Curcumin loaded nanocarriers obtained by self-assembly of a linear D,L-octapeptide-poly(ethylene glycol) conjugate

The preparation and characterization of a novel linear D,L-octapeptide-poly(ethylene glycol) conjugate, for- mulated as biocompatible nanocarrier of hydrophobic drugs, was reported. The PEGylated D,L-octapeptide was designed to self-assemble in core-shell nanoparticles with rod-like morphology obtained by exploiting the self- assembling properties of linear peptides with regularly alternating enantiomeric sequences in tubular structures. The conformational properties of the conjugate and its self-assembling capability were assessed through dynamic light scattering, energy filtered-transmission electron microscopy, scanning electron microscopy, circular di- chroism, fluorescence, and proton nuclear magnetic resonance spectroscopy. Furthermore, the upload in pep- tide-polymer nanoparticles of curcumin, adopted as model of hydrophobic drugs, was performed. In fact, despite accumulating evidence suggests that curcumin has different therapeutic activities, its use in medicine is limited to the very low water solubility, low bioavailability and chemical instability. This work addresses such draw- backs showing that nanoparticles obtained by For-(D-Phe-L-Cys(Acm))4-NH-(CH2-CH2-O)45-CH3 self-assembly are effective carriers for curcumin with high drug loading and sustained drug release.