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1.
ACS Omega ; 8(39): 35722-35737, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37810732

RESUMEN

The present study is pertinent to photo-induced, hydrophilic, nano-calcite grown onto the mercerized surface of polyester fabric (PF), treated with UV (10-50 min) and visible light (1-5 h) in addition to its photocatalytic application. The wicking method has been employed to select the most hydrophilic sample of fabric upon irradiation. The micrographs obtained by scanning electron microscopy, transmission electron microscopy, and high-resolution transmission electron microscopy indicated the erosions occurring at the surface of nano-calcite after UV light irradiation, maintaining the crystallinity of the photocatalyst. The surface charge has been measured for as-fabricated and irradiated nano-calcite @ PF for the development of high negative zeta potential after UV light irradiation (-24.6 mV). The irradiated nano-calcite @ PF exhibited a significant change in its contact angle, and the wetting property was enhanced to a considerable extent on UV (55.32°) and visible light irradiation (79.00°) in comparison to as-fabricated nano-calcite @ PF (137.54°). The irradiated samples of nano-calcite @ PF delineated the redshift in harvesting of solar spectrum, as revealed by diffuse reflectance spectroscopy comparative spectra. Additionally, the band gap of untreated nano-calcite was found to be 3.5 eV, while UV- and visible light-irradiated PF showed a reduction in band gap up to 2.95 and 3.15 eV upon UV and visible light irradiation. The photocatalytic efficiency of mesoporous nano-calcite was evaluated by photocatalytic degradation of imidacloprid as the probe pollutant. Higher solar photocatalytic degradation of imidacloprid (94.15%) was attained by UV light-irradiated nano-calcite @ PF. The time-resolved photoluminescence study has verified the high photocatalytic activity of UV light-irradiated nano-calcite @ PF for the generation of high concentration of hydroxyl radicals. The highly efficient reusability of a nano-calcite-based solar photocatalytic reactor has been observed for 10 cycles of treatment of imidacloprid bearing wastewater. The enhanced photocatalytic activity of UV light-exposed (20 min), superhydrophilic, nano-calcite @ PF for mineralization of pollutants suggests it to be an efficient solar photocatalyst for environmental applications.

2.
Environ Sci Pollut Res Int ; 30(27): 70121-70130, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37145353

RESUMEN

Nitrogenous fertilizers have low efficiency in alkaline calcareous soils due to volatilization and denitrification. These losses cause economic environmental constraints. Coating of urea with nanoparticles (NPs) is an innovative strategy to improve crop yields by sustaining N availability. In the current study, zinc oxide nanoparticles (ZnO NPs) were synthesized by precipitation method and characterized for morphology and configuration, bond formation, and crystal assemblage using the X-ray diffraction and scanning electron microscope (SEM). The SEM results confirmed the size of ZnO NPs in the size range of 25 nm with cuboid shape. Urea fertilizer, coated with ZnO NPs, was applied to wheat crop in a pot trial. Two rates of ZnO NPs at 2.8 and 5.7 mg kg-1 were selected to coat the commercial urea. A batch experiment was conducted to ensure the ammonium (NH4+) and nitrate (NO3-) ions release by amending the soil with ZnO NPs coated urea and comparing with non-amended soil. The gradual release of NH4+ was observed for 21 days from the ZnO NP-coated urea. In the second part of trial, seven different treatments of coated and uncoated urea were tested on wheat crop. Urea coated with ZnO nanoparticles at 5.7 mg kg-1 improved all growth attributes and yields. The ZnO NP coated urea increased the N content shoot (1.90 g 100g-1 DW) and potentially biofortified Zn content (47.86 mg kg-1) in wheat grain. The results are indicative of viability of a novel coating for commercial urea that will not only reduce N losses but also supplement Zn without additional cost of labor.


