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1.
ACS Omega ; 8(45): 42479-42491, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38024753

RESUMO

In this study, an eco-friendly strategy was used to prepare a novel SrTiO3/Ag/rGO composite. A SrTiO3/Ag/rGO composite-modified screen-printed carbon electrode (SPCE) was applied for the electrochemical detection of 4-nitrophenol. A simple ultrasonic method with an ultrasonic frequency of 20 kHz was used for the synthesis of SrTiO3/Ag/rGO composite material. The obtained SrTiO3/Ag/rGO composite was characterized by X-ray diffraction, Fourier transform infrared, Raman spectroscopy, field emission electron microscopy, and UV-visible spectroscopy. Electrochemical impedance spectroscopy was used to determine the electrical conductivity of the SrTiO3/Ag/rGO composite. The electrochemical properties of the modified electrode were studied using cyclic voltammetry as well as linear sweep voltammetry techniques. In comparison to SrTiO3/SPCE, SrTiO3/Ag/SPCE, and SrTiO3/rGO/SPCE electrodes, SrTiO3/Ag/rGO/SPCE demonstrates a considerable increase in 4-nitrophenol redox peak current. At optimum conditions, a large linear response range of 0.1-1000 M, with a relatively low limit of detection (0.03 M), outperforms the previously published modified electrode for 4-nitrophenol. Moreover, the SrTiO3/Ag/rGO/SPCE electrode-based 4-nitrophenol sensor is distinguished by good selectivity, high stability, and repeatability. Furthermore, SrTiO3/Ag/rGO/SPCE contributed to the detection of 4-nitrophenol in river water and drinking water with the recovery range from 97.5 to 98.7%. The experimental finding was supported by density functional theory calculation.

2.
J Photochem Photobiol B ; 183: 251-257, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29734113

RESUMO

In modern era, the great interest and demand among chemists and researchers for metal nanoparticles is increasing in the application of biomedical fields, textiles, cosmetics and various sectors. Consequently, the present study reports an eco-friendly, cost-effective, rapid and easy method to produce environment-friendly metal nanoparticles to prevent exhaustion of metal resources. In this context, gold and silver metal nanoparticles were green synthesized using the Root Extract of Coleous forskohlii (RECo) as capping and reducing agent. The synthesized gold (GNPs) and silver nanoparticles (SNPs) were characterized using UV-Visible spectrophotometer, High-resolution transmission electron microscopy (HR-TEM), Particle size analysis (PSA), Fourier-transform infrared spectroscopy (FT-IR) and X-Ray Diffractometer (XRD). Their clinical importance was analysed using anti-oxidant assay (DPPH - 2,2-diphenyl-1-picrylhydrazyl and Phosphomolybdenum PMA) and cytotoxicity (MTT assay) against HEPG2 (liver cancer cell lines). Further, the antimicrobial activity against two microorganisms were tested using disc diffusion method against Proteus vulgaris pathogen and Micrococcus luteus pathogen. RECo-GNPs and SNPs were found to be stable in aqueous medium for a longer time and exhibited favorable anti-oxidant, anti-bacterial and anti-cancer activity. The phytoconstituents present in the root extract of Coleous forskohlii was elucidated using GC-MS analysis.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Ouro/química , Nanopartículas Metálicas/química , Plectranthus/química , Prata/química , Anti-Infecciosos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Química Verde , Células Hep G2 , Humanos , Nanopartículas Metálicas/toxicidade , Micrococcus luteus/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Extratos Vegetais/química , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Plectranthus/metabolismo , Proteus vulgaris/efeitos dos fármacos , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
3.
Biomed Tech (Berl) ; 63(3): 245-253, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28678733

