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A new green system of biogenic Ni/DFNS@Pd nanoparticles for the production of 2-oxo-2-phenylethylbenzoate and cyclic carbonates by using the oxidative carboxylation of alkenes. [Display omitted] • Ni/DFNS@Pd nanoparticles created by Desulfovibrio alaskensis were remarkably active nanocatalysts. • The catalyst's properties were specified by VSM, TGA, TEM, XRD, and EDX analyses. • Ni/DFNS@Pd nanostructures were deployed to oxidation of styrenes with carbon dioxide to cyclic carbonates. In this paper, we report highly atom-selective and efficacious oxidation of styrenes with carbon dioxide to cyclic carbonates in the appearance of Ni/DFNS@Pd as a magnetic nanocatalyst (MNPs). For convenient detachment of the catalyst by an exterior magnetic domain, the dendritic fibrous nanosilica (DFNS) outer layer was covered with nickel to magnetize the DFNS. Then, the palladium nanoparticles on the outer layer of Ni/DFNS were diminished. In spite of the possibility of using these biological processes in the sustainable recapturing of vital metals (e.g. Pd), the catalytic function of biosynthesised MNPs has not yet been scrutinized. Here, instead of a chemical approach, microorganisms were utilized as catalysts for the generation of Pd nanoparticles in a biological procedure. These biogenic magnetic nanoparticles have been utilized for the first time as a reusable catalyst with an exterior magnet. The catalyst's attributes were distinguished by a variety of methods, including scanning electron microscopy (SEM), energy dispersive X-ray (EDX), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), and vibrating sample magnetometer (VSM) analyses. Biogenized Ni/DFNS@Pd was generated as a heterogeneous catalyst to compete with a homogeneous structure. This robust metal catalyst with great accessibility level and reusability was generated by anaerobic bacteria. Examining different concentrations of the catalyst showed that the selectivity and efficiency of the reaction are significantly affected by the concentration of the catalyst. Heterogeneous reaction compounds did not cause any negative effects. The products were eliminated from the catalyst without any problems and the catalyst was employed many times without a conspicuous loss in selectivity and activity. [ABSTRACT FROM AUTHOR]

Objectives: This study investigated the antibacterial, cytotoxicity, and mechanical properties of a dental adhesive modified with quaternary ammonium monomer ((2-acryloyloxyethyl)dimethyldodecylammonium bromide) and cross-linker (bis(2-acryloyloxyethyl)methyldodecylammonium bromide). Materials and methods: Monomer (M), cross-linker (C), or a combination of these (M + C) were incorporated into adhesive Adper Single Bond Plus (SB) in 5, 10, or 25% (as wt%). A colony-forming unit and MTT assays were used to evaluate antibacterial properties against Streptococcus mutans and cell viability. Resin-dentin beams (0.9 ± 0.1 mm2) were evaluated for micro-tensile bond strength (μTBS) after 24 h, 6 months, and 3 years. Hourglass specimens were evaluated for ultimate tensile strength (UTS) after 24 h, 1 week, and 6 months. Micro-hardness measurements after softening in ethanol were taken as an indirect assessment of the polymer cross-linking density. Kruskal-Wallis, one-way ANOVA, two-way ANOVA, and Student's t test were used for analysis of the antibacterial, cytotoxicity, μTBS, UTS, and hardness data, all with a significance level of p < 0.05. Results: 10%M and 25%M demonstrated a significant reduction in S. mutans relative to SB (p < 0.001). No differences in cytotoxicity were detected for any of the groups. After 6 months, no changes in μTBS were shown for any of the groups. After 3 years, all groups evidenced a significant decrease in μTBS (p < 0.05) except 5%M, 5%C, and 5%M + 5%C. All groups demonstrated either stable or significantly increased UTS after 6 months. Except for the cross-linker groups, a significant decrease in micro-hardness was shown for all groups after softening in ethanol (p < 0.05). Conclusions: A 5–10% of monomer may render the resin antibacterial without a compromise to its mechanical and bonding properties. Clinical relevance: Biomodification of a resin adhesive with an antibacterial monomer and cross-linker may help improve the life span of adhesive restorations. [ABSTRACT FROM AUTHOR]