Size-controlled synthesis of La and chitosan doped cobalt selenide nanostructures for catalytic and antibacterial activity with molecular docking analysis.

Co-precipitation method was adopted to synthesize ternary heterostructure catalysts La/CS-CoSe NSs (lanthanum/chitosan­cobalt selenide nanostructures) without the use of a surfactant. During synthesis, a fixed amount (3 wt%) of CS was doped with 2 and 4 wt% La to control the growth, recombination rate and stability of CoSe NSs. The doped samples served to enhance the surface area, porosity and active sites for catalytic degradation of rhodamine B dye and antibacterial potential against Staphylococcus aureus (S. aureus). Additionally, the synthesized catalysts were examined for morphological, structural and optical characteristics to assess the influence of dopants to CoSe. XRD spectra verified the hexagonal and cubic structure of CoSe, whereas the porosity of the undoped sample (CoSe) increased from 45 to 60 % upon incorporation of dopants (La and Cs). Among the samples analyzed during this study, 4 % La/CS-CoSe exhibited significant bactericidal behavior as well as the highest catalytic reduction of rhodamine B dye in a neutral environment. Molecular docking analysis was employed to elucidate the underlying mechanism behind the bactericidal activity exhibited by CS-CoSe and La/CS-CoSe NSs against DHFRS. aureus and DNA gyraseS. aureus.

Dye Degradation, Antimicrobial Activity, and Molecular Docking Analysis of Samarium-Grafted Carbon Nitride Doped-Bismuth Oxobromide Quantum Dots.

Various concentrations of samarium-grafted-carbon nitride (Sm-g-C3N4) doped-bismuth oxobromide (BiOBr) quantum dots (QDs) are prepared by the co-precipitation method. Elemental evaluation, morphological, optical, and functional group assessment are studied employing characterization techniques. Based on the XRD pattern analysis, it is determined that BiOBr exhibits a tetragonal crystal structure. The electronic spectroscopy revealed an absorption peak for BiOBr at 315 nm and the bandgap energy (E g) decreasing from 3.9 to 3.8 eV with the insertion of Sm-g-C3N4. The presence of vibrational modes related to BiOBr at 550 cm-1 is confirmed through FTIR spectra. TEM revealed that pure BiOBr possessed non-uniform QDS, and agglomeration increased with the addition of Sm-g-C3N4. The catalytic performance of Sm-g-C3N4 into BiOBr (6 mL) in a neutral medium toward rhodamine B exhibited excellent results (99.66%). The bactericidal activity is evaluated against multi-drug resistance (MDR) Escherichia coli once the surface area is increased by dopant and the measured inhibition zone is assessed to be 3.65 mm. Molecular docking results supported the in vitro bactericidal potential of Sm-g-C3N4 and Sm-g-C3N4 doped-BiOBr as DNA gyraseE. coli inhibitors. This study shows that the novel Sm-g-C3N4 doped-BiOBr is a better catalyst that increases specific semiconductor's catalytic activity (CA).

La-Doped CeO2 Quantum Dots: Novel Dye Degrader, Antibacterial Activity, and In Silico Molecular Docking Analysis.

The current work demonstrates a novel synthesis of different concentrations of La-doped (2, 4, and 6 wt %) CeO2 quantum dots (QDs) using a hydrothermal approach. This research aimed to examine the dye degradation efficiency, antibacterial activity, and in silico molecular docking analysis of La-doped CeO2 QDs. The structure, elemental composition, optical properties, d-spacing, and morphological features of QDs were examined using various methods. XRD spectra exhibited the cubic structure of CeO2, and the crystallinity was suppressed upon La doping. TEM revealed the formation of cubic-shaped QDs of CeO2, and the incorporation of La decreased agglomeration. UV-vis absorption spectra showed a red shift upon La doping, assigned to a decrease in band gap energy. 6% La-doped CeO2 showed significant antibacterial activity against Escherichia coli at higher concentrations in comparison to ciprofloxacin. La-CeO2 was proposed as a putative inhibitor of ß-lactamase E. coli and DNA gyrase E. coli relying on the outcomes of a molecular docking analysis that was in improved accord with in vitro bactericidal activity. Moreover, the prepared QDs exhibited a remarkable photocatalytic degradation of methylene blue in a basic medium.