Asunto(s)
Nanopartículas , Óxido de Zinc , Óxido de Zinc/química , Zinc/análisis , Triticum , Suelo/química , Disponibilidad Biológica , Urea , Nitrógeno , Nanopartículas/química
4.
Curr Drug Deliv ; 20(1): 89-97, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35418284

RESUMEN

INTRODUCTION: Clarithromycin (antibiotic), due to its narrow absorption window in the gastrointestinal tract, was taken as a model drug. MATERIALS AND METHODS: Focusing on the efficient drug delivery system, floating tablets that remain buoyant over gastric fluid for 24 hrs were produced by adopting the melt mold method using beeswax, gelucire, and oleic acid. To modulate the release pattern, a different concentration of 48/16 of beeswax and gelucire was used. RESULTS: To evaluate and characterize the final product, several tests, including the percentage recovery, in-vitro release studies, clarithromycin loading, scanning electron microscopy, differential scanning calorimeter, X-ray powder diffractometry, fourier transform infrared spectroscopy, weight variation, hardness, and friability, were carried out. Regarding the results, the encapsulation efficiency of the floating tablets was 39.5% to 59%, having weight variation with and without gelucire as 48/16 0.09525±0.0032g, and 0.09527±0.00286g to 0.0957±0.00321g, respectively. Clarithromycin release was controlled by using hydrophobic beeswax and hydrophilic gelucire 48/16. X-ray powder diffractometry, differential scanning calorimeter, and fourier transform infrared spectroscopy confirmed the absence of drug-polymer interaction, and exhibited amorphous and crystalline form of the drug after encapsulation. Drug release kinetics was determined by applying different models, such as zero-order, first-order model, Higuchi, and Korsemeyer-Pappas model. All formulations followed the Korsmeyer- Peppas model at 1.2 pH. CONCLUSION: Gastroretentive drug delivery systems were produced by using melt molding technique. In vitro dissolution represents the sustained release of the drug from the formulation.


Asunto(s)
Claritromicina , Ácido Oléico , Polvos , Antibacterianos , Liberación de Fármacos , Comprimidos/química , Preparaciones de Acción Retardada/química , Solubilidad
5.
Front Chem ; 10: 805913, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35308785

RESUMEN

Chromium (VI) in tannery effluent is one of the major environmental concerns for the environmentalists due to the hazardous nature of Cr(VI) ions. To reduce Cr(VI) to Cr(III) as an innocuous moiety, pure and I-doped ZnO was grafted over the etched surface of glass beads by successive ionic layer adsorption and reaction (SILAR). Powdered, pure, and I-doped ZnO scrapped from the surface of glass beads was characterized for crystallinity, morphology, and elemental composition by XRD, SEM, TEM, and EDX. The optical properties of both photocatalysts revealed that owing to optimized iodine doping of ZnO, reduction in the bandgap was observed from 3.3 to 2.9 eV. The crystalline nano-bricks of I:ZnO adhered to glass beads were investigated to have remarkable capability to harvest sunlight in comparison to intrinsic ZnO nanodiscs. The thermal stability of I:ZnO was also found to be much improved due to doping of ZnO. The photocatalytic activities of ZnO/GB and I:ZnO/GB were compared by extent of reduction of Cr(VI) under direct natural sunlight (600-650 KWh/m2). The disappearance of absorbance peaks associated with Cr(VI) after treatment with I:ZnO/GB confirmed higher photocatalytic activity of I:ZnO/GB. The reaction parameters of solar photocatalytic reduction, i.e., initial pH (5-9), initial concentration of Cr(VI) (10-50 ppm), and solar irradiation time (1-5 h) were optimized using response surface methodology. The solar photocatalytic reduction of Cr(VI) to Cr(III) present in real tannery effluent was examined to be 87 and 98%, respectively, by employing ZnO/GB and I:ZnO/GB as solar photocatalysts. The extent of reduction was also confirmed by complexation of Cr(VI) and Cr(III) present in treated and untreated tannery waste with 1, 5-diphenylcarbazide. The results of AAS and UV/vis spectroscopy for the decrease in concentration of Cr also supported the evidence of higher efficiency of I:ZnO/GB for reduction of Cr(VI) in tannery effluent. Reusability of the fabricated photocatalyst was assessed for eight cycles, and magnificent extent of reduction of Cr(VI) indicated its high efficiency. Conclusively, I:ZnO/GB is a potential and cost-effective candidate for Cr(VI) reduction in tannery effluent under natural sunlight.

