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1.
Microb Pathog ; 127: 144-158, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30502518

RESUMEN

This study reports the photocatalytic degradation of Methylene Blue (MB) dye (a class of dyestuffs that are resistant to biodegradation) under the influence of UV-light irradiation. Antibacterial and antibiofilm activities of ferrite nanoparticles (FO NPs) were examined against some pathogenic bacteria isolated from the medical operating room surfaces. In the same context, metals-substituted spinel cobalt ferrite nanoparticles with nominal composition [MxCo1-xFe2O4 NPs; (M = Zn, Cu, Mn; x = 0.0, 0.25, 0.5 and 0.75)] were synthesized by citrate sol-gel method. Also, the structures of the synthesized FO NPs were characterized by X-ray diffraction, and Williamson-Hall (WH) method was used to determine the crystallite size. The estimated specific surface area is found in the range from 37.99 to 107.05 m2/g, between the synthesized ferrites, Zn0.5Co0.5Fe2O4 NPs have average pore radius 1.84 nm and the pore volume was 0.136 ml/g. SEM images revealed that, the synthesized FO NPs have an unique pores and uniformly distribution, while EDX spectra shows the elemental composition for the synthesized FO NPs. The elastic properties of FO NPs have been estimated using FTIR data, whereas (M - H) hysteresis loops revealed that, by replacing cobalt ions with Zn, Cu, and Mn ions the magnetic behaviour changed from ferromagnetic to paramagnetic. Results obtained from the photocatalysis indicated that Mn0.75Co0.25Fe2O4 NPs (30.0 mg) were a promising photocatalyst achieving 96.0% removal of MB after 100 min of UV-light exposure in the alkaline solution. Antibacterial results showed that the most effective combination was Zn0.75Co0.25Fe2O4 NPs (20.0 ppm) displaying activity against Staphylococcus aureus, Enterococcus columbae, and Aerococcus viridians by 15.0, 13.0, and 12.0 mm ZOI, respectively. Additionally, Zn0.75Co0.25Fe2O4 NPs were active as antibiofilm factors producing activity by 63.7, 57.9, and 45.5% towards S. aureus, A. viridians, and E. columbae, respectively. Accordingly, Zn0.75Co0.25Fe2O4 and Mn0.75Co0.25Fe2O4 NPs can be utilized in industrial, biological and medical applications.


Asunto(s)
Óxido de Aluminio/farmacología , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Cobalto/farmacología , Compuestos Férricos/farmacología , Bacterias Grampositivas/efectos de los fármacos , Óxido de Magnesio/farmacología , Metales/farmacología , Nanopartículas/química , Óxido de Aluminio/síntesis química , Antibacterianos/síntesis química , Antibacterianos/química , Biopelículas/crecimiento & desarrollo , Pruebas Antimicrobianas de Difusión por Disco , Bacterias Grampositivas/crecimiento & desarrollo , Óxido de Magnesio/síntesis química , Azul de Metileno/metabolismo , Análisis Espectral , Difracción de Rayos X
2.
Mater Sci Eng C Mater Biol Appl ; 92: 644-656, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30184791

RESUMEN

Nanocrystalline spinel ferrite nanoparticles [MxCo(1-x)Fe2O4;(M = Zn,Cu,Mn;x = 0 and 0.5)] like: Cobalt ferrite (CFO), Zinc Cobalt ferrite (ZCFO), Copper Cobalt ferrite (CCFO), and Manganese Cobalt ferrite (MCFO) modified carbon paste electrodes (CPE) were synthesized via sol-gel technique utilizing citric acid and ethylene glycol as a polymerization agent. The synthesized ferrite NPs were used as bi-functional smart biosensor, not only used to determine the drug Anagrelide-HCl (ANDH) in urine and serum samples, but also possesses antimicrobial potential against some pathogenic microbes, founded in the biological samples. The synthesized ferrite NPs were confirmed by XRD, FTIR spectroscopy, SEM, EDX, and elemental mapping images. Antimicrobial activities of ferrite NPs against selected urinary tract infected microbes were investigated. From XRD data and FTIR spectroscopy it is found that the average crystallite size is lies in the range 12.86 to 33.92 ±â€¯1.5 nm, also the bond lengths RA and RB increase from 1.8986 to 1.9145 Šand from 2.0434 to 2.0606 Šrespectively and Debye temperature θD lies in the range of 681.52-708.87 K. Our study describes the improvement of a screen-printed sensor, modified with ferrite NPs materials for rapid, sensitive and cost-effective quantification of ANDH present in the real samples such as blood serum samples, urine and in the pharmaceutical formulations. The results obtained postulate a linear regression between the ANDH charge density of peak current and its concentration in the range from (0.64-8.18 µg/ml) with DL 0.31 µg/ml and QL 0.94 µg/ml. Antimicrobial results indicated that ZCFO NPs were a novel antibacterial agent against Klebsiella pneumoniae (28.0 mm ZOI), and multidrug-resistant bacteria Enterococcus faecalis (27.0 mm ZOI). Additionally, ZCFO NPs were active against Candida albicans (18.0 mm ZOI) seems to be a smart antifungal agent. Therefore, ZCFO NPs can be used as applicant resources for industrial, medical, and biological applications.


Asunto(s)
Antiinfecciosos , Candida albicans/crecimiento & desarrollo , Cobalto , Enterococcus faecalis/crecimiento & desarrollo , Compuestos Férricos , Klebsiella pneumoniae/crecimiento & desarrollo , Nanopartículas/química , Quinazolinas/análisis , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Cobalto/química , Cobalto/farmacología , Compuestos Férricos/síntesis química , Compuestos Férricos/química , Compuestos Férricos/farmacología
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