Gelatin Hydrogel Combined with Polydopamine Coating To Enhance Tissue Integration of Medical Implants

Abstract

Soft tissue integration of medical implants is important to prevent bacterial infection and implant failure. A bioadhesive that forms firm binding between the implant and the surrounding tissue and facilitates the wound-healing process will be a great tool to establish the desired tissue-implant integration. In this project, we introduce a novel method that can be used to enhance integration between any implant material and any tissue using an enzyme-crosslinked gelatin hydrogel combined with polydopamine (PDA) coating. PDA coating was shown to enhance the binding between the gelatin hydrogel and three model implant materials – aluminum, poly(methyl methacrylate) (PMMA) and titanium. When combined with the gelatin hydrogel, pig cornea tissue adhered more strongly to the PDA coated surfaces than to the uncoated surfaces. The enzyme-crosslinked gelatin hydrogel was non-cytotoxic to human dermal fibroblasts and it also allowed the cells to adhere and proliferate. Altogether, the results indicate that the combination of PDA coating with gelatin hydrogel can be used to enhance the integration of various medical implants.

The physico-chemistry of adhesions of protein resistant and weak polyelectrolyte brushes to cells and tissues

“…The non-specific interactions between polymeric biomaterials and soft tissues play an important role in the performance of implants, tissue engineering scaffolds and drug delivery systems. [1][2][3][4][5] Physico-chemical interactions are particularly important in regulating the strength of bioadhesives, such as skin adhesives for surgical applications, [6][7][8] hydrogels for epicardial placement and stem cell delivery, 9 soft tissue adhesion for tissue regeneration 3,4 or mucoadhesives for dental adhesion. 10,11 Although a range of chemical functions and molecules have been introduced in biomaterials to promote covalent coupling and adhesion to soft tissues, the control and regulation of non-specific physicochemical interactions with surrounding tissues post-implantation and delivery can play an important role and even dominate adhesion performance.…”

Performance of Polydopamine Complex and Mechanisms in Wound Healing

“…Therefore, covalent bonds are also required to form permanent crosslinks, resulting in higher crosslinking densities to produce better mechanical strength [ 26 ]. Ding et al [ 27 ] added PDA to the gelatin hydrogel and reported that the weakest adhesion connection is the hydrogel interface in the uncoated gel material. In contrast, the weakest adhesion link in the coated PDA material is the cohesion of the hydrogel, which proves that the quinones of PDA forms a covalent bond with the lysine and arginine residues in gelatin.…”

Current Advances in the Utilization of Polydopamine Nanostructures in Biomedical Therapy

“…[107] In a different study, Pacelli et al [108] employed PDA coating to enhance the adsorption of dexamethasone onto a hydrogel arising from alginate and gelatin methacrylamide, which was later used as a scaffold for the modulation of osteogenic differentiation. In addition, the use of a complex composed of PDA coating and a cross-linked hydrogel to improve the association between medical implants and internal tissues was described by Dinh et al [109] Very recently, PDA films were successfully coated onto various substrates including polyetheretherketone (PEEK), Ti6Al4 V, and HAP. [110] The coated substrates were shown to improve the attachment, growth, and differentiation of bone Figure 3.…”