Fabrication of uniform lignin nanoparticles with tunable size for potential wound healing application

The construction of lignin nanoparticles (LNPs) with both lignin properties and nanomaterial properties through controlling the morphologies and structures of lignin is one of the effective ways to realize its application in the field of biomedicine. Firstly, the morphology and chemical structure of LNPs were studied in detailed. The results showed that the chemical structural characteristics of LNPs had not changed significantly and its morphology was more regular shape and narrower size distribution (50-350 nm). Besides, LNPs also exhibited excellent water dispersion stability and high negative zeta potential. Subsequently, LNPs as wound dressings had good antioxidant property, excellent adsorption capacity of protein, outstanding bactericidal activity and remarkable biocompatibility, suggesting that LNPs did not interfere with cell proliferation during wound healing. Finally, the in vivo results of mouse wounds further illustrated that treatment of wounded skin wounds with LNPs enhanced its effective healing. After 15 days, as compared with the untreated control and original lignin (OL) groups, the wounds treated of LNPs was completely closed and granulation tissue formation was advanced. Overall, this study can be a good method for high-value applications of LNPs, and highlighting the advantages of using lignin as medical adjuvant nanomaterials to accelerate wound healing.