Enhancing antibacterial properties of titanium implants through a novel Ag-TiO2-OTS nanocomposite coating: a comprehensive study on resist-killing-disintegrate approach.

Titanium (Ti) implants are widely used in orthopedic and dental applications due to their excellent biocompatibility and mechanical properties. However, bacterial adhesion and subsequent biofilm formation on implant surfaces pose a significant risk of postoperative infections and complications. Conventional surface modifications often lack long-lasting antibacterial efficacy, necessitating the development of novel coatings with enhanced antimicrobial properties. This study aims to develop a novel Ag-TiO2-OTS (Silver-Titanium dioxide-Octadecyltrichlorosilane, ATO) nanocomposite coating, through a chemical plating method. By employing a 'resist-killing-disintegrate' approach, the coating is designed to inhibit bacterial adhesion effectively, and facilitate pollutant removal with lasting effects. Characterization of the coatings was performed using spectroscopy, electron microscopy, and contact angle analysis. Antibacterial efficacy, quantitatively evaluated against E. coli and S. aureus over 168 h, showed a significant reduction in bacterial adhesion by 76.6% and 66.5% respectively, and bacterial removal rates were up to 83.8% and 73.3% in comparison to uncoated Ti-base material. Additionally, antibacterial assays indicated that the ratio of the Lifshitz-van der Waals apolar component to electron donor surface energy components significantly influences bacterial adhesion and removal, underscoring a tunable parameter for optimizing antibacterial surfaces. Biocompatibility assessments with the L929 cell line revealed that the ATO coatings exhibited excellent biocompatibility, with minimal cytotoxicity and no significant impact on cell proliferation or apoptosis. The ATO coatings provided a multi-functionality surface that not only resists bacterial colonization but also possesses self-cleaning capabilities, thereby marking a substantial advancement in the development of antibacterial coatings for medical implants.

Synthesis and in-vitro study of a novel ligustrazine diselenide as a potential chemotherapy drug for lung adenocarcinoma.

A novel ligustrazine diselenide, 1,2-bis ((3,5,6-trimethylpyrazin-2-yl) methyl) diselenide (Se2), for potential treatment on adenocarcinoma of lung cancer was successfully synthesized and fully characterized by various analytical approaches. Cytotoxic, antiproliferative and apoptosis-triggering mechanism of Se2 compound have been investigated through human lung adenocarcinoma (LUAD) cell line A549. The study found that Se2 significantly inhibit the proliferation of A549 cells in a dose-dependent manner. Flow cytometry showed that Se2 induced cell arrest and apoptosis in S and G2/M phase, and the apoptotic effect of Se2 were associated with the increase of caspase 3 and PARP-1 level approved by western blot assay. Further mechanism study results suggested that Se2 suppressed the migration,invasion and colony formation of A549 cells, significantly inhibited the PI3K/Akt/m-TOR signaling pathway. The study indicated that Se2 is a bioactive substance that can induce apoptosis of A549 cells in-vitro, and it is a potent candidate drug for LUAD.