Activating PEG host to enable spatially controlled surface functionalization of nanocarriers for biomedical applications.

Abstract

Surface functionalization with biomolecules transforms nanocarriers by integrating a range of bioderived functionalities; however, conventional methods often yield low efficiency and uneven ligand distribution, and compromise the structural integrity of nanocarriers. Here, we introduce a breakthrough approach that activates the traditionally inert PEG corona, enabling precise and spatially controlled functionalization of nanocarriers with biologically relevant entities. Using fluorescence resonance energy transfer (FRET) between pyrene and FITC, we confirm accurate spatial distribution of ligands. Our method achieves exceptional efficiency and stability, maintaining over 40% of functional molecules across three cycles of washing and resuspension under various aqueous conditions. In vitro assays reveal high biological efficacy, with engineered polymersomes supporting targeted cellular interactions. Functionalization with diverse ligands introduces specific biological functionalities, including mitochondrial targeting, cell migration stimulation, and enhanced receptor-mediated endocytosis. This rapid, efficient, and user-friendly strategy for PEG surface functionalization heralds remarkable advances in nanomedicine and biomaterials.