6.
Polymers (Basel) ; 14(2)2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35054700

RESUMEN

To eliminate imidacloprid insecticide from wastewater, nanocalcite was grafted onto the surface of pretreated polyester fabric. The process of seeding was followed by the low temperature hydrothermal method for the growth of nanocalcite for the functionalization of fabric. The goal of this study was to improve the hydrophilicity of the nanocalcite photocatalyst that had been grafted onto the surface of polyester fabric (PF) using acidic and basic prewetting techniques. The morphological characteristics, crystalline nature, surface charge density, functional groups of surface-modified nanocalcite @ PF were determined via SEM, XRD, FTIR, and Zeta potential (ZP), respectively. Characterization results critically disclosed surface roughness due to excessive induction of hydroxyl groups, rhombohedral crystal structure, and high charge density (0.721 mS/cm). Moreover, contact angle of nanocalcite @ PF was calculated to be 137.54° while after acidic and basic prewetting, it was reduced to 87.17° and 48.19°. Similarly, bandgap of the as fabricated nanocalcite was found to be 3.5 eV, while basic prewetted PF showed a reduction in band gap (2.9 eV). The solar photocatalytic mineralization of imidacloprid as a probe pollutant was used to assess the improvement in photocatalytic activity of nanocalcite @ PF after prewetting. Response surface methodology was used to statistically optimize the solar exposure time, concentration of the oxidant, and initial pH of the reaction mixture. Maximum solar photocatalytic degradation of the imidacloprid was achieved by basic prewetted nanocalcite @ PF (up to 91.49%), which was superior to acidic prewetted fabric and as-fabricated nanocalcite @ PF. Furthermore, HPLC and FTIR findings further indicated that imidacloprid was decomposed vastly to harmless species by basic prewetted nanocalcite @ PF.

7.
Polymers (Basel) ; 13(22)2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34833342

RESUMEN

Among chemical water pollutants, Cr(VI) is a highly toxic heavy metal; solar photocatalysis is a cost-effective method to reduce Cr(VI) to innocuous Cr(III). In this research work, an efficient and economically feasible ZnO/CuO nanocomposite was grafted onto the polyester fabric ZnO/CuO/PF through the SILAR method. Characterization by SEM, EDX, XRD, and DRS confirmed the successful grafting of highly crystalline, solar active nanoflakes of ZnO/CuO nanocomposite onto the polyester fabric. The grafting of the ZnO/CuO nanocomposite was confirmed by FTIR analysis of the ZnO/CuO/PF membrane. A solar photocatalytic reduction reaction of Cr(VI) was carried out by ZnO/CuO/PF under natural sunlight (solar flux 5-6 kW h/m2). The response surface methodology was employed to determine the interactive effect of three reaction variables: initial concentration of Cr(VI), pH, and solar irradiation time. According to UV/Vis spectrophotometry, 97% of chromium was removed from wastewater in acidic conditions after four hours of sunlight irradiation. ZnO/CuO/PF demonstrated reusability for 11 batches of wastewater under natural sunlight. Evaluation of Cr(VI) reduction was also executed by complexation of Cr(VI) and Cr(III) with 1, 5-diphenylcarbazide. The total percentage removal of Cr after solar photocatalysis was carried out by AAS of the wastewater sample. The ZnO/CuO/PF enhanced the reduction of Cr(VI) metal from wastewater remarkably.

8.
Int J Mol Sci ; 22(14)2021 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-34299082

RESUMEN

The Mimosa genus belongs to the Fabaceae family of legumes and consists of about 400 species distributed all over the world. The growth forms of plants belonging to the Mimosa genus range from herbs to trees. Several species of this genus play important roles in folk medicine. In this review, we aimed to present the current knowledge of the ethnogeographical distribution, ethnotraditional uses, nutritional values, pharmaceutical potential, and toxicity of the genus Mimosa to facilitate the exploitation of its therapeutic potential for the treatment of human ailments. The present paper consists of a systematic overview of the scientific literature relating to the genus Mimosa published between 1931 and 2020, which was achieved by consulting various databases (Science Direct, Francis and Taylor, Scopus, Google Scholar, PubMed, SciELO, Web of Science, SciFinder, Wiley, Springer, Google, The Plant Database). More than 160 research articles were included in this review regarding the Mimosa genus. Mimosa species are nutritionally very important and several species are used as feed for different varieties of chickens. Studies regarding their biological potential have shown that species of the Mimosa genus have promising pharmacological properties, including antimicrobial, antioxidant, anticancer, antidiabetic, wound-healing, hypolipidemic, anti-inflammatory, hepatoprotective, antinociceptive, antiepileptic, neuropharmacological, toxicological, antiallergic, antihyperurisemic, larvicidal, antiparasitic, molluscicidal, antimutagenic, genotoxic, teratogenic, antispasmolytic, antiviral, and antivenom activities. The findings regarding the genus Mimosa suggest that this genus could be the future of the medicinal industry for the treatment of various diseases, although in the future more research should be carried out to explore its ethnopharmacological, toxicological, and nutritional attributes.