Assessment of catalytic, antimicrobial and molecular docking analysis of starch-grafted polyacrylic acid doped BaO nanostructures.

The removal of cationic dyes from water has received a great attention of researchers considering their influence on environment and ecosystem. In current work, starch-grafted-poly acrylic acid (St-g-PAA) doped BaO nanostrucutures have been synthesized by co-precipitation approach. The aim of this research was to reduce the harmful methylene blue dye and evaluate the antibacterial activity of St-g-PAA doped BaO. XRD spectra exhibited the tetragonal structure of BaO and no variations occurred upon doping. The optical properties of St-g-PAA doped BaO have been evaluated by UV-Vis spectrophotometer. The existence of a dopant in the product was verified using EDS spectroscopy. TEM revealed the formation of cubic-shaped NPs of BaO and upon the addition of St-g-PAA, a few nanorod-like structures. The higher concentration of St-g-PAA doped BaO exhibit a remarkable reduction of methylene blue in a basic environment. Furthermore, St-g-PAA doped BaO revealed higher antimicrobial efficacy against Staphylococcus aureus in comparison to Escherichia coli. In silico studies were conducted against enoyl-[acylcarrier-protein] reductase (FabI) and beta-lactamase enzyme to evaluate the potential of both St-g-PAA and St-g-PAA doped BaO nanocomposites as their inhibitors and to rationalize their possible mode of action.

Comparative Study of Sonophotocatalytic, Photocatalytic, and Catalytic Activities of Magnesium and Chitosan-Doped Tin Oxide Quantum Dots.

The present study demonstrates the hydrothermal synthesis of SnO2 quantum dots (QDs) doped with different concentrations (2, 4 wt %) of magnesium (Mg) and a fixed amount of chitosan (CS). The obtained samples were investigated through a number of characterizations for optical analysis, elemental composition, crystal structure, functional group presence, interlayer spacing, and surface morphology. The XRD spectrum revealed the tetragonal structure of SnO2 with no significant variations occurring upon the addition of CS and Mg. The crystallite size of QDs was reduced by incorporation of dopants. The optical absorption spectra revealed a red shift, assigned to the reduction of the band gap energy upon doping. TEM analysis proved that the few nanorod-like structures of CS overlapped with SnO2 QDs, and agglomeration was observed upon Mg doping. The incorporation of dopants little enhanced the d-spacing of SnO2 QDs. Moreover, the synthesized nanocatalyst was utilized to calculate the degradation percentage of methylene blue (MB) dye. Afterward, a comparative analysis of catalytic activity, photocatalytic activity, and sonophotocatalytic activity was carried out. Notably, 4% Mg/CS-doped QDs showed maximum sonophotocatalytic degradation of MB in basic medium compared to other activities. Lastly, the prepared nanocatalyst was found to be efficient for dye degradation in any environment and inexpensive.

Synthesis of Al/starch co-doped in CaO nanoparticles for enhanced catalytic and antimicrobial activities: experimental and DFT approaches.

In this work, aluminum/starch (St)-doped CaO nanoparticles (NPs) were synthesized by a co-precipitation method to degrade harmful dyes in various pH media. Systematic characterization was performed to investigate the influence of Al/St dopants on the composition, crystal structure, functional groups present, optical characteristics, and morphology of CaO NPs. Further hybrid density functional analyses corroborated that the band gap energy was reduced as the Al concentration in starch-doped CaO is increased. Optical absorption spectra of the synthesized materials revealed a redshift upon doping, which indicated depletion in the band gap energy of Al/St-doped CaO. PL spectroscopy showed that the intensity of CaO was reduced by the incorporation of Al and St assigned to minimum electron-hole pair recombination. Interlayer spacing and morphological features were determined by HR-TEM. HRTEM revealed that the control sample has cubic NPs and the incorporation of St showed overlapping around agglomerated NPs. The d-spacing of CaO was little enhanced by the inclusion of dopants. Experimental outcomes indicated that the addition of Co-dopants improved the catalytic potential of CaO NPs. Al (4%)/St-doped CaO NPs expressed a significant reduction of methylene blue in a basic environment. The maximum bactericidal performance was observed as 10.25 mm and 4.95 mm in the inhibition zone against S. aureus and E. coli, respectively, after the addition of Al and St in CaO.