Supramolecular Assembly of Peptide and Metallopeptide Gelators and Their Stimuli‐Responsive Properties in Biomedical Applications

Abstract

Supramolecular gels are a fascinating class of soft materials that have attracted significant attention in recent years. They are composed of small molecule gelators that assemble into supramolecular network structures. The resulting space is filled with solvent. Some gel materials are able to respond to various stimuli making them attractive drug delivery vehicles and as matrices for tissue regeneration. Peptide-based gel materials are particularly attractive as they possess numerous advantages including biocompatibility and biodegradability. Stimuli-responsive peptides that alter properties as a function of pH, redox, temperature, and enzymes offer the potential to create materials with tunable characteristics. In addition, the ability of metal ions to improve the strength of gelation or act as a scaffold has become an interesting approach to develop dynamic peptide gel materials. In this review, the stimuli-responsive properties (pH, redox, temperature, and enzyme responsive properties), as well as the biocompatible/-degradable nature of the peptide gelators are highlighted. In addition, metal ions are discussed as a stimulus to enhance peptide gelation and a number of potential applications of these peptide gelators are provided with an outlook on future directions.

Polyaminoazide mixtures for the synthesis of pH-responsive calixarene nanosponges

“…The ability to provide a response to external stimuli is a highly desirable property for tailored materials designed to accomplish particular functions, such as targeted drug delivery systems, as accounted for by the present burst in literature reports [1–6]. In this context, we have been recently interested in the synthesis of nanosponge materials with tunable properties.…”

Stimuli responsive dynamic transformations in supramolecular gels

“…Chemical analyte responsive gels have huge potential as molecular sensors, aggregation probes, antibacterial agents, conducting materials and water purifying agents. 212,299,[318][319][320][321][322] The presence of chemical analytes can dramatically alter the gel properties. [323][324][325] A specific example is the Tb 3+ metallogel investigated by Ma et al 326 The hydrogel of 2-(2-butyl-1Hbenzimidazol-1-yl)acethydrazide exhibited weak fluorescence at 480 nm which was significantly increased (B4-fold increase) and red shifted to 498 nm in the presence of 0.3 equivalent of terbium nitrate.…”

A Diffusion-Reaction Model for Predicting Enzyme-Mediated Dynamic Hydrogel Stiffening

“…Hydrogels can be prepared through chemical reactions (e.g., chain-growth or step-growth polymerization) or physical interactions (e.g., electrostatic or supramolecular binding) [16,17]. Regardless of the crosslinking method, however, bulk modulus of a hydrogel generally scales with its crosslinking density [14,18].…”