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1.
Environ Res ; 221: 115213, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36610540

RESUMO

A special type of two-dimensional (2D) material based conducting polymer was constructed by green synthesis and in-situ polymerization techniques. The 2D Molybdenum Disulfide (MoS2) were first synthesized with the combination of, ammonium tetrathiomolybdate dissolved in 20 mL algae extract under stirring. After stirring for about 2 h, and then finally sulfurization was initiated using sulfur powder in 20 mL of sulfuric solution and stirred for 8 h. The resulting black precipitates of MoS2 were collected by centrifugation at 5000 rpm. Moreover, the prepared MoS2 was functionalized with glycidyl methacrylate (GMA) and form the MoS2@PGMA. Further, the MoS2@PGMA is combined with polyaniline (PANI) to form conducting polymer grafted thin film nanosheets named MoS2@PGMA/PANI with a thickness in micrometer size through grafting method. The prepared materials were characterized by SEM, FTIR, XRD, XPS and EDX techniques. To check the performance of materials the adsorption study was performed. Moreover, the adsorption study toward Cu2+ and Cd2+ showed a tremendous results and the maximum adsorption was 307.7 mg/g and 214.7 mg/g respectively. In addition, the pseudo-first and second order models as well as the adsorption isotherm were investigated using the Langmuir and Freundlich model. The results were best fitted with the pseudo-second order and Langmuir models. The regeneration study was also conducted and MoS2@PGMA/PANI nanosheets can be easily recycled and restored after five successful recycling. The established methodology for preparing the 2D materials and conducting polymer based MoS2@PGMA/PANI nanosheets is expected to be applicable for other multiple applications.


Assuntos
Molibdênio , Águas Residuárias , Metais , Polímeros , Íons
2.
Pak J Pharm Sci ; 31(1): 181-186, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29348101

RESUMO

The aim of the present study was to examine the effect of gamma radiation on levofloxacin. Powder form of levofloxacin was subjected to different radiation doses (25, 50, 75, 100 and 125kGy) of Cobalt-60 source in a Gammacell-220 at a rate of 8.5 Gray/hr. The effect of radiation has been investigated with the aid of different spectroscopic techniques (UV-Vis, FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and by antibacterial activities. UV data did not reveal significant changes in the structure of levofloxacin which is supported by scanning electron microscopy. However, X-rays diffraction shows a change in crystallinity of levofloxacin to an amorphous structure and this has been reflected on the morphology of this compound as indicated by SEM images. The antibacterial activities, on the other hand, reveal resistance of irradiated levofloxacin against bacteria, where some bacteria were highly affected by the irradiated drug. Similarly, FT-IR data show some changes in the functional groups principal absorption bands, in the IR spectrum, at frequencies 3286, 2846, 1716 and 1620 cm-1 for the O-H stretching band of quinolone, C-H stretching band, and C=O stretching band of carboxylic and pyridine. In addition, new peaks appeared which were not seen in the non-irradiated spectrum. In conclusion, some changes occurred in levofloxacin drug with the passage of radiation but the drug was chemically stable.


Assuntos
Antibacterianos/efeitos da radiação , Raios gama , Levofloxacino/efeitos da radiação , Esterilização/métodos , Antibacterianos/química , Bactérias Gram-Negativas/efeitos da radiação , Bactérias Gram-Positivas/efeitos da radiação , Levofloxacino/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pós , Estereoisomerismo , Propriedades de Superfície
3.
Microb Pathog ; 99: 271-281, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27591110

RESUMO

New strategies are required to improve the efficacy of drugs and to treat the emerging microbial resistance. An effective strategy is to combine drugs with metal nanoparticles for the control of microbial infections and resistance. Keeping in view this fact, we developed a facile and eco-friendly protocol for the synthesis of amphotericin B-conjugated silver nanoparticles and their assessment as an antifungal agent. Phytochemicals from the aqueous extract of Maytenus royleanus and amphotericin B were used as capping agents to prepare two types of silver nanoparticles i.e. (i) biogenic silver nanoparticles (b-AgNPs) and (ii) amphotericin B-conjugated biogenic silver nanoparticles (Amp-bAgNPs). UV-Vis spectroscopy was used to detect the characteristic surface Plasmon resonance peaks (SPR) for the prepared nanoparticles (424-433 nm). High-resolution transmission electron microscopy (HRTEM) study revealed the formation of well dispersed and spherical silver nanoparticles and Amp-bAgNPs with an average particles size of 10 and 15 nm. EDX and FTIR studies confirmed the elemental composition and surface adhered biomolecules in the prepared nanoparticles respectively. Biogenic silver nanoparticles revealed low to moderate antifungal activity (4-8 mm ± 0.2), however, the amphotericin B conjugated silver nanoparticles exhibited significant activity against Candida albicans (16 mm ± 1.4) and Candida tropicalis (18 mm ± 1.5). In conclusion, the enhanced antifungal activity of the Amp-AgNPs conjugate system is due to the synergy between the antifungal activity of amphotericin B and the antimicrobial property of silver. The findings of this study suggest that the conjugated nanoparticles could be used as efficient antifungal agents and drug delivery vehicles. Furthermore, this is the first report describing the synthesis of silver nanoparticles using the aqueous extract of Maytenus royleanus and the conjugation of amphotericin B, an antifungal drug, to the phytosynthesized silver nanoparticles.


