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Hydrogel coatings, with natural tissue‐like mechanical and biological compatibility, demonstrate promise for bulk material applications. However, existing coating methods lack efficiency and control, especially when dealing with complex geometries, diverse substrate materials, and varying sizes. In this study, an enzyme‐immobilized surface‐catalyzed cross‐link approach is proposed for the growth of hydrogel coatings on multiple substrates, accommodating various materials and shapes. The hydrogel coating is formed through the catalytic action of interface‐immobilized enzymes, which induce the crosslinking of hyaluronic acid, and its mechanical properties are further enhanced by introducing a secondary polyacrylamide network. This approach enables the controlled growth of conformal double network hydrogel coatings with a desired thickness on a wide range of substrate surfaces and devices. Notably, the hydrogel coating exhibits remarkable lubricity and anti‐thrombotic properties, especially desire for medical intervention devices. This advancement offers a universal route to impart biocompatible soft interfaces to bulk materials or devices. [ABSTRACT FROM AUTHOR]

Population aging and the development of transcatheter aortic valve replacement boost the implantation of bioprosthetic heart valves (BHVs) in patients worldwide. However, the traditional glutaraldehyde cross‐linked BHVs fail within 12–15 years mainly due to leaflet tear and calcification defects. In this study, a novel visible light–induced cross‐linking of the porcine pericardium (PP) was realized by the photo‐oxidation of the furfuryl‐modified PP in the presence of Rose Bengal. The resulting material showed comparable collagen stability with the glutaraldehyde cross‐linked PP and appropriate biomechanical properties such as tensile strength, modulus, and elongation, suggesting that this material could meet the general requirement for BHVs. Besides, this cross‐linked PP showed significantly improved cytocompatibility compared with the Glut–cross‐linked PP, with no cytotoxicity to L929 cells and the ability to support HUVECgrowth. Meanwhile, this material showed superior anti‐tearing performance and much less calcification than the Glut–cross‐linked PP in hope of reducing the risk of BHV failure. Considering these results, the visible light–induced cross‐linking method proposed in this study could provide a promising way to construct a biocompatible and robust biomaterial for the fabrication of the BHV. [ABSTRACT FROM AUTHOR]

Bioprosthetic heart valve (BHV) replacement is increasingly used for treating valve‐related diseases worldwide but the current commercially used BHVs treated with glutaraldehyde (Glut) often failed within 12–15 years due to degradation, thrombosis, inferior biocompatibility, and calcification. Herein, 3‐glycidyloxypropyl trimethoxysilane (GPTMS) was used to crosslink porcine pericardium (PP) at the concentration (vol/vol) of 0.25%, 1%, 2%, and 4% and their performance for potential application in BHVs was evaluated. The crosslinking mechanism mainly involved the ring‐opening of epoxide by amine attack and silanol poly‐condensation. The stability of collagen in higher concentration (1%, 2%, and 4%) GPTMS crosslinked PPs (GPTMS‐PPs) was clearly increased. GPTMS‐PPs showed no cytotoxicity and supported the growth of endothelial cells while Glut‐PP did not. GPTMS‐PPs were less prothrombotic than Glut‐PP. GPTMS‐PP crosslinked at 1% concentration showed comparable mechanical properties to Glut‐PP while had better anti‐tearing performance. The subcutaneous implantation in rat for 30 days showed that GPTMS crosslinking was able to effectively inhibit the calcification of BHV. [ABSTRACT FROM AUTHOR]

The failures of glutaraldehyde (GLUT) cross‐linked bioprosthetic heart valves (BHVs) are mainly due to degeneration and calcification. In this study, we developed a new preparation strategy for BHVs named as "HPA/EDC/EGCG" that utilized 3,4‐hydroxyphenylpropionic acid (HPA)‐conjugated pericardium, epigallocatechin gallate (EGCG), and horseradish peroxidase (HRP)/hydrogen peroxide (H2O2) enzymatic cross‐linking. HPA–pericardium conjugation was done by carbodiimide coupling reaction using 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC) and N‐hydroxysuccinimide (NHS). Then HPA‐conjugated pericardium was cross‐linked by HRP/H2O2 enzyme‐catalyzed oxidation. The feeding ratios of HPA and EGCG were optimized. The consumption of amino groups, collagenase and elastase degradation in vitro, biomechanics, extracellular matrix stability, and calcification of HPA‐/EDC‐/EGCG‐treated pericardiums were characterized. We demonstrated that HPA‐/EDC‐/EGCG‐treated pericardiums had better elastin stabilization and less calcification. EGCG and enzymatic cross‐linking treated pericardiums showed improved mechanical properties. This new EGCG and enzymatic cross‐linking strategy would be a promising method to make BHVs with better elastin stability and anti‐calcification property. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1551–1559, 2019. [ABSTRACT FROM AUTHOR]