Tunable and fast-cured hyaluronic acid hydrogel inspired on catechol architecture for enhanced adhesion property.

Hyaluronic acid-based hydrogels have been broadly used in medical applications due to their remarkable properties such as biocompatibility, biodegradability, super hydroscopicity, non-immunogenic effect, etc. However, the inherent weak and hydrophilic polysaccharide structure of pure hyaluronic acid (HA) hydrogels has limited their potential use in muco-adhesiveness, wound dressing, and 3D printing. In this research, we developed in-situ forming of catechol-modified HA hydrogels with improved mechanical properties involving blue-light curing crosslinking reaction. The effect of catechol structure on the physicochemical properties of HA hydrogels was evaluated by varying the content (0-40 %). The as-synthesized hydrogel demonstrated rapid prototyping, excellent wetting adhesiveness, and good biocompatibility. Furthermore, an optimized hydrogel precursor solution was used as a blue light-cured bio-ink with high efficiency and good precision and successfully prototyped a microstructure that mimicked the human hepatic lobule by using DLP 3D printing method. This catechol-modified HA hydrogel with tunable physicochemical and rapid prototyping properties has excellent potential in biomedical engineering.

Preparation of silk fibroin/hyaluronic acid composite hydrogel based on thiol-ene click chemistry. / 基于巯基-çƒ¯ç‚¹å‡»åŒ–å­¦åˆ¶å¤‡ä¸ç´ è›‹ç™½/é€æ˜Žè´¨é ¸å¤åˆæ°´å‡èƒ¶.

OBJECTIVES: To design and prepare silk fibroin/hyaluronic acid composite hydrogel. METHODS: The thiol modified silk fibroin and the double-bond modified hyaluronic acid were rapidly cured into gels through thiol-ene click polymerization under ultraviolet light condition. The grafting rate of modified silk fibroin and hyaluronic acid was characterized by 1H NMR spectroscopy; the gel point and the internal microstructure of hydrogels were characterized by rheological test and scanning electron microscopy; the mechanical properties were characterized by compression test; the swelling rate and degradation rate were determined by mass method. The hydrogel was co-cultured with the cells, the cytotoxicity was measured by the lactate dehydrogenase method, the cell adhesion was measured by the float count method, and the cell growth and differentiation on the surface of the gel were observed by scanning electron microscope and fluorescence microscope. RESULTS: The functional group substitution degrees of modified silk fibroin and hyaluronic acid were 17.99% and 48.03%, respectively. The prepared silk fibroin/hyaluronic acid composite hydrogel had a gel point of 40-60 s and had a porous structure inside the gel. The compressive strength was as high as 450 kPa and it would not break after ten cycles. The water absorption capacity of the composite hydrogel was 4-10 times of its own weight. Degradation experiments showed that the hydrogel was biodegradable, and the degradation rate reached 28%-42% after 35 d. The cell biology experiments showed that the cytotoxicity of the composite gel was low, the cell adhesion was good, and the growth and differentiation of the cells on the surface of the gel were good. CONCLUSIONS: The photocurable silk fibroin/hyaluronic acid composite hydrogel can form a gel quickly, and has excellent mechanical properties, adjustable swelling rate and degradation degree, good biocompatibility, so it has promising application prospects in biomedicine.