Asunto(s)
Etnofarmacología , Mimosa/química , Fitoquímicos/farmacología , Fitoterapia/métodos , Extractos Vegetales/farmacología , Humanos
9.
Nanotechnology ; 32(48)2021 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-34320471

RESUMEN

The COVID-19 outbreak is creating severe impressions on all facets of the global community. Despite strong measures worldwide to try and re-achieve normalcy, the ability of SARS-CoV-2 to survive sturdy ecological settings may contribute to its rapid spread. Scientists from different aspects of life are working together to develop effective treatment strategies against SARS-CoV-2. Apart from using clinical devices for patient recovery, the key focus is on developing antiviral drugs and vaccines. Given the physical size of the SARS-CoV-2 pathogen and with the vaccine delivery platform currently undergoing clinical trials, the link between nanotechnology is clear, and previous antiviral research using nanomaterials confirms this link. Nanotechnology based products can effectively suppress various pathogens, including viruses, regardless of drug resistance, biological structure, or physiology. Thus, nanotechnology is opening up new dimensions for developing new strategies for diagnosing, preventing, treating COVID-19 and other viral ailments. This article describes the application of nanotechnology against the COVID-19 virus in terms of therapeutic purposes and vaccine development through the invention of nanomaterial based substances such as sanitizers (handwashing agents and surface disinfectants), masks and gowns, amongst other personal protective equipment, diagnostic tools, and nanocarrier systems, as well as the drawbacks and challenges of nanotechnology that need to be addressed.


Asunto(s)
Antivirales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Vacunas contra la COVID-19/uso terapéutico , Sistemas de Liberación de Medicamentos , Nanoestructuras/uso terapéutico , Pandemias/prevención & control , SARS-CoV-2/metabolismo , Animales , COVID-19/epidemiología , COVID-19/metabolismo , COVID-19/terapia , Humanos , Nanotecnología
10.
Toxicol Ind Health ; 34(11): 753-763, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30227779

RESUMEN

Zinc oxide nanoparticles (ZnONPs) are being used extensively in manufacturing skin lotions and food products and in various biological and pharmaceutical industries because of their immunomodulatory and antimicrobial properties. In this study, ZnONPs were synthesized by a precipitation method and characterized by X-ray diffraction (XRD) techniques, scanning electron microscopy (SEM), and ultraviolet-visible spectroscopy to investigate their structural, morphological, and optical properties. For in vivo evaluation, 40 healthy albino mice were randomly allocated to four equal groups among which the first one was the control group, while the second, third, and fourth were treated with carbon tetrachloride (CCl4), a blend of CCl4 and ZnONPs, and ZnONPs alone, respectively, for 21 days. The XRD analysis confirmed hexagonal wurtzite type structures having an average crystallite size of 41.54 nm. The morphology of ZnONPs analyzed through SEM showed uniform distribution of the grains and shape of the synthesized oxide. The energy band gap of the ZnONPs was found to be 3.498 eV. Hepatic and renal damage following CCl4 administration was apparent after 14 days and was increased at the 21st day, showing nodular fibrotic masses in the liver and bumpy surfaces in the kidney as observed by gross and histological examination. Coadministration of ZnONPs (15 mg/kg b.w. intragastrically 5 days a week) significantly prevented the CCl4-dependent increases in alanine transaminase, aspartate transaminase, creatinine, and urea levels, suggesting a protective potential of ZnONPs.


Asunto(s)
Nanopartículas del Metal , Óxido de Zinc , Animales , Tetracloruro de Carbono , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Femenino , Riñón/efectos de los fármacos , Riñón/patología , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Ratones , Óxido de Zinc/síntesis química , Óxido de Zinc/química , Óxido de Zinc/toxicidad
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