RESUMO

Electrospun polyurethane based nanocomposite scaffolds were fabricated by mixing with indhulekha oil. Scanning electron microscope (SEM) portrayed the nanofibrous nature of the composite and the average diameters of the composite scaffold were smaller than the pristine scaffolds. The fabricated scaffold was found to be hydrophobic (114°) due to the inclusion of indhulekha oil, which was displayed in contact angle measurement analysis. The fourier transform infrared spectroscopy (FTIR) results indicated that the indhulekha oil was dispersed in PU matrix identified by formation of hydrogen bond and peak shifting of CH group. The PU/indhulekha oil nanocomposite exhibits a higher decomposition onset temperature and also residual weight percentage at 900°C was more compared to the pure PU. Surface roughness was found to be increased in the composite compared to the pristine PU as indicated by the atomic force microscopy (AFM) analysis. In order to investigate the blood compatibility of electrospun nanocomposites the activated partial thromboplastin time (APTT) assay, prothrombin time (PT) assay and hemolytic assay were performed. The blood compatibility results APTT and PT revealed that the developed nanocomposites demonstrated delayed clotting time indicating the anticoagulant nature of the composite in comparison with the pristine PU. Further, it was also observed that the hemolytic index of nanocomposites was reduced compared to pure PU suggesting the non-hemolytic nature of the fabricated scaffold. Hence, the fabricated nanocomposites might be considered as a potent substitute for scaffolding damaged tissue due to their inherent physicochemical and blood compatibility properties.


Assuntos
Materiais Biocompatíveis/química , Óleos/química , Poliuretanos/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Interações Hidrofóbicas e Hidrofílicas , Nanocompostos , Espectroscopia de Infravermelho com Transformada de Fourier
4.
J Cancer Res Ther ; 13(6): 916-929, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29237952

RESUMO

Cancer-related fatigue is a symptom of cancer where most patients or the general practitioners tend to misinterpret due to the insufficient understanding or knowledge of cancer-related fatigue (CRF). This paper will provide a better perspective for the patients and the health professionals on how to manage and handle CRF for both mild and severe fatigue patients. Articles were selected from the searches of PubMed database that had the terms "randomized controlled trials," "cancer," "fatigue," "pharmacologic treatment," and "nonpharmacologic treatment" using both Mesh terms and keywords. The authors have reviewed the current hypothesis and evidence of the detailed etiology of the CRF present in the literature for healthier management, directives, and strategies to improve the treatment of cancer-related fatigue. An algorithm has been blueprinted on screening, and management, of the CRF, and various kinds of effective treatments and assessment tools have been briefly studied and explained. Although many strategies seemed promising, the quality of randomized controlled trials is generally quite low in studies, making it difficult to draw conclusions about the effectiveness of each self-care strategies. Therefore, future studies require better design and reporting of methodological issues to ensure evidence-based self-care recommendations for people receiving cancer treatment.


Assuntos
Fadiga/terapia , Neoplasias/tratamento farmacológico , Fadiga/induzido quimicamente , Fadiga/patologia , Humanos , Neoplasias/complicações , Neoplasias/patologia , Qualidade de Vida , Resultado do Tratamento
5.
An Acad Bras Cienc ; 89(3 Suppl): 2411-2422, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29091109

RESUMO

In this work, the physicochemical and blood compatibility properties of prepared PU/Bio oil nanocomposites were investigated. Scanning electron microscope (SEM) studies revealed the reduction of mean fiber diameter (709 ± 211 nm) compared to the pristine PU (969 nm ± 217 nm). Fourier transform infrared spectroscopy (FTIR) analysis exposed the characteristic peaks of pristine PU. Composite peak intensities were decreased insinuating the interaction of the bio oilTM with the PU. Contact angle analysis portrayed the hydrophobic nature of the fabricated patch compared to pristine PU. Thermal gravimetric analysis (TGA) depicted the better thermal stability of the novel nanocomposite patch and its different thermal behavior in contrast with the pristine PU. Atomic force microscopy (AFM) analysis revealed the increase in the surface roughness of the composite patch. Activated partial thromboplastin time (APTT) and prothrombin time (PT) signified the novel nanocomposite patch ability in reducing the thrombogenicity and promoting the anticoagulant nature. Finally the hemolytic percentage of the fabricated composite was in the acceptable range revealing its safety and compatibility with the red blood cells. To reinstate, the fabricated patch renders promising physicochemical and blood compatible nature making it a new putative candidate for wound healing application.


