Refining the Design of Diblock Elastin-Like Polypeptides for Self-Assembly into Nanoparticles

Diblock copolymers based-on elastin-like polypeptide (ELP) have the potential to undergo specific phase transitions when thermally stimulated. This ability is especially suitable to form carriers, micellar structures for instance, for delivering active cargo molecules. Here, we report the design and study of an ELP diblock library based on ELP-[M1V3-i]-[I-j]. First, ELP-[M1V3-i]-[I-j] (i = 20, 40, 60; j = 20, 90) that showed a similar self-assembly propensity (unimer-to-aggregate transition) as their related monoblocks ELP-[M1V3-i] and ELP-[I-j]. By selectively oxidizing methionines of ELP-[M1V3-i] within the different diblocks structures, we have been able to access a thermal phase transition with three distinct regimes (unimers, micelles, aggregates) characteristic of well-defined ELP diblocks.Nanomedicine: an integrative approac

Thermosensitive Hybrid Elastin-like Polypeptide-Based ABC Triblock Hydrogel

We report the synthesis of a well-defined hybrid ABC triblock terpolymer containing a synthetic poly(trimethylene carbonate) (PTMC) block A and a thermosensitive BC diblock of recombinant elastin-like polypeptides (ELPs). The triblock in diluted solution (0.1–0.3% w/v), at low temperatures in ultrapure water, forms micellar structures of 10–60 nm sizes in diameter as characterized by dynamic light scattering (DLS) and liquid atomic force microscopy (AFM). While heated above its transition temperature (Tt), larger particles of 200–300 nm sizes are obtained, consistent with the formation of coacervates. When concentrated, the viscosity of the triblock copolymer solution progressively increases, giving a free-standing gel at 4% w/v formed by a network of micron-sized particles. The formed hydrogels are thermally reversible, and their sol–gel transitions are fast and sharp. The gel formation mechanism appears to interestingly biomimic tropoelastin, the native monomeric form of natural elastin, as demonstrated by optical and cryogenic-scanning electron microscopy (cryo-SEM) imaging

Design and self-assembly of PBLG-b-ELP hybrid diblock copolymers based on synthetic and elastin-like polypeptides

The precision synthesis and self-assembly of amphiphilic copolypeptides containing a recombinant elastin-like polypeptide (ELP) block used as a macroinitiator for the ring opening polymerization (ROP) of γ-benzyl-L-glutamate (γ-BLG NCA) are herein presented. The molecular weight of the resulting PBLG-b-ELP block copolypeptides was precisely controlled without the use of complex initiator or demanding experimental setup. Diblock copolypeptides were obtained with an excellent control of the polymerization highlighted by the dispersity below 1.04. These amphiphilic hybrid synthetic/recombinant copolypeptides were self-assembled in water and the nanoparticles obtained were characterized by a combination of dynamic light scattering and electron microscopy. A variety of morphologies, namely polymersomes, inter-connected worm-like micelles and spherical micelles, were evidenced depending on the hydrophilic ratio of the diblocks as well as the self-assembly procedure.Développement de squelettes polypeptidiques recombinants pour la synthèse de glycoconjugués multivalents parfaitement défini