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1.
Saudi J Biol Sci ; 29(4): 2270-2279, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35531172

RESUMEN

Zinc and its derivatives requirement increased to enhance human immunity against the different pandemics, including covid-19. Green synthesis is an emerging field of research. Zinc oxide (ZnO) nanoparticles have been prepared from Anoectochilus elatus and characterized using absorption, vibrational and electron microscope analysis. They were carried for antibacterial, inflammatory control tendency, and potential antioxidant activities. The brine shrimp lethal assay tested the biologically derived nanomaterial toxicity and the lethal concentration (LC50) is 599.79 µg/ml. The inhibition against the important disease-causing pathogens was measured against four-gram negative, gram-positive bacteria and two fungus pathogens. The nanomaterial exposed inhibition zone for gram-positive bacteria between 17 mm and 25 mm. The inhibition zone against gram-negative bacteria exists between 19 mm and 24 mm. The anti-inflammatory activity was assessed by inhibition of protein denaturation and protease inhibitory activity using nanomaterial. The antioxidant activity was examined using four assays for the therapeutic activities. The average size range of 60-80 nm nanoparticles has prepared and exposed the good biological activity between 50 µg/ml and 100 µg/ml. The comparative results of anti-inflammatory and antioxidant assay results with standards such as Aspirin and vitamin C exposed that two to three times higher concentrations are required for the fifty percent of inhibitions. The prepared low-cost nanoparticle has exhibited excellent biological activity without any side effects and may enhance immunity.

2.
J Mater Chem B ; 10(14): 2296-2315, 2022 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-35060581

RESUMEN

Medical devices and surgical implants are necessary for tissue engineering and regenerative medicines. However, the biofouling and microbial colonization on the implant surface continues to be a major concern, which is difficult to eradicate and typically necessitates either antibiotic therapy or implant removal. As a result, efficient and eco-friendly bioinspired coating strategies for tethering functional materials or molecules on different medical substrates are highly desirable, especially for endowing versatile surface functionalities. Tannic acid (TA), a well-known tea stain polyphenol, has a good affinity for various substrates and actively inhibits the adhesion and colonization of microbes. Thus, functionalization of polymers, nanomaterials, metal-phenolic networks (MPNs), and proteins using TA bestows the end-products with unique binding or anchoring abilities on various implantable surfaces. This review addresses the recent advancements in the essential biomedical perspective of TA-based bioinspired universal surface coating technologies by focusing on their intrinsic features and ability to produce engineered functional composites. Further, the possible contributions of TA-based composites in antifouling and antibacterial applications on various biomedical substrates are outlined.


Asunto(s)
Incrustaciones Biológicas , Taninos , Antibacterianos/química , Antibacterianos/farmacología , Incrustaciones Biológicas/prevención & control , Polímeros/química , Propiedades de Superficie , Taninos/química , Taninos/farmacología
3.
Saudi J Biol Sci ; 28(12): 6692-6700, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34866967

RESUMEN

The pumpkin pulp contains a greater composition of edible polysaccharides and has reported with excellent biological applications. This research pertains to optimize the extraction of polysaccharides from the fleshy portion of the pumpkin using aqueous assisted extraction (AAE). The result showed that the optimal extraction condition of pumpkin polysaccharide was as follows: extraction temperature at 55 °C, pH 4.5, and enzyme concentration of 4000 µ/g for 80 min. Under the optimal extraction condition, the yield of pumpkin polysaccharide via AAE (15.4) was significantly higher. The biological activities of extracted polysaccharide including α-amylase inhibition (57.41% at 1000 µg/mL) and anti-inflammatory (50.41% at 25 µg/mL) activity increased significantly. Additionally, the antioxidant activities of extracted pumpkin polysaccharides including IC50 values of DPPH and ABTS were 59.87% and 58.74%, respectively. The pumpkin polysaccharide has maximum inhibitory effects against bacterial strains especially for Escherichia coli than that of fungal strains. It is suggested that the aqueous assisted extraction of is a cost-effective promising method to decrease the processing time as well as enhancing extracted polysaccharide yield - times.

