Polysucrose hydrogel and nanofiber scaffolds for skin tissue regeneration: Architecture and cell response

Lignin-cellulose complexes derived from agricultural wastes for combined antibacterial and tissue engineering scaffolds for cutaneous leishmaniasis wounds

Bacterial infections in wounds significantly impair the healing process. The use of natural antibacterial products over synthetic antibiotics has emerged as a new trend to address antimicrobial resistance. An ideal tissue engineering scaffold to treat infected wounds should possess antibacterial properties, while simultaneously promoting tissue regrowth. Synthesis of hydrogel scaffolds with antibacterial properties using hemp shive (HT1/HT2) lignin, sugarcane bagasse (SCB) lignin and cellulose was carried out. All lignin samples had low molecular weights and were constituted of G-type β-5 dimers, linked by β-O-4 bonds, as determined by MALDI-TOF-MS. Hemp lignin was more cytotoxic to mouse fibroblasts (L929) compared to SCB lignin. All lignin samples demonstrated antibacterial properties against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis, with greater efficiency against Gram-negative strains. 3D hydrogels were engineered by crosslinking SCB lignin with SCB cellulose in varying weight ratios in the presence of epichlorohydrin. The stiffness of the hydrogels could be tailored by varying the lignin concentration. All hydrogels were biocompatible; however, better fibroblast adhesion was observed on the blended hydrogels compared to the 100% cellulose hydrogel, with the cellulose : lignin 70 : 30 hydrogel showing the highest L929 proliferation and best antibacterial properties with a 24-hour bacterial growth reduction ranging from 30.8 to 57.3%.

Recent Advances in Macroporous Hydrogels for Cell Behavior and Tissue Engineering

Hydrogels have been extensively used as scaffolds in tissue engineering for cell adhesion, proliferation, migration, and differentiation because of their high-water content and biocompatibility similarity to the extracellular matrix. However, submicron or nanosized pore networks within hydrogels severely limit cell survival and tissue regeneration. In recent years, the application of macroporous hydrogels in tissue engineering has received considerable attention. The macroporous structure not only facilitates nutrient transportation and metabolite discharge but also provides more space for cell behavior and tissue formation. Several strategies for creating and functionalizing macroporous hydrogels have been reported. This review began with an overview of the advantages and challenges of macroporous hydrogels in the regulation of cellular behavior. In addition, advanced methods for the preparation of macroporous hydrogels to modulate cellular behavior were discussed. Finally, future research in related fields was discussed.