https://www.selleckchem.com/products/tipranavir.html Enzymatic cross-linking of polymer-catechol conjugates in the presence of horseradish peroxidase (HRP) and H2O2 has emerged as an important method to fabricate in situ-forming, injectable hydrogels. Subsequently, tissue adhesion studies using catechol-containing polymers were extensively reported. However, because of the presence of numerous variables such as polymer concentration, oxidizing agent/enzyme, and stoichiometry, the design of the polymer with optimized tissue adhesive property is still challenging. In this study, a poly(γ-glutamic acid) (γ-PGA)-dopamine (PGADA) conjugate was synthesized, and in situ hydrogels were fabricated via enzymatic cross-linking of a catechol moiety. To optimize the tissue adhesive property of the PGADA hydrogel, the effect of various factors, such as polymer concentration, catechol substitution degree (DS), HRP concentration, and H2O2 content, on the gelation behavior and mechanical strength was investigated. The gelation behavior of PGADA hydrogels was characterized using a rheometer and rotational viscometer. Also, the possibility of its use as a tissue adhesive was examined by evaluating the tissue adhesion strength in vitro and ex vivo.The successful tissue integration of a biomedical material is mainly determined by the inflammatory response after implantation. Macrophage behavior toward implanted materials is pivotal to determine the extent of the inflammatory response. Hydrogels with different properties have been developed for various biomedical applications such as wound dressings or cell-loaded scaffolds. However, there is limited investigation available on the effects of hydrogel mechanical properties on macrophage behavior and the further host inflammatory response. To this end, methacrylate-gelatin (GelMA) hydrogels were selected as a model material to study the effect of hydrogel stiffness (2, 10, and 29 kPa) on macrophage phenotype in vitro and the further host i