Assuntos
Anfotericina B/metabolismo , Antifúngicos/metabolismo , Nanopartículas/metabolismo , Prata/metabolismo , Candida albicans/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Sinergismo Farmacológico , Maytenus/química , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Micoses , Nanopartículas/química , Nanopartículas/ultraestrutura , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Espectrometria por Raios X , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier , Ressonância de Plasmônio de Superfície
4.
Microsc Res Tech ; 87(6): 1286-1305, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38351883

RESUMO

Diabetes is a life-threatening disease that affects different parts of the body including the liver, kidney, and pancreas. The core root of diabetes is mainly linked to oxidative stress produced by reactive oxygen species (ROS). Berberis lyceum Royle (BLR) is the source of natural products. It comprises numerous bioactive compounds having antioxidant activities. In the current investigation, silver nanoparticles from BLR root extract were synthesized, characterized, and assessed for antidiabetic potential. UV spectrophotometry, Transmission electron microscopy (TEM), Fourier transform infra-red spectroscopy (FTIR), and x-ray diffraction (XRD) were applied for the characterization of NPs. It was evident from the morphological studies that the synthesized NPs were spherical and the average size was 11.02 nm. Results revealed that BLR-AgNPs showed higher radical scavenging activity as compared to BLR extract. Moreover, BLR-AgNPs displayed superior in vivo and in vitro antidiabetic activity in comparison to BLR extract. Glucose level (116.5 ± 5.1 mg/dL), liver function test (ALAT: 54.038 ± 6.2 IU/L; ASAT: 104.42 ± 13.9 IU/L; ALP: 192.6 ± 2.4 IU/L; bilirubin: 1.434 ± 0.14 mg/dL; total protein: 5.14 ± 0.24 mg/dL), renal function test (urea: 39.6 ± 0.63 mg/dL; uric acid: 21.4 ± 0.94 mg/dL; creatinine: 0.798 ± 0.03 mg/dL; albumin: 4.14 ± 0.2 mg/dL), lipid profile level (cholesterol: 101.62 ± 3 mg/dL; triglyceride: 110.42 ± 7 mg/dL; HDL-C: 29.7 ± 3 mg/dL; LDL-C: 47.056 ± 1 mg/dL; VLDL-C: 22.0 ± 1.3 mg/dL) and hematology (WBCs: 3.82 ± 0.24 103 /µL; RBCs: 4.78 ± 0.42 106 /µL; Hb: 12.6 ± 1.0 g/dL; Hematocrit: 39.4 ± 3.7%; MCV: 65.8 ± 3 fL; platelets: 312 ± 22.4; neutrophils: 34.8 ± 1.87; eosinophils: 3.08 ± 0.43; monocytes: 3.08 ± 0.28; lymphocytes: 75.6 ± 3.77) confirmed the significant antidiabetic potential of BLR-AgNPs. Histopathological examination authenticated that BLR-AgNPs caused a significant revival in the morphology of the liver, kidney, and pancreas. Hence, findings of the study suggested the BLR-AgNPs as a potent antidiabetic agent and could be an appropriate nanomedicine to prevent diabetes in future. RESEARCH HIGHLIGHTS: Berberis lyceum extract as a reducing, capping, and stabilization agent for the BLR-AgNPs synthesis Evaluation of α-amylase inhibition, antioxidant, and α-glucosidase inhibition potential Thorough characterization using Fourier transform infrared spectroscopy, Transmission electron microscopy, x-ray diffraction, and UV-VIS spectrophotometer, which is 1st of its kind In-vivo antidiabetic activity evaluation through multiple biomarkers.


