Grafting Vitamin B onto Lignin to Produce Highly Bioactive Materials for Wound Dressing Hydrogels
Yi Yang, Ning Ding, Xinyao Du, Daqian Gao, Débora Puglia, Fengning Wang, Xiao Hui Yang, Fei Xu, Weijun Yang
Abstract
The low radical scavenging activity (RSA) and antibacterial efficiency of lignin limit its applications as a value-added bioactive material. In order to produce greener lignin-based bioactive agents, in this work, vitamin B1 (VB1) was grafted onto lignin nanoparticles (LNPs) through a simple Mannich reaction. The structure and bioactivities of LNP-VB were then studied, and the antimicrobial rates of LNP-30VB against Escherichia coli and Staphylococcus aureus reached 98 and 90%, respectively, increasing by 172 and 291% compared to that of LNPs. Meanwhile, the RSA of LNP-VB was measured by DPPH and HUVEC methods, and the RSA of LNP-30VB was enhanced from 71.9% (LNP) up to 82.4%. Therefore, the RSA and antibacterial activities of LNP-VB were simultaneously and greatly improved, and their mechanisms were also elucidated, which mainly depends on the structure evolution, such as more phenoxyl radicals and H + can be dissociated from lignin phenol hydroxyl, and new forming tertiary amines will also affect the microbial physiological activity. Based on excellent bioactivities, LNP-VB was then utilized for the preparation of wound dressing hydrogels, and faster wound healing and less inflammation effects can be achieved. Meanwhile, the granulation tissue and re-epithelialization phenotype can also be observed at the edge of the wound when analyzed via H&E staining.