Bioinspired nanotubes from self-assembly of a linear L,D-oligopeptide-poly(ethylene glycol) conjugate

The preparation and structural organization of a new bioinspired nanomaterial are investigated. A hybrid conjugate is obtained by end-linking a linear octapeptide with regular alternating enantiomeric sequence to poly(ethylene glycol). This conjugate is able to self-assemble, forming well-defined nanorods having core/shell morphology with an internal peptide single channel that has, for the first time, been clearly visualized by transmission electron microscopy (TEM) images. It is remarkable that well-defined cylindrical nanoparticles can be formed starting from a linear oligopeptide, the synthesis of which is significantly easier than that of the homologous cycles. In addition, the synthetic strategy and the structure of the conjugate ensure a controlled and regular pegylation of the aggregates and high density PEG blocks in the corona, making the nanoparticles more resistant to phagocytosis and able to prevent biofouling. Such features, along with biocompatibility and stability, make these nanoparticles promising candidates for drug delivery.