Mineralized collagen coatings formed by electrochemical deposition

Abstract

Understanding and controlling the process of electrochemical deposition (ECD) of a mineralized collagen coating on metallic orthopedic implants is important for engineering highly bioactive coatings. In this work, the influence of different ECD parameters was investigated. The results showed that the mineralization degree of the coatings increased with deposition time, voltage potential and H2O2 addition, while chitosan addition led to weakening of mineralization, heavy mineralization resulted in a porous coating morphology. Furthermore, two typical coatings, dense and porous, were analyzed to investigate their microstructure and evaluated for their cytocompatibility; the dense coating showed better osteoblast adhesion and proliferation. Based on our understanding of how the different coating parameters influenced the coating, we proposed an ECD process in which the pH gradient near the cathode and the collagen isoelectric point were suggested to play crucial roles in controlling the mineralization and morphology of the coatings. The proposed ECD process may offer a guide for controlled deposition of a desired bioactive coating.

Alternating potentials assisted electrochemical deposition of mineralized collagen coatings

“…According to the mechanism of constant potential deposition proposed by our previous work [15] , collagen fibrils begin to self-assemble and mineralize in the vicinity of the substrate due to an increase in pH derived by H2O electrolysis under applying negative potential. However, the pH at vicinity of the substrate has a gradient variation.…”

“…Previously, we have successfully prepared the mineralized coatings by electrochemical deposition at constant potential to bond the collagen fibrils to the metal substrate by calcium phosphates [15] , with a calcium phosphate covered and porous surface. However, the highly mineralized collagen might not be conductive to the cellular response and beneficial to the further loading of biofactors, such as rhBMP-2, which has been proven as an effective biofactor for ossointegration.…”

Preparation, Characterization, and Preliminary Biocompatibility Evaluation of Carbon Ion-Implanted Silicone Rubber

“…At present, the surface modiication of silicone rubber can be treated by plasma treatment, grafting copolymerization, and biomimetic coating, but there are some defects, such as the steps were cumbersome and substrate temperature and the conditions are not easy to control [11][12][13][14][15][16][17][18]. In this study, the technology of ion implantation which is mainly used in metal and semiconductor materials is introduced into the surface modiication of silicone rubber material.…”

Surface Modification of Silicone Rubber by Ion Implantation to Improve Biocompatibility

“…Among these methods, the surface modification of biomaterials is an economical and effective method to achieve biocompatibility and biofunctionality while preserving the favorable characteristics of the biomaterial, such as particular mechanical properties and thermal stability. Surface modifications, such as ion implantation [16][17][18], sintering [19], electrochemical deposition [20], and the sol-gel coating method, are common [21]. Among these surface modification methods, ion implantation has become a notably useful method because of its ease of operation and convenience [22][23][24][25].…”