In Situ-Forming Polyamidoamine Dendrimer Hydrogels with Tunable Properties Prepared via Aza-Michael Addition Reaction

摘要

In this work, we describe synthesis and characterization of novel in situ-forming polyamidoamine (PAMAM) dendrimer hydrogels (DHs) with tunable properties prepared via highly efficient aza-Michael addition reaction. The nucleophilic amines on the dendrimer surface reacted with α, β-unsaturated ester in acrylate groups of polyethylene glycol diacrylate (PEG DA, MW=575 g/mol) via aza-Michael addition reaction to form dendrimer hydrogels without catalyst. The solidification time, rheological behavior, network structure, swelling and degradation properties of the hydrogel were tuned by adjusting dendrimer surface acetylation degree and dendrimer concentration. The DHs were shown to be highly cytocompatible and support cell adhesion and proliferation. We also prepared an injectable dendrimer hydrogel formulation to deliver anticancer drug 5-FU and demonstrated that the injectable formulation efficiently inhibited tumor growth following intratumoral injection. Taken together, this new class of dendrimer hydrogel prepared by aza-Michael addition reaction can serve as a safe tunable platform for drug delivery and tissue engineering.