Crosslinking Mechanisms of Phenol, Catechol, and Gallol for Synthetic Polyphenols: A Comparative Review

Abstract

Since the first introduction of a synthetic polyphenol called polydopamine, both it and its derivatives have received significant attention from material scientists owing to their unique functionality. In particular, synthetic polyphenols have been utilized as interfacial engineering tools; many important review papers have been published regarding this topic. However, despite those that have focused on the applicability of synthetic polyphenols, fundamental aspects of crosslinking mechanisms and resultant characteristics have still been overlooked in the community. This review covers the mechanisms for building synthetic polyphenols, which are dependent on the number of hydroxyl groups of each phenolic building block. The inherent physicochemical properties of the developed polyphenolic materials are discussed in depth herein. This review can provide guidelines for selecting appropriate phenolic building blocks when designing relevant polyphenolic biomaterials.

Gallic acid: design of a pyrogallol-containing hydrogel and its biomedical applications

“…Pyrogallol can undergo oxidative polymerization under physiological conditions or in the presence of a catalyst. 11,20 UV light can also accelerate oxidative crosslinking. 30 Furthermore, the crosslinking mechanism and products are influenced by the reaction conditions.…”

“…10 In addition to its pharmacological effects, the galloyl group in GA can also interact with other materials (such as proteins, polysaccharides, and synthetic polymers) through covalent and noncovalent interactions. 11 GA exhibits outstanding biological properties and physicochemical features. It can serve as a crosslinking agent and a bioactive additive, either through direct blending with polymers or via the formation of covalent bonds on polymer chains, thereby creating multifunctional hydrogels.…”

Sensing platform for the highly sensitive detection of catechol based on composite coupling with conductive Ni3(HITP)2 and nanosilvers

“…As a main hydroxylation product of phenolic contaminants, catechol can be easily oxidized to generate reactive oxygen species, such as cytotoxic semiquinone radicals and quinones. 1,2 Catechol is extremely miscible with water and easily migrates into the soil and aquatic environments, posing a serious threat to both human health and aquatic organisms, including central nervous system damage, mutations, vascular collapse, DNA breakage and chromosomal aberrations. 3,4 Catechol pollutants exist in various industries, including pharmaceutical production, the chemical industries and agriculture, and it is estimated that 25 000 tons of catechol are discharged into the environment every year.…”

A surface-independent bioglue using photo-crosslinkable benzophenone moiety

“…10,11 In the meantime, other polyphenol materials such as poly(tannic acid), poly(norepinephrine), poly(gallic acid) shows similar potentials as adhesives and applications in optical materials, sensors, and biomedical materials. [12][13][14] Hydrogen cyanide (HCN)-derived polymers such as AMN have been studied for decades in prebiotic chemistry; however, HCNbased coating was only discovered in 2015. 15 AMN-based coatings have several advantages, such as ease-to-produce and biocompatibility, making them a favorable material in biomedical applications.…”

“…10,11 In the meantime, other polyphenol materials such as poly(tannic acid), poly(norepinephrine), poly(gallic acid) shows similar potentials as adhesives and applications in optical materials, sensors, and biomedical materials. 12–14…”