Designing a Nitro-Induced Sutured Biomacromolecule to Engineer Electroconductive Adhesive Hydrogels

Abstract

Nitro-functionality, with a large deficit of negative charge, embraces biological importance and has proven its therapeutic essence even in chemotherapy. Functionally, with its strong electron-withdrawing capability, nitro can manipulate the electron density of organic moieties and regulates cellular-biochemical reactions. However, the chemistry of nitro-functionality to introduce physiologically relevant macroscopic properties from the molecular skeleton is unknown. Therefore, herein, a neurotransmitter moiety, dopamine, was chemically modified with a nitro-group to explore its influence on synthesizing a multifunctional biomaterial for therapeutic applications. Chemically, while the nitro-group perturbed the aromatic electron density of nitrocatecholic domain, it facilitated the suturing of nitrocatechol moieties to regain its aromaticity through a radical transfer mechanism, forming a novel macromolecular structure. Incorporation of the sutured-nitrocatecholic strand (S-nCAT) in a gelatin-based hydrogel introduced an electroconductive microenvironment through the delocalization of π-electrons in S-nCAT, while maintaining its catechol-mediated adhesive property for tissue repairing/sealing. Meanwhile, the engineered hydrogel enriched with noncovalent interactions, demonstrated excellent mechano-physical properties to support tissue functions. Cytocompatibility of the bioadhesive was assessed with in vitro and in vivo studies, confirming its potential usage for biomedical applications. In conclusion, this novel chemical approach enabled designing a multifunctional biomaterial by manipulating the electronic properties of small bioactive molecules for various biomedical applications.

A cuttlefish ink nanoparticle-reinforced biopolymer hydrogel with robust adhesive and immunomodulatory features for treating oral ulcers in diabetes

“…Conversely, the PBS and SCE sets remained colorless with hemolysis rates below 5 %, demonstrating favorable hemocompatibility. On the third day of incubation, cells (RAW 264.7, RS1, and HGF) were stained using a calcein-AM/PI live/dead cell staining kit [ 45 , 46 ]. The intensity of green fluorescence in SCE hydrogel groups was nearly on par with the control set, and very few dead cells were detected in these SCE hydrogel groups (as seen in Fig.…”

Polyphenolic Gelatin-Based Bioadhesives

“…(G) Wound closure test on gelatin/S-nCAT hydrogels showing improved bioadhesion compared to commercial sealants. Reproduced with permission from ref . Copyright 2022 American Chemical Society.…”

“…Bioadhesion in these hydrogels was found to be pH-responsive, where increased acidity triggered hydrogel dissociation and aided in controllable deactivation of bioadhesion (Figure D). In another study, bioadhesive electroconductive sutured-nitrocatecholic strands (S-nCAT) were developed, which could be incorporated into gelatin solutions for injectable bioadhesion (Figure E,F) . The results of wound closure tests suggested significant improvements in adhesion strength, reaching ∼40 kPa compared to <5 kPa commercial sealants (Figure G).…”

“…In another study, bioadhesive electroconductive sutured-nitrocatecholic strands (S-nCAT) were developed, which could be incorporated into gelatin solutions for injectable bioadhesion (Figure 2E,F). 35 The results of wound closure tests suggested significant improvements in adhesion strength, reaching ∼40 kPa compared to <5 kPa commercial sealants (Figure 2G). Oxidatively polymerized gallic acid physically complexed with GelMA was copolymerized with poly(ethylene glycol diacrylate) (PEGDA) hydrogels.…”

Designing a Naturally Inspired Conductive Copolymer to Engineer Wearable Bioadhesives for Sensing Applications

“…Combinations of these physical and chemical interactions have been previously demonstrated to play a significant role in enhancing the stability and mechanical properties of the resulting gelatin-based hydrogels. 42,43 We first optimized the final polymer concentration by engineering Gel-MD hydrogels using 50/50 ratio of gelatin/ MD copolymer at final polymer concentrations of 20, 30, and 40% (w/v), denoted as Gel-MD20, Gel-MD30 and Gel-MD40, respectively. Additionally, we synthesized hydrogels with varying ratios of gelatin to MD copolymer (75/25, 50/50, and 25/75) at a final polymer concentration of 30% (w/v) to investigate the impact of the copolymer concentration on the physical properties of the hydrogels.…”