Intrinsically Disordered Protein-Inspired Nanovector-Based Coacervates for the Direct Cytosolic Transport of Biomacromolecules.

In eukaryotic cells, membraneless organelles (MLOs) are formed via liquid‒liquid phase separation (LLPS) involving intrinsically disordered proteins (IDPs) and biomacromolecules, enabling biomacromolecule transport without vesicles, transporters, or channels. Although MLO-mimetic coacervates generated from synthetic biomaterials can deliver biomacromolecules into cells, they lack the conformational adaptability of IDPs and a defined internalization mechanism, limiting their stability under physiological conditions and hindering biomedical translation. Here, IDP-inspired nanovectors (IDP-NVs) are developed with conformational adaptability capable of forming nanocoacervates (NCs) with biomacromolecules for cytosolic delivery. Mixing with IDP-NVs and cargos results in stable NCs under physiological conditions, and the NCs can directly penetrate cellular membranes through the molecular motion of IDP-NVs. After the internalization, cytoplasmic glutathione triggers NC disassembly, releasing biomacromolecules in the cytosol. The NCs effectively deliver biomacromolecules of diverse sizes, charges, shapes (globular proteins and antibodies), and functions (mRNAs and CRISPR units), demonstrating their versatility and potential for biomedical applications.