An insight into the effect of composition for enhance catalytic performance of biogenic Au/Ag bimetallic nanoparticles

Harnessing the potential of bimetallic nanoparticles: Exploring a novel approach to address antimicrobial resistance

The growing global importance of antimicrobial resistance (AMR) in public health has prompted the creation of innovative approaches to combating the issue. In this study, the promising potential of bimetallic nanoparticles (BMNPs) was investigated as a novel weapon against AMR. This research begins by elaborating on the gravity of the AMR problem, outlining its scope in terms of the effects on healthcare systems, and stressing the urgent need for novel solutions. Because of their unusual features and wide range of potential uses, bimetallic nanoparticles (BMNPs), which are tiny particles consisting of two different metal elements, have attracted a lot of interest in numerous fields. This review article provides a comprehensive analysis of the composition, structural characteristics, and several synthesis processes employed in the production of BMNPs. Additionally, it delves into the unique properties and synergistic effects that set BMNPs apart from other materials. This review also focuses on the various antimicrobial activities shown by bimetallic nanoparticles, such as the rupturing of microbial cell membranes, the production of reactive oxygen species (ROS), and the regulation of biofilm formation. An extensive review of in vitro studies confirms the remarkable antibacterial activity of BMNPs against a variety of pathogens and sheds light on the dose-response relationship. The efficacy and safety of BMNPs in practical applications are assessed in this study. It also delves into the synergistic effects of BMNPs with traditional antimicrobial drugs and their ability to overcome multidrug resistance, providing mechanistic insight into these phenomena. Wound healing, infection prevention, and antimicrobial coatings on medical equipment are only some of the clinical applications of BMNPs that are examined, along with the difficulties and possible rewards of clinical translation. This review covers nanoparticle-based antibacterial regulation and emerging uses. The essay concludes with prospects for hybrid systems, site-specific targeting, and nanoparticle-mediated gene and drug delivery. In summary, bimetallic nanoparticles have surfaced as a potential solution, offering the public a more promising and healthier future.

Bimetallic nanocomposite (Ag-Au, Ag-Pd, Au-Pd) synthesis using gum kondagogu a natural biopolymer and their catalytic potentials in the degradation of 4-nitrophenol

Bimetallic nanoparticles (BNPs) constitute two different metal elements and exhibit relatively superior mechanistic and catalytic efficacies owing to their synergistic functions over monometallic nanoparticles. In the present study various bimetallic Ag-Au, Ag-Pd, Au-Pd nanoparticles were synthesized using a natural biopolymer gum kondagogu (GK) as a reducing and capping agent, by a simple and cost-effective method. The synthesized BNPs when characterized using UV-vis spectroscopy revealed a specific surface plasmon resonance band (SPR) of each nanocomposite. The average particle size of Ag-Au, Ag-Pd, and Au-Pd BNPs was found to be 23 ± 10.3, 21 ± 7.6, and 23 ± 9.4 nm respectively based on transmission electron microscopy analysis. Surface morphology and functional groups on the gum matrix of GK-BNPs were analyzed by XRD and FT-IR respectively. The bimetallic nanocomposites were evaluated for their catalytic reduction of 4-nitrophenol (4-NP) to 4-aminophenol in the presence of NaBH₄. The kinetic studies performed, depicted rate constants for Ag-Au, Ag-Pd, and Au-PdNPs as 0.31, 0.39, and 0.28 min^-1 respectively. The catalytic efficiencies of three bimetallic nanocomposites were of the following order Ag-Pd > Ag-Au > Au-Pd. This study establishes the catalytic potentials of the three different bimetallic nanocomposites in the reduction of 4-NP an environmental pollutant, and the impact of their synergistic property.

Synthesis of Bimetallic Gold-Silver (Au-Ag) Nanoparticles for the Catalytic Reduction of 4-Nitrophenol to 4-Aminophenol

Bimetallic gold-silver nanoparticles as unique catalysts were prepared using seed colloidal techniques. The catalytic capabilities of the nanoparticles were ascertained in the reduction of 4-nitrophenol to 4-aminophenol in the presence of sodium borohydride. Our results clearly showed that the rate of 4-NP reduction to 4-AP increased with a corresponding decrease in the diameter of the bimetallic NPs. The Au-Ag nanoparticles prepared with 5.0 mL Au seed volume indicated higher reduction activity, which was approximately 1.2 times higher than that of 2.0 mL Au seed volume in the reductive conversion of 4-NP to 4-AP. However, the monometallic NPs showed relatively less catalytic activity in the reductive conversion of 4-NP to 4-AP compared to bimetallic Au-Ag nanoparticles. Our studies also reinforced the improved catalytic properties of the bimetallic Au-Ag nanoparticles structure with a direct impact of the size or diameter and relative composition of the bimetallic catalytic nanoparticles.