A novel functionalized CuTi hybrid nanocomposites: facile one-pot mycosynthesis, characterization, antimicrobial, antibiofilm, antifouling and wastewater disinfection performance

BACKGROUND

The continuous progress in nanotechnology is rapid and extensive with overwhelming futuristic aspects. Through modernizing inventive synthesis protocols, a paradigm leapfrogging in novelties and findings are channeled toward fostering human health and sustaining the surrounding environment. Owing to the overpricing and jeopardy of physicochemical synthesizing approaches, the quest for ecologically adequate schemes is incontestable. By developing environmentally friendly strategies, mycosynthesis of nanocomposites has been alluring.

RESULTS

Herein, a novel architecture of binary CuO and TiO2 in nanocomposites form was fabricated using bionanofactory Candida sp., for the first time. For accentuating the structural properties of CuTi nanocomposites (CuTiNCs), various characterization techniques were employed. UV-Vis spectroscopy detected SPR at 350 nm, and XRD ascertained the crystalline nature of a hybrid system. However, absorption peaks at 8, 4.5, and 0.5 keV confirmed the presence of Cu, Ti and oxygen, respectively, in an undefined assemblage of polygonal-spheres of 15-75 nm aggregated in the fungal matrix of biomolecules as revealed by EDX, SEM and TEM. However, FTIR, ζ-potential and TGA reflected long-term stability (- 27.7 mV) of self-functionalized CuTiNCs. Interestingly, a considerable and significant biocide performance was detected at 50 µg/mL of CuTiNCs against some human and plant pathogens, compared to monometallic counterparts. Further, CuTiNCs (200 µg/mL) ceased significantly the development of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans biofilms by 80.3 ± 1.4, 68.7 ± 3.0 and 55.7 ± 3.0%, respectively. Whereas, 64.63 ± 3.5 and 89.82 ± 4.3% antimicrofouling potentiality was recorded for 100 and 200 µg/ml of CuTiNCs, respectively; highlighting their destructive effect against marine microfoulers cells and decaying of their extracellular polymeric skeleton as visualized by SEM. Moreover, CuTiNCs (100 and 200 µg/ml) exerted significantly outstanding disinfection potency within 2 h by reducing the microbial load (i.e., total plate count, mold & yeast, total coliforms and faecal Streptococcus) in domestic and agricultural effluents reached >50%.

CONCLUSION

The synergistic efficiency provided by CuNPs and TiNPs in mycofunctionalized CuTiNCs boosted its recruitment as antiphytopathogenic, antibiofilm, antimicrofouling and disinfectant agent in various realms.

Green synthesis of a magnetic hybrid adsorbent (CoFe2O4/NOM): Removal of chromium from industrial effluent and evaluation of the catalytic potential of recovered chromium ions

This work describes the removal of chromium ions from industrial effluent using a hybrid magnetic adsorbent, CoFe₂O₄/NOM, synthesized using water rich in natural organic matter. The hybrid obtained at ambient temperature (HbAmb) was calcined at 200, 400, and 800°C for 2h, and formation of the cobalt ferrite phase was confirmed by XRD, which indicated the presence of NOM in the structure of the material. Removal tests showed that HbAmb provided efficient removal of chromium at the natural pH of the effluent, while the other materials were effective at pH 6. Evaluation of the kinetics showed excellent performance of the process, with 70-87% removal in 20min, which provided a high degree of flexibility. The hybrid showed high removal during five reuse cycles, ranging from 96% in the first cycle to 82% in the final. The matrices containing the saturated adsorbent (HbAmb_Sat) and recovered chromium ions (CrD) showed high performance in the catalytic reduction of 4-nitrophenol, with conversion rates of 99.9% in short periods of time, as well as excellent potential for reuse in three cycles. The results demonstrated that the production of a technological material and its use for remediation could be achieved in an ecologically sustainable manner.

Facile preparation of Ag/Ni(OH)2 composites with enhanced catalytic activity for reduction of 4-nitrophenol

Preparation and formation mechanism of Ag/Ni(OH)₂ composites with enhanced catalytic activity for reduction of 4-nitrophenol were systematically studied.

A simple route to diverse noble metal-decorated iron oxide nanoparticles for catalysis

Developing facile synthetic routes to multifunctional nanoparticles combining the magnetic properties of iron oxides with the optical and catalytic utility of noble metal particles remains an important goal in realizing the potential of hybrid nanomaterials. To this end, we have developed a single route to noble metal-decorated magnetic nanoparticles (Fe3O4@SiO2-M; M = Au, Pd, Ag, and PtAg) and characterized them by HRTEM and STEM/EDX imaging to reveal their nanometer size (16 nm Fe3O4 and 1-5 nm M seeds) and uniformity. This represents one of the few examples of genuine multifunctional particles on the nanoscale. We show that these hybrid structures have excellent catalytic activity for the reduction of 4-nitrophenol (knorm = 2 × 10(7) s(-1) mol(Pd)(-1); 5 × 10(6) s(-1) mol(Au)(-1); 5 × 10(5) s(-1) mol(PtAg)(-1); 7 × 10(5) s(-1) mol(Ag)(-1)). These rates are the highest reported for nano-sized comparables, and are competitive with mesoparticles of similar composition. Due to their magnetic response, the particles are also suitable for magnetic recovery and maintain >99% conversion for at least four cycles. Using this synthetic route, Fe3O4@SiO2-M particles show great promise for further development as a precursor to complicated anisotropic materials or for applications ranging from nanocatalysis to biomedical sensing.

Bimetallic Ag–Cu alloy nanoparticles as a highly active catalyst for the enamination of 1,3-dicarbonyl compounds

Bimetallic Ag–Cu alloy nanoparticles were obtained via a simple co-reduction method, which exhibited significantly improved activity for the synthesis of β-enaminones and β-enaminoesters compared with their monometallic counterparts.

Versatile hierarchical Cu/Fe3O4 nanocatalysts for efficient degradation of organic dyes prepared by a facile, controllable hydrothermal method

A novel monodispersed hierarchical nanocomposite catalyst, Cu/Fe₃O₄, aimed at efficient degradation of traditional dyes, was successfully synthesized through a short-time, facile, eco-friendly hydrothermal method.

Nanosilver as a new generation of silver catalysts in organic transformations for efficient synthesis of fine chemicals

Silver nanoparticles catalysis has been of great interest in organic synthesis and has expanded rapidly in the past ten years because of nanosilver catalysts' unique reactivity and selectivity, stability, as well as recyclability in catalytic reactions.

Gold nanoparticle modified magnetic fibrous silica microspheres as a highly efficient and recyclable catalyst for the reduction of 4-nitrophenol

Au nanoparticles were immobilized on magnetic fibrous silica microspheres as highly active and recyclable nanocatalysts for the catalytic reduction of 4-nitrophenol to 4-aminophenol.

Ethylenediamine-functionalized magnetic Fe3O4@SiO2 nanoparticles: cooperative trifunctional catalysis for selective synthesis of nitroalkenes

The designed nanocatalyst Fe₃O₄@SiO₂–NH₂ was highly active for selective synthesis of nitroalkenes through cooperative trifunctional catalysis of primary amine, secondary amine and Si–OH groups.