Biomaterials used for bone implants should be characterized by good corrosion resistance, appropriate mechanical and electrical properties, high metallurgical quality, biocompatibility, abrasion resistance, and relatively low production costs. Currently used titanium alloys are being replaced by materials with better biocompatibility, so-called new-generation titanium alloys containing elements such as vanadium or niobium. These alloys, with the addition of Zr, Fe, or Ta, give Young's modulus values approximating that of bone, thus further improving the biocompatibility of the biomaterial. The aim of this study was to assess the impact on its physicochemical and mechanical properties of modifying Ti-13Nb-13Zr alloy with a titanium nitride (TiN) layer using PVD. The knowledge obtained has practical significance for the use of this type of surface modification for various types of miniaturized implants used, for example, in the skeletal system. As part of the assessment of the physicochemical properties of the resulting surface layers, microscopic observations (SEM), potentiodynamic tests, impedance tests, surface wettability tests, scratch tests, and layer abrasion tests were performed. Based on the results obtained, various physicochemical properties of the modified alloy were recorded, depending on the surface modification process. As a result, better properties were noted with respect to corrosion resistance, especially for the tribological properties and the surface resistance to abrasion. The knowledge obtained from this research has practical significance for the use of this type of surface modification for various types of miniaturized implants used in the skeletal system.

Low-temperature plasma (LTP) activation is increasingly used as a surface modification technique to enhance the wettability and biological performance of metallic implants. However, the stability of plasma-induced surface changes and their interaction with standard sterilisation procedures remain insufficiently understood. This study aimed to evaluate the effects of LTP activation, steam sterilisation, and their combination with the wettability of metallic implant materials, as well as the temporal stability of these effects. Samples manufactured from Ti6Al4V sheet, additively manufactured Ti6Al4V, and additively manufactured cobalt–chromium alloy were subjected to low-temperature plasma activation, steam sterilisation, or both procedures. Surface wettability was assessed by measuring the contact angle of canine blood droplets immediately after treatment and over a five-day observation period. Low-temperature plasma activation resulted in a substantial reduction in the contact angle for all tested materials, indicating a pronounced increase in surface wettability. However, this effect gradually diminished over time. Steam sterilisation alone moderately improved wettability and showed relatively stable effects. When steam sterilisation was applied after plasma activation, the plasma-induced enhancement was significantly attenuated and rapidly lost during storage. These findings demonstrate that while LTP activation effectively improves surface wettability, its benefits are highly time-dependent and strongly influenced by subsequent sterilisation. Plasma activation should therefore be performed immediately before implantation or combined with sterilisation and storage strategies that preserve surface modifications.

Restenosis is the main cause of failure after stent implantation during angioplasty. The localized, sustained delivery of an antirestenotic drug may reduce smooth muscle cell (SMCs) proliferation and thereby limit neointimal hyperplasia. The aim of this study was to develop degradable sirolimus-eluting polymer coatings that can be applied on bioresorbable polymer-based scaffolds via an ultrasonic coating system. This is a novel approach because the detailed analysis of the coating procedure on bioresorbable polymeric scaffolds with the use of an ultrasonic system has not been reported thus far. It has been observed that the ultrasonic technique facilitates formation of a smooth coating, well-integrated with the scaffold. However, the drug dose is affected by the concentration of the coating solution and the number of layers. Therefore, these parameters can be used for tailoring the drug dose and release process. Although all types of the developed coatings provided sirolimus elution for at least 3 months, a more uniform, diffusion-controlled release profile was observed from coatings obtained from the 1.0% polymeric solution. The released drug showed antiproliferative activity against vascular SMCs, without any hemolytic or thrombogenic effects. The results of the study may be advantageous for further progress in the development and medical translation of polymeric vascular scaffolds with antirestenotic activity.