Biocompatible nanogels with tunable size and tailorable properties: A simple synthesis by self-assembly and disulfide crosslinking of amphiphilic hyperbranched peach gum polysaccharide.

Polysaccharide nanogels (NGs) have shown considerable promise in a multitude of fields, owing to their compelling synergistic attributes. Despite this, simple synthesis of polysaccharide NGs that possess uniform and adjustable sizes, tailored properties, and superior biocompatibility remains a significant challenge. Natural peach gum polysaccharide (PGP), renowned for its outstanding biocompatibility and hyperbranched macromolecular structure, stands out as an excellent candidate for NGs preparation, though it has not yet been explored for this purpose. Herein, we present a facile and effective strategy for preparing PGP-based NGs (PGP-NGs) by leveraging the self-assembly and disulfide crosslinking techniques, without using any surfactants. The resultant PGP-NGs exhibit good aqueous dispersibility, enhanced colloidal stability, high biocompatibility and tunable size. Moreover, our strategy enables the direct creation of functional PGP-NGs to accommodate diverse applications by simultaneously modifying PGP with lipoic acid (LA) and other functional molecules, as confirmed by the synthesis of fluorescent PGP-RB-NGs in this study. These PGP-RB-NGs, with their bright fluorescence, efficient cellular internalization and low cytotoxicity, are promising for cell imaging applications. Additionally, the preparation of doxorubicin hydrochloride (DOX)-loaded PGP-NGs can be readily achieved through our strategy. This study thereby provides an effective strategy for constructing robust PGP-based NGs.