Enzyme-triggered- and tumor-targeted delivery with tunable, methacrylated poly(ethylene glycols) and hyaluronic acid hybrid nanogels.

Enzyme-responsive polymeric-based nanostructures are potential candidates for serving as key materials in targeted drug delivery carriers. However, the major risk in their prolonged application is fast disassembling of the short-lived polymeric-based structures. Another disadvantage is the limited accessibility of the enzyme to the moieties that are located inside the network. Here, we report on a modified environmentally responsive and enzymatically cleavable nanogel carrier that contains a hybrid network. A properly adjusted volume phase transition (VPT) temperature allowed independent shrinking of a) poly(ethylene glycol) methyl ether methacrylate (OEGMA) with di(ethylene glycol) and b) methyl ether methacrylate (MEO₂MA) part of the network, and the exposition of hyaluronic acid methacrylate (MeHa) network based carboxylic groups for its targeted action with the cellular based receptors. This effect was substantial after raising temperature in typical hyperthermia-based treatment therapies. Additionally, novel tunable NGs gained an opportunity to store- and to efficient-enzyme-triggered release relatively low but highly therapeutic doses of doxorubicin (DOX) and mitoxantrone (MTX). The controlled enzymatic degradation of NGs could be enhanced by introducing more hyaluronidase enzyme (HAdase), that is usually overexpressed in cancer environments. MTT assay results revealed effective cytotoxic activity of the NGs against the human MCF-7 breast cancer cells, the A278 ovarian cancer cells and also cytocompatibility against the MCF-10A and HOF healthy cells. The obtained tunable, hybrid network NGs might be used as a useful platform for programmed delivery of other pharmaceuticals and diagnostics in therapeutic applications.