4.
ACS Appl Mater Interfaces ; 13(17): 20708-20717, 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33900718

RESUMEN

The marked increase in bacterial colonization of medical devices and multiple drug resistance to traditional antibiotics underline the pressing need for developing novel antibacterial surface coatings. In the present investigation, natural polyphenol tannic acid (TA)-capped silver nanoparticles (TA-Ag NPs) were synthesized via an environmentally friendly and sustainable one-step redox reaction under UV irradiation with a simultaneous and uniform deposition on polydimethylsiloxane (PDMS) and other substrate surfaces. In the synthesis process, the dihydroxyphenyl and trihydroxyphenyl groups of TA actively participate in Ag+ reduction, forming co-ordination linkages with Ag NPs and bestowing the deposition on the PDMS surface. The physico-chemical features of TA-Ag NPs were characterized in detail. Microscopic examination, surface elemental analysis, and wettability measurements clearly reveal the decoration of TA-Ag NPs on the substrate surfaces. The modified PDMS surfaces can kill the adhered bacteria or resist the bacterial adhesion, and no live bacteria can be found on their surfaces. Most importantly, the modified PDMS surfaces exhibit predominant antibacterial effects both in vitro in the catheter bridge model and in vivo in a rat subcutaneous infection model. On the other hand, the functionalized surfaces exhibit only a negligible level of cytotoxicity against L929 mouse fibroblasts with no side effects on the major organs of Sprague-Dawley rats after implantation, indicating their biocompatibility for potential biomedical applications.


Asunto(s)
Antibacterianos/química , Nanocompuestos/química , Plata/química , Taninos/química , Rayos Ultravioleta , Animales , Dimetilpolisiloxanos/química , Ratas , Ratas Sprague-Dawley
5.
Saudi J Biol Sci ; 28(3): 1808-1815, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33732066

RESUMEN

The present work aims to synthesize zinc oxide (ZnO) nanoparticles via green approaches using leaf extract of Parthenium hysterophorus. UV-vis and FT-IR tests confirmed the existence of biomolecules, active materials, and metal oxides. The X-ray diffraction structural study exposes the ZnO nanoparticles formation with hexagonal phase structures. SEM and TEM analysis reveal surface morphologies of ZnO nanoparticles and most of them are spherical with a size range of 10 nm. ZnO nanoparticles were revealed strong antimicrobial activity against both bacterial and fungal strains. The germination of seeds and vegetative growth of Sesamum indicum has been greatly improved.

6.
Colloids Surf B Biointerfaces ; 200: 111592, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33556756

RESUMEN

Titanium (Ti) and its alloys are primarily explored to produce biomedical implants owing to their improved mechanical stability, corrosion resistance, low density, and good biocompatibility. Despite, Ti substrate surfaces are easily contaminated by plasma proteins and bacteria. Herein, a simple one-step process for the simultaneous deposition of a polyphenol tannic acid (TA) and four-armed poly(ethylene glycol) (PEG10k-4-OH) on the Ti substrate (Ti-TA/PEG) surface was described. Additionally, a two-step process has been employed to fabricate the Ti-TA-PEG surface via successive deposition of TA and PEG10k-4-OH for comparison. The resultant Ti-TA/PEG surface prepared by simultaneous deposition of TA and PEG10k-4-OH exhibits higher coating thickness and better surface coverage than the Ti-TA-PEG surface. The Ti-TA/PEG and Ti-TA-PEG surfaces could actively inhibit the non-specific adsorption of proteins, suppress the bacterial and platelet adhesion, and prevents biofilm formation. Moreover, the Ti-TA/PEG surface displays a better antifouling performance than the Ti-TA-PEG surface. Thus, the present study demonstrates a simple and convenient approach for constructing polymeric coating with good anti-adhesive properties on the Ti substrate surface.


Asunto(s)
Incrustaciones Biológicas , Titanio , Incrustaciones Biológicas/prevención & control , Polietilenglicoles , Propiedades de Superficie , Taninos
7.
Photodiagnosis Photodyn Ther ; 33: 102148, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33346056

