Work

Precision depth-controlled isolated silver nanoparticle-doped diamond-like carbon coatings with enhanced ion release, biocompatibility, and mechanical performance

Year: 2024

Type: article

Abstract: Silver doped diamond-like carbon (Ag/DLC) coatings are in high demand for biomedical applications such as artificial implants , surgical instruments, and medical devices . However, recent reports indicate that the excess Ag concentration required in typically made Ag/DLC coatings significantly reduces their mechanical performance and biocompatibility. Here, we propose a novel single-step approach to precisely dope small quantities of Ag in the form of isolated nanoparticles embedded at defined depths in a DLC matrix. This new Ag/DLC coating architecture is designed to release controlled Ag ion levels to fight infection in the early post-surgery stages, while a confined Ag amount maintains the excellent mechanical and biocompatibility performance of the underlying DLC coating when compared to typically made Ag/DLC coating designs. Coatings of pure DLC, typically made Ag/DLC with Ag doped throughout the carbon matrix and the new Ag/DLC design with precise Ag doping, are made using a modified magnetron sputtering system. The coatings are characterised for structural, mechanical, ion leaching, and biocompatibility profiles against L929 fibroblast cells. Results indicate that the new Ag/DLC coating requires only 2 at.% Ag to release a similar level of Ag ions (∼0.6 ppm) to a typical Ag/DLC coating with a much higher Ag content of 17 at.%. The new Ag/DLC coating design also outperforms the typical design with a 63 % increase in hardness, 100 % higher Young's modulus , and 21 % higher biocompatibility. The enhanced biomechanical performance of the proposed new Ag/DLC architecture could have significant potential for coating of future medical devices.

Source: Surface and Coatings Technology

DOI: 10.1016/j.surfcoat.2024.131281

Authors: Abdul Wasy Zia, Ioannis Anestopoulos, Leon Bowen, Mihalis I. Panayiotidis, Martin Birkett

Institutions: Heriot-Watt University, Cyprus Institute of Neurology and Genetics, Durham University, Northumbria University

Language: English

Topic: Diamond and Carbon-based Materials Research

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,770