This study marks the first ever attempt at the successful fabrication of a novel reactive membrane to combat fouling through layer-by-layer (LBL) surface modification with polyelectrolyte (PE), followed by anisotropic triangular silver nanoparticles (TSNP). The morphology and the presence of TSNP on the membrane was confirmed by HR-TEM, FE-SEM and XPS. The charge density of the novel membrane (PE-TSNP) was increased 15.6 fold, as a result of the sharp-tip morphology of the TSNP forming tip-based "hot spots" on the membrane surface and high-atom-density active facets, which also enhanced the membrane hydrophilicity by 36%. Owing to these improved features, the novel membrane displayed remarkable antibacterial and anti-adhesion properties by achieving 100% bactericidal effect against high initial bacterial concentration (10 7 CFU mL À1 ). The membrane flux was improved by 31% while retaining a high flux recovery rate of 98.2% against biofouling. The membrane also mitigated organic and bio-organic fouling by maintaining high flux recovery rates of 96% and 95% respectively. As compared with a spherical silver nanoparticle modified membrane (PE-SSNP), the PE-TSNP membrane was 25.7% more hydrophilic and achieved 10% higher bacterial killing. Moreover, the novel membrane displayed 9.5%, 11.6%, and 14% higher flux recovery rates than that of the PE-SSNP membrane against biofouling, organic and bio-organic fouling respectively. Furthermore, the novel membrane retained a long-term biocidal capability of 93% even after 4 months of successive tests. ICP-MS revealed silver ion leaching of 4 mg L À1 and the total silver loss of 14% from the PE-TSNP membrane after 14 days. Fig. 1 (a) Absorption spectrum of spherical silver nanoparticles and triangular silver nanoparticles. (b) HR-TEM image of the triangular silver nanoparticles. The inset shows the morphology of the single triangular silver nanoparticle. (c) XRD spectra of TSNP. Planes at {111}, {200}, {220} indicates face-centered cubic (fcc) lattice structure of crystalline Ag. (d) Shows the XPS spectrum of the PE-TSNP2 modified membrane. Distinct Ag3d peaks indicating the presence of Ag on the membrane surface. This journal isFig. 7 Long-term membrane performance (a) antibacterial rate of the PE-TSNP2 modified membranes against E. coli. (b) FE-SEM image of PE-TSNP2 membrane after fouling in long-term studies, showing the presence of triangular silver nanoparticles on the membrane.This journal is

Study investigated single element noble metal nanoparticle shape-dependent ROS generation and quantification, and investigated selective ROS species action on microbes.

A microbiological and sanitation survey of ready-to-eat (RTE) food samples, cutlery, utensils, and hands of food handlers, food preparation surfaces, serving counters, washing areas, and refrigerator handles were conducted. The samples were collected using environmental swabs, and these samples were analyzed using standard plating techniques. Samples were characterized after aerobic plate counts (APC) and isolated for mesophilic aerobic bacteria (MAB), total coliforms, Staphylococcus aureus, Escherichia coli., Salmonella spp., Shigella spp., Pseudomonas spp., Enterobacter spp., Klebsiella spp., and yeast. This study suggested that good-hygiene practices can minimize bacterial counts, thereby decreasing the reservoirs for bacterial contamination. It also improves the hygienic condition of RTE-foods in the cafeteria of Universities.

Gold nanoparticles (AuNPs) were synthesized using citrate reduction, also known as the Turkevich method. The AuNPs were compared with the commercially available product and later subjected to characterization. The AuNPs were 13 nm in diameter with a 2.7 × 108 M−1cm−1 extension coefficient. The calculated concentration was 5.1 nM through the Beer–Lambert law using UV–vis absorbance spectra. Further detailed characterization was applied, such as scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), elemental analysis using electro and DLS instruments, energy-dispersive X-ray spectroscopy (EDS), XRD, and Zeta potential. The synthesized AuNPs had a higher UV-absorbance peak of 0.93 in comparison to commercially available nanoparticles at 5.8 identical conditions. The characterization confirmed successful fabrication of colloidal-citrate-capped AuNPs and their dispersed and aggregated state with induced salt concentration. The shape and morphology were confirmed through XRD, showing a face-centered cubic lattice of {111}, confirmed at 38.1 round shape, and a crystalline lattice. AuNPs tend to be applied in sensing, detection, drug delivery, pharmaceuticals, and other applications in the environment and materials. Other applications include environmental contaminant detection, colorimetric sensors, antimicrobial applications, biosensing and drug delivery, tissue engineering, nanomedicines, optoelectronics, and catalysts.