What can we learn by characterizing dynamic heterogeneities during hydrogel degradation?

Herein, we focus on nanogels formed by end-linking of four-arm polyethylene glycol precursors with photolabile groups and characterize dynamical heterogeneities in these systems during degradation. To quantify spatiotemporal fluctuations in the local dynamic behavior, we calculate the self-part of the van-Hove correlation function for the reactive beads for nanogels degrading in various environments. We demonstrate strong deviations from the Gaussian behavior during the degradation and quantify variations in the non-Gaussian parameter as a function of the relative extent of degradation. Further, our study shows that a systematic decrease in solvent quality significantly affects the behavior of the non-Gaussian parameter as a function of the relative extent of degradation. The findings of this study allow one to quantify the dynamic heterogeneities during degradation in various environments and can potentially provide guidelines for designing controllably degrading nanocarriers.