Silver-doped diamond-like carbon (Ag-DLC) films offer low residual stress, good adhesion, and excellent wear resistance, and thus are promising materials for surface modification of joint prostheses. Further, as proteins are the most abundant component of joint fluid, the wear performance of Ag-DLC films in protein environments warrants investigation. We prepared DLC and 10.0 at.% Ag-DLC films using hybrid deposition technique by combining high-power pulsed magnetron sputtering and high-power pulsed plasma-enhanced chemical vapor deposition. The wear performance of the films was tested using bovine serum albumin (BSA) solution. A biofilm of denatured proteins formed at the friction interface of the Ag-DLC film, which improve wear resistance. Subsequent protein adsorption, Ag⁺ ions release, and spectroscopic evaluation of the interaction between Ag⁺ ions and BSA molecules revealed the mechanism of biofilm formation. Ag doping promoted the protein adsorption on film surface and friction interface of Ag-DLC films. Meanwhile, Ag-DLC films released Ag⁺ ions when exposed in physiological solutions. The released Ag⁺ ions break the hydrogen bonds and disulfide bonds in proteins and transform the α-helix structure to β-sheet and β-turn structure, thus unfolding the protein, exposing the inner hydrophobic groups, and inducing protein deposition and biofilm formation. The study elucidates the biofilm formation mechanism at the friction interface of Ag-DLC films and counterparts and can aid in design of hardwearing joint implants.

掺银类金刚石碳（Ag-DLC）薄膜具有低残余应力、良好的粘附性和优异的耐磨性，因此是用于关节假体表面改性的有前途的材料。此外，由于蛋白质是关节液中含量最丰富的成分，因此蛋白质环境中 Ag-DLC 薄膜的磨损性能值得研究。我们通过结合高功率脉冲磁控溅射和高功率脉冲等离子体增强化学气相沉积，使用混合沉积技术制备了 DLC 和 10.0 at.% Ag-DLC 薄膜。使用牛血清白蛋白（BSA）溶液测试薄膜的耐磨性能。在 Ag-DLC 膜的摩擦界面处形成的变性蛋白质生物膜，可提高耐磨性。随后的蛋白质吸附，Ag ⁺离子释放和 Ag ⁺离子与 BSA 分子之间相互作用的光谱评估揭示了生物膜形成的机制。Ag掺杂促进了Ag-DLC薄膜表面和摩擦界面上的蛋白质吸附。同时，Ag-DLC 薄膜暴露在生理溶液中时会释放 Ag ⁺离子。释放的Ag ⁺离子破坏蛋白质中的氢键和二硫键，将α-螺旋结构转化为β-折叠和β转结构，从而展开蛋白质，暴露内部疏水基团，并诱导蛋白质沉积和生物膜形成。该研究阐明了 Ag-DLC 膜和对应物摩擦界面的生物膜形成机制，有助于设计耐磨关节植入物。