molecule binding and sensitive to sub-nanometer scale changes in cell membrane position and cell mass distribution; while detecting the signals of thousands of adhering cells. The combination of this remarkable sensitivity and throughput opens up new avenues in testing complicated models of cell-surface interactions. The systematic studies revealed that, despite the reported excellent antifouling properties of the coatings, EGCg strongly interacted with them, and affected their cell adhesivity in a concentration dependent manner. Moreover, the differences between the effects of the fresh and oxidized EGCg solutions were first demonstrated. Using a semiempirical quantumchemical method we showed that EGCg binds to the PEG chains of PLL-<jats:italic>g-</jats:italic>PEG-RGD and effectively blocks the RGD sites by hydrogen bonds. The calculations supported the experimental finding that the binding is stronger for the oxidative products. Our work lead to a new model of polyphenol action on cell adhesion ligand accessibility and matrix rigidity.</jats:p>