RESUMEN

A simple method has been needed to synthesize nanoparticles (NPs) to avoid environmental pollution, an alternative chemical and physical method. This current study deals with phytosynthesis of gold (Au) and platinum (Pt) metal doped with titanium oxide (TiO2) NPs using Enterolobium saman bark extract. This extract plays a vital role in reducing and stabilizing Au and Pt doped into the TiO2 NPs lattices. Phytosynthesized samples were characterized by XRD, SEM, ED-XRF, TEM, FTIR, Raman, and UV-vis-DRS analyses. The metal doping effect has decreased bandgap energy and particle size, whereas increased conductivity for TiO2/M-Au and TiO2/M-Pt NPs compared to pristine TiO2 NPs. Phytosynthesized NPs were fabricated for dye-sensitized solar cell (DSSC) and photocatalytic behaviour against methylene blue (MB) dye was studied. An obtained result demonstrates that TiO2/M-Au NPs have excellent feasibility for applying DSSC and photocatalytic application due to particle size, crystallite size, absorption ability, and bandgap energy. Besides, synthesized samples were measured with cyclic voltammetry and impedance spectroscopy found that the metal doping is drifted the dielectric and increases that the metal doping is drifted the dielectric increases electro-catalytic of the TiO2. Different concentrations of all NPs were tested against Escherichia coli MTCC 40 and S. aureus ATCC 6633 bacteria by a well-diffusion method. The 10 mg concentration of all NPs showed better antibacterial activity. However, we believe that the proposed simple phytosynthesized method provides an efficient way to overcome the chemical and physical methods.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Fotoquimioterapia , Antibacterianos/farmacología , Oro , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes , Platino (Metal) , Staphylococcus aureus , Titanio
8.
Sci Rep ; 10(1): 18912, 2020 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-33144607

RESUMEN

A hybrid and straightforward nanosystem that can be used simultaneously for cancer-targeted fluorescence imaging and targeted drug delivery in vitro was reported in this study. A chitosan (CS) polymer coated with reduced graphene oxide (rGO) and implanted with Fe3O4 nanoparticles was fabricated. The fundamental physicochemical properties were confirmed via FT-IR, XRD, FE-SEM, HR-TEM, XPS, and VSM analysis. The in vivo toxicity study in zebrafish showed that the nanocomposite was not toxic. The in vitro drug loading amount was 0.448 mg/mL-1 for doxorubicin, an anticancer therapeutic, in the rGO/Fe3O4/CS nanocomposite. Furthermore, the pH-regulated release was observed using folic acid. Cellular uptake and multimodal imaging revealed the benefit of the folic acid-conjugated nanocomposite as a drug carrier, which remarkably improves the doxorubicin accumulation inside the cancer cells over-express folate receptors. The rGO/Fe3O4/CS nanocomposite showed enhanced antibiofilm and antioxidant properties compared to other materials. This study's outcomes support the use of the nanocomposite in targeted chemotherapy and the potential applications in the polymer, cosmetic, biomedical, and food industries.


Asunto(s)
Quitosano/química , Doxorrubicina/farmacología , Ácido Fólico/farmacología , Grafito/química , Neoplasias/metabolismo , Pez Cebra/crecimiento & desarrollo , Células A549 , Animales , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Sistemas de Liberación de Medicamentos , Ácido Fólico/química , Humanos , Células MCF-7 , Nanopartículas Magnéticas de Óxido de Hierro , Microscopía Fluorescente , Imagen Molecular , Nanocompuestos , Neoplasias/diagnóstico por imagen , Neoplasias/tratamiento farmacológico , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier , Pruebas de Toxicidad
9.
J Trace Elem Med Biol ; 50: 146-153, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30262272

RESUMEN

To develop novel nanoformulated insecticides and antimicrobials, herein we produced Ag nanoparticles (AgNPs) using the Bauhinia acuminata leaf extract. This unexpensive aqueous extract acted as a capping and reducing agent for the formation of AgNPs. We characterized B. acuminata-synthesized AgNPs by UV-vis and FTIR spectroscopy, XRD and TEM analyses. UV-vis spectroscopy analysis of B. acuminata-synthesized AgNPs showed a peak at 441.5 nm. FTIR shed light on functional groups from the phytoconstituents involved in nanosynthesis. XRD of B. acuminata-synthesized AgNPs suggested a face-centered cubic structure, with a highly crystalline nature. TEM of B. acuminata-synthesized AgNPs revealed mean size of 25 nm, with round shape. AgNPs tested at 60 µg/mL inhibited the growth of 5 bacteria and 3 fungal pathogens. In the insecticidal assays on important mosquito species, LC50 of the aqueous extract of B. acuminata leaves on the larvae of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus were 204.07, 226.02, and 249.24 µg/mL, respectively. The B. acuminata-synthesized AgNPs exhibited higher larvicidal efficacy, with LC50 values of 24.59, 27.19, and 30.19 µg/mL, respectively. Therefore, herein we developed a single-step, reliable, inexpensive, and environmentally non-toxic synthesis process to obtain AgNPs with high bioactivity against pathogens and vectors. Given the effective antimicrobial and larvicidal activity, nanoparticles fabricated using plant extracts and extremely low concentrations of trace elements, such as silver, can be exploited for multipurpose activities. Our results pointed out that B. acuminata-synthesized AgNPs have a promising potential in antimicrobial food packaging, as well as a foliar spray to control plant pathogens in the field, and to synergize the efficacy of fungicidal and larvicidal formulations.


