Peptide-based polymers

To be successful in these applications, it is important that materials can self-assemble into precisely defined structures. Peptide-based polymers have many advantages over conventional synthetic polymers since they are able to hierarchically assemble into stable, ordered conformations [4]. Depending on the substituents of the amino acid side chain, polypeptides are able to adopt a multitude of... 

R. J. Pieters, D. T. S. Rijkers, and R. M. J. Liskamp, Application of the 1,3-dipolar cycloaddition reaction in chemical biology Approaches toward multivalent carbohydrates and peptides and peptide-based polymers, QSAR Comb. Sci., 26 (2007) 1181-1190. 

Urry, D. W. (1998). Five axioms for the functional design of peptide-based polymers as molecular machines and materials Principles for macromolecular assemblies. Peptide Sri. 47, 167-178. 

Peptide-based polymers 62, containing imidazole, carboxyl, and hydroxymethyl functionalities, have been prepared from optically active 50d and tested as mimics of enzymes, such as chymotrypsin, which have the same functionalities (Scheme 41) [70]. These polymers exhibit markedly higher activities than the corresponding low molecular weight compounds in the hydrolysis of nitrophenyl and dinitrophenyl esters. Increased activities were... 

Synthetic peptide-based polymers are not new materials homopolymers of polypeptides have been available for many decades and have only seen hmited use as structural materials [5,6]. However, new methods in chemical synthesis have made possible the preparation of increasingly complex polypeptide sequences of controlled molecular weight that display properties far superior to ill-defined homopolypeptides [7]. Furthermore, hybrid copolymers, that combine polypeptide and conventional synthetic polymers, have been prepared and combine the functionality and structure of peptides with the processabihty and economy of polymers [8,9]. These polymers are well suited for applications where polymer assembly and functional domains need to be at length scales ranging from nanometers to microns. These block copolymers are homogeneous on a macroscopic scale, but dissimilarity between the block segments typically results in microphase heterogeneity yield-... 

Interestingly, this mechanical performance is accompanied by an extraordinary biocompatibiUty, although, however, the most striking properties are perhaps their acute smart and self-assembhng nature. These properties are based on a molecular transition of the polymer chain in the presence of water when their temperature is increased above a certain level. This transition, called the inverse temperature transition (ITT), has become the key issue in the development of new peptide-based polymers as molecular machines and materials. The understanding of the macroscopic properties of these materials in terms of the molecular processes taking place around the ITT has established a basis for their functional and rational design [102]. 

D. W. Urry, Five Axioms for the Functional Design of Peptide-Based Polymers as Molecular Machines and Materials Principle for Macromolecular Assemblies. Biopolymers (Peptide Science), 411,167-178 (1998). 

Bertin A, Hermes F, Schlaad H (2010) Biohybrid and peptide-based polymer vesicles. Adv Polym Sci 224 167-195... 

The responsive behavior of ELRs has been defined as their ability to respond to external stimuli. This property is based on a molecular transition of the polymer chain in the presence of water at a temperature above a certain level, known as the Inverse Temperature Transition (ITT). This transition, whieh shares most of the properties of the lower critical solution temperature (LCST), although it also differs in some respects, particularly as regards the ordered state of the folded state, is clearly relevant for the application of new peptide-based polymers as molecular devices and biomaterials. Below a specific transition temperature (T,), the free polymer chains remain as disordered, random coils [20] that are fully hydrated in aqueous solution, mainly by hydrophobic hydration. This hydration is characterized by ordered, clathrate-like water structures somewhat similar to those described for crystalline gas hydrates [21, 22], although somewhat more heterogeneous and of varying perfection and stability [23], surrounding the apolar... 

Another interesting example was the synthesis of peptide-based polymers via the Cu(I)-catalyzed N-C polymerization of azido-phenylalanyl-alanyl-propargyl amide [29] (see Scheme 1.4). 

Synthesis of peptide-based polymers by microwave-assisted cycloaddition by backbone polymerization. Biomacromolecules, 8, 327. 

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