Noble Metals for Modern Implant Materials: MOCVD of Film Structures and Cytotoxical, Antibacterial, and Histological Studies

Abstract

This work is aimed at developing the modification of the surface of medical implants with film materials based on noble metals in order to improve their biological characteristics. Gas-phase transportation methods were proposed to obtain such materials. To determine the effect of the material of the bottom layer of heterometallic structures, Ir, Pt, and PtIr coatings with a thickness of 1.4–1.5 μm were deposited by metal–organic chemical vapor deposition (MOCVD) on Ti6Al4V alloy discs. Two types of antibacterial components, namely, gold nanoparticles (AuNPs) and discontinuous Ag coatings, were deposited on the surface of these coatings. AuNPs (11–14 nm) were deposited by a pulsed MOCVD method, while Ag films (35–40 nm in thickness) were obtained by physical vapor deposition (PVD). The cytotoxic (24 h and 48 h, toward peripheral blood mononuclear cells (PBMCs)) and antibacterial (24 h) properties of monophase (Ag, Ir, Pt, and PtIr) and heterophase (Ag/Pt, Ag/Ir, Ag/PtIr, Au/Pt, Au/Ir, and Au/PtIr) film materials deposited on Ti-alloy samples were studied in vitro and compared with those of uncoated Ti-alloy samples. Studies of the cytokine production by PBMCs in response to incubation of the samples for 24 and 48 h and histological studies at 1 and 3 months after subcutaneous implantation in rats were also performed. Despite the comparable thickness of the fibrous capsule after 3 months, a faster completion of the active phase of encapsulation was observed for the coated implants compared to the Ti alloy analogs. For the Ag-containing samples, growth inhibition of S. epidermidis, S. aureus, Str. pyogenes, P. aeruginosa, and Ent. faecium was observed.

Carbon Nanofibers versus Silver Nanoparticles: Time-Dependent Cytotoxicity, Proliferation, and Gene Expression

“…Silver nanoparticles (AgNPs) have been studied in greater depth than CNFs. They are also cost-effective and possess excellent antimicrobial properties [ 20 , 21 , 22 , 23 , 24 ]. In fact, AgNPs are already broadly used in wound dressings for healing processes and treating burns in biomedicine as well as in the food and textile industries and in paints, household products, catheters, implants, and cosmetics and in combination with many types of materials to prevent infection [ 25 , 26 , 27 , 28 , 29 , 30 ].…”

Biological Studies of New Implant Materials Based on Carbon and Polymer Carriers with Film Heterostructures Containing Noble Metals

“…determination (Kofler table). The detailed synthesis and identification of the gold precursor were described in our previous work [ 24 ].…”

“…In this method, volatile precursors (noble metal complexes with organic ligands) are heated in a vacuum reactor to transfer them to the gas phase and then transported in a carrier gas flow to the deposition zone, where an activated chemical reaction of decomposition of precursor vapors occurs on the heated surface of the implant with the formation of a metal coating and removal of gaseous reaction products. This method has already been successfully used and described in detail in our previous publication [ 24 ]. The method of physical vapor deposition (PVD) was used to deposit silver nanoparticles onto the film structures.…”

“…In our previous work [ 24 ], we analyzed the dependence of the biological properties of implants made of titanium and its alloys and covered with thin film structures of iridium, platinum, and gold and silver nanoparticles on the composition of these structures.…”

Anti-bacterial activity of gold nanocomposites as a new nanomaterial weapon to combat photogenic agents: recent advances and challenges

“… 91 Innovative research revealed that synthesized nanocomposites (Ag/Pt, Ag/Ir, Ag/PtIr, Au/Pt, Au/Ir, and Au/PtIr) presented antibacterial and cytotoxic activity. 92 High antibacterial activity was presented by AuNPs synthesized via epigallocatechin 3-gallate. The produced nanocomposites showed antibacterial properties against S. aureus , Enterococcus faecalis , P. aeruginosa and E. coli ( Table 3 ).…”