Asunto(s)
Antiinfecciosos/química , Bauhinia/química , Insecticidas/química , Nanopartículas del Metal/química , Fitoquímicos/química , Extractos Vegetales/química , Plata/química , Animales , Espectroscopía Infrarroja por Transformada de Fourier
10.
Mater Sci Eng C Mater Biol Appl ; 90: 589-601, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29853129

RESUMEN

Nanomaterial-based drug carriers have become a hot spot of research at the interface of nanotechnology and biomedicine because they allow efficient loading, targeted delivery, controlled release of drugs, and therefore are promising for biomedical applications. The current study made an attempt to decorate the multiwalled carbon nanotubes (MWCNT) with titanium dioxide­gold nanoparticles in order to enhance the biocompatibility for doxorubicin (DOX) delivery. The successful synthesis of nano drug carrier (NDC) was confirmed by XRD, XPS and UV-Visible spectroscopy. FESEM and TEM revealed that the morphology of NDC can be controlled by manipulating the reaction duration, MWCNT concentration and TiO2-Au source concentration. Results showed that TiO2 and Au nanoparticles were well coated on MWCNT. NDC had finely tuned biocompatible properties, as elucidated by hemolytic and antimicrobial assays. NDC also showed a high antioxidant potential, 80.7% expressed as ascorbic acid equivalents. Commercial DOX drug was utilized to treat A549 and MCF7 cancer cell lines showing improved efficiency by formulating it with NDC, which selectively delivered at the pH 5.5 with drug loading capacity of 0.45 mg/mL. The drug releasing capacity achieved by NDC was 90.66% for 10 h, a performance that far encompasses a wide number of current literature reports.


Asunto(s)
Portadores de Fármacos/química , Nanopartículas del Metal/química , Nanotubos de Carbono/química , Titanio/química , Antineoplásicos/química , Antineoplásicos/farmacología , Biopelículas/efectos de los fármacos , Línea Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos/métodos , Oro/química , Humanos , Células MCF-7 , Microscopía Electrónica de Transmisión , Nanotecnología/métodos
11.
Environ Sci Pollut Res Int ; 25(11): 10482-10492, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28963600

RESUMEN

In the present scenario, the synthesis and characterization of zinc oxide (ZnO) and cerium oxide (CeO2) nanoparticles (NPs) through biological routes using green reducing agents are quite interesting to explore various biomedical and pharmaceutical applications, particularly for the treatment of cancer. This study was focused on the phytosynthesis of ZnO and CeO2 NPs using the leaf extract of Rubia cordifolia L. The active principles present in the plant extract were liable for rapid reduction of Zn and Ce ions to metallic nanocrystals. ZnO and CeO2 NPs were characterized by UV-visible spectroscopy, X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDAX), and photoluminescence (PL) techniques. ZnO and CeO2 NPs were partially agglomerated with a net-like structure. Biomedical activities of ZnO and CeO2 NPs were tested against MG-63 human osteosarcoma cells using MTT and reactive oxygen species (ROS) quantification assays. In treated cells, loss of cell membrane integrity, oxidative stress, and apoptosis was observed and it is well correlated with cellular damage immediately after induction. Overall, this study shed light on the anti-cancer potential of ZnO and CeO2 NPs on MG-63 human osteosarcoma cells through differential ROS production pathways, describing the potential role of greener synthesis.