Assuntos
Berberis , Diabetes Mellitus , Nanopartículas Metálicas , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Prata/farmacologia , Difração de Raios X , Antioxidantes/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas Metálicas/química , Extratos Vegetais/química , Microscopia Eletrônica de Transmissão , Antibacterianos/farmacologia
5.
Int J Biol Macromol ; 253(Pt 4): 126986, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37739285

RESUMO

The presence of pollutants in drinking water has become a significant concern recently. Various substances, including activated carbon, membranes, biochar, etc., are used to remove these pollutants. In the present study, a new composite comprising cotton fabric and a mixture of Metal-Organic Frameworks (MOFs) was synthesized and used as an adsorbent for eliminating pollutants from wastewater. At first, the UiO-66 MOFs were prepared by a simple method of reacting Zirconium (IV) chloride (ZrCl4) and p-Phthalic acid (PTA) after successful preparation of UiO-66 then modified its surface with amino functional groups by reacting with APTES to obtain UiO-66-NH2. Moreover, the cellulose cotton fabric (CF) surface was modified with Polydopamine (PDA) and obtained CF@PDA. Further, with the help of EDC-HCl and NHS, the UiO-66-NH2 grafted on the surface of the CF@PDA and finally obtained CF@PDA/UiO-66-NH2. In addition, the adsorption study was performed toward RhB dye and Pb(II) metal ion pollutants. The maximum adsorption toward RhB dye was 68.5 mg/g, while toward Pb(II) metal ions was 65 mg/g. In addition, the kinetic study was also conducted and the result favoured the Pseudo-second order kinetic study. The adsorption isotherm was also studied and the Langmuir model was more fitted as compared with the Freundlich model. Moreover, the material has excellent regeneration and recycling ability after ten cycles. The significant adsorption ability, the novel combination of cotton and MOFs, and the recycling feature make our material CF@PDA/UiO-66-NH2 a promising potential absorbent material for wastewater treatment and even in other important areas of water research.


Assuntos
Poluentes Ambientais , Estruturas Metalorgânicas , Compostos Organometálicos , Poluentes Químicos da Água , Águas Residuárias , Chumbo , Celulose , Íons , Adsorção
6.
J Hazard Mater ; 366: 723-731, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30597388

RESUMO

A high performance thermally expanded reduced graphene oxide (TErGO) nanocomposite decorated with Ni3C-Ni nanoparticles (TErGO/Ni3C-Ni) has been successfully synthesized by using a facile and eco-friendly approach. The morphology, textural features, surface composition and stability of TErGO/Ni3C-Ni nanocomposite are investigated by various physicochemical characterizations which revealed the uniform dispersion of crystalline metal nanoparticles inside TErGO matrix. The composite has been exhibited a large surface area and pore volume of 121 m2 g-1 and 0.791 cm3 g-1, respectively. The TErGO/Ni3C-Ni exhibited remarkable catalytic performance surpassing most metal-based catalysts with various kind of support matrices reported in recent literature. The reduction of Cr(Ⅵ) to Cr(Ⅲ) was achieved within 1 min with an excellent rate constant of 2.74 min-1 and phenomenally higher specific removal rate (SRR) of 0.29 mg Cr(VI) min-1. mg-1 of TErGO/Ni3C-Ni. While it also proved an excellent reducing catalyst for organic dyes via NaBH4 with full reduction achieved within 30 s. Moreover, as prepared nanocatalyst possesses excellent stability and recyclability with easy magnetic separation.

7.
J Photochem Photobiol B ; 164: 164-173, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27689741

RESUMO

There is a growing need to introduce eco-friendly and sustainable procedures for the synthesis of metal nanoparticles that include a mild reaction conditions, simple reaction setup, use of nontoxic medium such as water and plant extract, cost effectiveness as well as greater efficiency for biomedical and catalytic applications. For this purpose, small and highly dispersed palladium nanoparticles (PdNPs) were prepared by eco-friendly and cost effective green method using water soluble leaf extract of Sapium sebiferum as a reducing and capping agent. The formation of PdNPs was optimized at various temperatures i.e. (30°C, 60°C and 90°C) and different leaves extract (5mL and 10mL) in order to control their size and shape. The results indicated that PdNPs synthesized at 10mL leaf extract concentration and 60°C temperature have small sized (5nm) and spherical shape. The nanoparticles formation, their dispersion, size and shape were confirmed by various characterization techniques i.e. UV-Vis spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), thermo gravimetric analysis (TGA) and Dynamic light scattering technique (DLS) analysis. The biologically synthesized PdNPs were tested for size dependent photo degradation of methylene blue and inactivation of bacteria. The PdNPs synthesized at optimized condition (10mL extract concentration and 60°C) have strong photo catalytic activity and reduced 90% methylene blue in 70min. The optimized PdNPs also showed strong bacterial inhibition against Staphylococcus aureus 29(±0.8mm), Bacillus subtilis 19(±0.6mm) and pseudomonas aeruginosa 11(±0.6mm). The results of this examination demonstrate effective applications of extremely active PdNPs.


Assuntos
Bactérias/efeitos dos fármacos , Nanopartículas Metálicas/química , Paládio/química , Folhas de Planta/química , Sapium/química , Catálise , Técnicas In Vitro , Nanopartículas Metálicas/toxicidade , Fotoquímica
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