Assuntos
Teste de Materiais , Membranas Artificiais , Nanocompostos/ultraestrutura , Poliuretanos/química , Humanos , Microscopia Eletrônica de Varredura , Nanocompostos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
6.
3 Biotech ; 7(3): 174, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28660462

RESUMO

Atrial septal defect (ASD) constitutes 30-40% of all congenital heart diseases in adults. The most common complications in the treatment of ASD are embolization of the device and thrombosis formation. In this research, an occluding patch was developed for ASD treatment using a well-known textile technology called electrospinning. For the first time, a cardiovascular occluding patch was fabricated using medical grade polyurethane (PU) loaded with bioactive agents namely chitosan nanoparticles (Cn) and collagen (Co) which is then coated with heparin (Hp). Fourier transform infrared spectrum showed characteristic vibrations of several active constituents and changes in the absorbance due to the inclusion of active ingredients in the patch. The contact angle analysis demonstrated no significant decrease in contact angle compared to the control and the composite patches. The structure of the electrospun nanocomposite (PUCnCoHp) was examined through scanning electron microscopy. A decrease in nanofiber diameter between control PU and PUCnCoHp nanocomposite was observed. Water uptake was found to be decreased for the PUCnCoHp nanocomposite against the control. The hemocompatibility properties of the PUCnCoHp ASD occluding patch was inferred through in vitro hemocompatibility tests like activated partial thromboplastin time (APTT), prothrombin time (PT) and hemolysis assay. It was found that the PT and APTT time was significantly prolonged for the fabricated PUCnCoHp ASD occluding patch compared to the control. Likewise, the hemolysis percentage was also decreased for the PUCnCoHp ASD patch against the control. In conclusion, the developed PUCnCoHp patch demonstrates potential properties to be used for ASD occlusion.

7.
Polymers (Basel) ; 9(5)2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-30970842

RESUMO

The objective of this work is to characterize and investigate the blood compatibility of polyurethane (PU)/mustard oil composites fabricated using electrospinning technique. The fabricated scaffold was characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), thermogravimetric analysis (TGA) and contact angle measurements. The activated partial thromboplastin time (APPT), prothrombin time (PT) and the hemolytic assay were done to investigate the blood compatibility of the developed composites. The SEM results revealed that the fiber diameter of the composites (761 ± 123 nm) was reduced compared to pristine PU control. The interaction between PU and mustard oil was confirmed by FTIR as evident through the shifting of peaks. The fabricated composites depicted hydrophobic behavior as insinuated by the increase in contact angle measurements. PU/mustard composites displayed improved crystallinity as confirmed by TGA. Atomic force micrographs suggested that developed PU/mustard oil composites showed an increase in the surface roughness (Ra) compared to pure PU. The Ra of pure PU was observed to be 723 nm but for the fabricated PU/mustard oil composite the Ra was found to be 1298 nm (Ra). The hemolytic index value for pure PU and fabricated composites was observed to be 2.73% and 1.15% indicating that developed composites showed a non-hemolytic behavior signifying the safety of the composites with red blood cells. Hence the newly developed composites with improved physicochemical and blood compatibility properties may be considered as a potential candidate for fabricating cardiac patches and grafts.

8.
An. acad. bras. ciênc ; 89(3,supl): 2411-2422, 2017. graf
Artigo em Inglês | LILACS | ID: biblio-886815

RESUMO

ABSTRACT In this work, the physicochemical and blood compatibility properties of prepared PU/Bio oil nanocomposites were investigated. Scanning electron microscope (SEM) studies revealed the reduction of mean fiber diameter (709 ± 211 nm) compared to the pristine PU (969 nm ± 217 nm). Fourier transform infrared spectroscopy (FTIR) analysis exposed the characteristic peaks of pristine PU. Composite peak intensities were decreased insinuating the interaction of the bio oilTM with the PU. Contact angle analysis portrayed the hydrophobic nature of the fabricated patch compared to pristine PU. Thermal gravimetric analysis (TGA) depicted the better thermal stability of the novel nanocomposite patch and its different thermal behavior in contrast with the pristine PU. Atomic force microscopy (AFM) analysis revealed the increase in the surface roughness of the composite patch. Activated partial thromboplastin time (APTT) and prothrombin time (PT) signified the novel nanocomposite patch ability in reducing the thrombogenicity and promoting the anticoagulant nature. Finally the hemolytic percentage of the fabricated composite was in the acceptable range revealing its safety and compatibility with the red blood cells. To reinstate, the fabricated patch renders promising physicochemical and blood compatible nature making it a new putative candidate for wound healing application.


Assuntos
Humanos , Poliuretanos/química , Teste de Materiais , Nanocompostos/ultraestrutura , Propriedades de Superfície , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Nanocompostos/química , Membranas Artificiais
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