Asunto(s)
Antibacterianos/farmacología , Cerio/química , Nanopartículas del Metal/química , Nanopartículas/química , Osteosarcoma/tratamiento farmacológico , Extractos Vegetales/farmacología , Óxido de Zinc/química , Antibacterianos/química , Línea Celular , Humanos , Microscopía Electrónica de Rastreo , Osteosarcoma/metabolismo , Espectroscopía de Fotoelectrones , Extractos Vegetales/química , Especies Reactivas de Oxígeno , Rubia , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier
12.
J Photochem Photobiol B ; 173: 598-605, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28697477

RESUMEN

The impact of green-fabricated gold nanoparticles on plant cells and non-target aquatic species is scarcely studied. In this research, we reported an environment friendly technique for the synthesis of gold nanoparticles (Au NPs) using the Sphaeranthus indicus leaf extract. The formation of the metal NPs was characterized by UV-Visible and FT-IR spectroscopy, XRD, SEM and TEM analyses. The UV-Visible spectra of Au NPs showed a surface plasmon resonance peak at 531nm. FT-IR analysis indicated functional bio-molecules associated with Au NPs formation. The crystalline nature of Au nanoparticles was confirmed by their XRD diffraction pattern. TEM revealed the spherical shape with a mean particle size of 25nm. Au NPs was tested at 0, 1, 3, 5, 7 and 10% doses in mitotic cell division assays, pollen germination experiments, and in vivo toxicity trials against the aquatic crustacean Artemia nauplii. Au NPs did not show any toxic effects on plant cells and aquatic invertebrates. Notably, Au NPs promoted mitotic cell division in Allium cepa root tip cells and germination of Gloriosa superba pollen grains. Au NPs showed no mortality on A. nauplii, all the tested animals showed 100% survivability. Therefore, these Au NPs have potential applications in the development of pollen germination media and plant tissue culture.


Asunto(s)
Asteraceae/química , Oro/química , Nanopartículas del Metal/química , Extractos Vegetales/química , Animales , Artemia/efectos de los fármacos , Asteraceae/metabolismo , Germinación/efectos de los fármacos , Tecnología Química Verde , Nanopartículas del Metal/toxicidad , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Células Vegetales/efectos de los fármacos , Células Vegetales/metabolismo , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
13.
J Photochem Photobiol B ; 167: 189-199, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28076823

RESUMEN

In the present study, we focused on a quick and green method to fabricate Ag, Au and Ag/Au alloy nanoparticles (NPs) using the bark extract of Guazuma ulmifolia L. Green synthesized metal NPs were characterized using different techniques, including UV-Vis spectroscopy, FT-IR, XRD, AFM and HR-TEM analyses. The production of Ag, Au and Ag/Au alloy NPs was observed monitoring color change from colorless to brown, followed by pink and dark brown, as confirmed by UV-Vis spectroscopy characteristic peaks at 436, 522 and 510nm, respectively. TEM shed light on the spherical shapes of NPs with size ranges of 10-15, 20-25 and 10-20nm. Biosynthesized NPs showed good catalytic activity reducing two organic dyes, 4-nitrophenol (4-NP) and Congo red (CR). UV-vis spectroscopy, fluorescence, circular dichroism spectroscopy and viscosity analyses were used to investigate the NP binding with calf thymus DNA. The binding constant of NPs with DNA calculated in UV-Vis absorption studies were 1.18×104, 1.83×104 and 2.91×104M-1, respectively, indicating that NPs were able to bind DNA with variable binding affinity: Ag/Au alloy NPs>Ag NPs>Au NPs. Ag/Au alloy NPs also showed binding activity to bovine serum albumin (BSA) over the other NPs. Ag and Ag/Au alloy NPs exhibited good antimicrobial activity on 14 species of microbial pathogens. In addition, the cytotoxic effects of Ag/Au alloy NPs were studied on human cervical cancer cells (HeLa) using MTT assay. Overall, our work showed the promising potential of bark-synthesized Ag and Ag/Au alloy NPs as cheap sources to develop novel and safer photocatalytic, antimicrobial and anticancer agents.


