n Situ formation of gold nanoparticles into supramolecular hydrogels by polyphenol chemistry. Properties and applications

Edimburgo

Conferencia; Materials Science Engineering Forum; 2021

Phenol-based supramolecular hydrogels have recently attracted much attention as materials for a wide range of applications. Although significant advances have been made in this field, obtaining new versatile materials that combine synthesis simplicity and suitable functional properties remains a continuous challenge. On the other hand, plasmonic nanoparticles have been widely investigated in the past decades as their unique properties, such as the surface plasmon resonance, provide potential applications as sensors, catalysts, drug delivery, and photothermal therapy amongothers. In this work, the in-situ formation of gold nanoparticles (AuNPs) into supramolecular hydrogels based on polyvinyl alcohol (PVA) and gallic acid (GA), a natural polyphenol, was explored. We investigated both the hydrogen bonding ability and reducing properties of GA to obtain functional hybrid supramolecular nanocomposites hydrogels (PVA-GA-AuNPs). Nucleation and growth of AuNPs, using HAuCl4 as the precursor, occurred in the forming solution of PVA-GA hydrogel, allowing steric stabilization and strict control over the AuNPs size distribution. The sizeand concentration of the AuNPs were optimized, giving spherical 20-30 nm nanoparticles inside the gel network. These hybrid soft materials show promising properties to be applied in different fields encompassing surface-enhanced Raman spectroscopy (SERS) sensors, wound healing, 3D printing, tissue engineering, and so for.