Controlling molecular interactions between bioinspired molecules can enable the development of new materials with higher complexity and innovative properties. Here we report on a dynamic system that emerges from the conformational modification of an elastin-like protein by peptide amphiphiles and with the capacity to access, and be maintained in, non-equilibrium for substantial periods of time. The system enables the formation of a robust membrane that displays controlled assembly and disassembly capabilities, adhesion and sealing to surfaces, self-healing and the capability to undergo morphogenesis into tubular structures with high spatiotemporal control. We use advanced microscopy along with turbidity and spectroscopic measurements to investigate the mechanism of assembly and its relation to the distinctive membrane architecture and the resulting dynamic properties. Using cell-culture experiments with endothelial and adipose-derived stem cells, we demonstrate the potential of this system to generate complex bioactive scaffolds for applications such as tissue engineering.
The use of recombinant elastin-like materials, or elastin-like recombinamers (ELRs), in drug-delivery applications is reviewed in this work. Although ELRs were initially used in similar ways to other, more conventional kinds of polymeric carriers, their unique properties soon gave rise to systems of unparalleled functionality and efficiency, with the stimuli responsiveness of ELRs and their ability to self-assemble readily allowing the creation of advanced systems. However, their recombinant nature is likely the most important factor that has driven the current breakthrough properties of ELR-based delivery systems. Recombinant technology allows an unprecedented degree of complexity in macromolecular design and synthesis. In addition, recombinant materials easily incorporate any functional domain present in natural proteins. Therefore, ELR-based delivery systems can exhibit complex interactions with both their drug load and the tissues and cells towards which this load is directed. Selected examples, ranging from highly functional nanocarriers to macrodepots, will be presented.
Biotechnology offers powerful solutions to the challenges that arise during the design and development of new complex biomimetic materials to achieve specific biological responses. Recombinant DNA technologies, in particular, provide unique solutions in the biomaterials field, especially regarding the control of macromolecular architectures involving protein sequences with the aim of addressing the multiple functional requirements needed for biomaterials' applications. Here, elastin-like recombinamers are presented as an example of an extraordinary convergence of different properties that is not found in any other polymer system. These materials are highly biocompatible, stimuli-responsive, show unusual self-assembly properties and can include bioactive domains along the polypeptide chain. Applications of these engineered biomimetic polymers in nanotechnological systems, stimuli-responsive biosurfaces and tissue engineering will be discussed