Ti-Containing Mesh Implants Modified by Heterostructures Based on Noble Metal: Fabrication and Study of Biological Activity

Ti-based mesh implants (“titanium silk” TiS and NiTi alloy) offer excellent tissue integration for oncologic surgery but lack intrinsic antibacterial activity. To address this, we fabricated Ag nanoparticles and Ag/M (M = Pt, Au) heterostructures on mesh surfaces via vapor-phase deposition, with noble metal sublayers functionalized by Ag nanofilms and nanoclusters. The modified implants were comprehensively characterized using SEM, AFM, XPS, and ICP-AES and evaluated through in vitro biocompatibility and antibacterial assays. The functional performance of the heterostructures is governed by two key phenomena: a chemical sublayer effect and a geometry-dependent substrate effect, which together dictate ion release kinetics. The Ag/Au interface sustains Ag+ release, whereas Ag/Pt drives rapid Ag+ dissolution. All heterostructures demonstrated effective antibacterial activity against planktonic S. aureus within 24 h. Key factors responsible for reduction in the more resilient P. aeruginosa on the Ag/M heterostructures were hypothesized. Cytotoxicity was dictated by the released ion cocktail: Ag/Pt/NiTi exhibited elevated toxicity which may be associated with the combined release of Ag+, Ni2+ and Pt2+, whereas all Ag/Au-based heterostructures showed excellent biocompatibility (viability 75–108%). Notably, gold sublayers were associated with elevated IL-10 secretion by 72 h. Based on overall biological performance, Ag/Au heterostructures offering sustained antibacterial activity against planktonic bacteria, low cytotoxicity, and a cytokine profile that may be favorable for long-term integration are promising candidates for mesh implants. Also, h-Ag/Pt/TiS showed an optimal balance between rapid antibacterial action and biocompatibility and therefore appears to be a suitable candidate for further in vivo investigation.