Asunto(s)
Malvaceae/química , Nanopartículas del Metal/química , Corteza de la Planta/química , Catálisis , Ensayos de Selección de Medicamentos Antitumorales , Oro/química , Células HeLa , Humanos , Pruebas de Sensibilidad Microbiana , Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión , Procesos Fotoquímicos , Plata/química , Análisis Espectral , Difracción de Rayos X
14.
Ecotoxicol Environ Saf ; 137: 149-157, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27918946

RESUMEN

Mosquitoes act as vectors of key pathogens and parasites. Plant essential oils have been recognized as important sources of biopesticides, which do not induce resistance and have limited toxic effects on human health and non-target organisms. In this research, we evaluated the larvicidal and oviposition deterrence activity of Hedychium larsenii essential oil (EO) and its major compounds ar-curcumene and epi-ß-bisabolol. Both molecules showed high toxicity against early third instars of Anopheles stephensi (LC50=10.45 and 14.68µg/ml), Aedes aegypti (LC50=11.24 and 15.83µg/ml) and Culex quinquefasciatus (LC50=12.24 and 17.27µg/ml). In addition, low doses of ar-curcumene and epi-ß-bisabolol were effective as oviposition deterrents against the three tested mosquito species. Notably, the acute toxicity of H. larsenii oil and its major compounds against the mosquito biocontrol agent Poecilia reticulata was low, with LC50 higher than 1500ppm. Overall, the results from this study revealed that ar-curcumene and epi-ß-bisabolol from the H. larsenii oil can be considered for the development of novel and effective mosquito larvicides.


Asunto(s)
Insecticidas/química , Mosquitos Vectores/crecimiento & desarrollo , Aceites Volátiles/farmacología , Sesquiterpenos/farmacología , Zingiberaceae/química , Aedes/crecimiento & desarrollo , Aedes/parasitología , Aedes/virología , Animales , Anopheles/crecimiento & desarrollo , Anopheles/parasitología , Anopheles/virología , Culex/crecimiento & desarrollo , Culex/parasitología , Culex/virología , Relación Dosis-Respuesta a Droga , Virus de la Encefalitis de San Luis , Larva , Dosificación Letal Mediana , Sesquiterpenos Monocíclicos , Mosquitos Vectores/parasitología , Mosquitos Vectores/virología , Oviposición , Extractos Vegetales/farmacología
15.
Microb Pathog ; 101: 1-11, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27765621

RESUMEN

The green fabrication of metal nanoparticles using botanical extracts is gaining increasing research attention in nanotechnology, since it does not require high energy inputs or the production of highly toxic chemical byproducts. Here, silver (Ag), gold (Au) and their bimetallic (Ag/Au) nanoparticles (NPs) were green synthesized using the Gloriosa superba aqueous leaf extract. Metal NPs were studied by spectroscopic (UV-visible spectroscopy, fluorescence spectroscopy, FT-IR spectroscopy, XRD and EDX) and microscopic (AFM and TEM) analysis. AFM and TEM showed that Ag and Au NPs had triangular and spherical morphologies, with an average size of 20 nm. Bimetallic Ag/Au NPs showed spherical shapes with an average size of 10 nm. Ag and Ag/Au bimetallic NPs showed high antibacterial and antibiofilm activities towards Gram-positive and Gram-negative bacteria. Overall, the proposed synthesis route of Ag, Au and Ag/Au bimetallic NPs can be exploited by the pharmaceutical industry to develop drugs effective in the fight against microbic infections.


Asunto(s)
Antibacterianos/metabolismo , Colchicaceae/química , Oro/metabolismo , Tecnología Química Verde/métodos , Nanopartículas del Metal/química , Extractos Vegetales/metabolismo , Plata/metabolismo , Bacterias/efectos de los fármacos , Biopelículas/efectos de los fármacos , Pruebas Antimicrobianas de Difusión por Disco , Nanopartículas del Metal/ultraestructura , Microscopía de Fuerza Atómica , Microscopía Electrónica de Transmisión , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Análisis Espectral
16.
Mater Sci Eng C Mater Biol Appl ; 49: 408-415, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25686966

RESUMEN

CeO2 nanoparticles (NPs) were green synthesized using Gloriosa superba L. leaf extract. The synthesized nanoparticles retained the cubic structure, which was confirmed by X-ray diffraction studies. The oxidation states of the elements (C (1s), O (1s) and Ce (3d)) were confirmed by XPS studies. TEM images showed that the NPs possessed spherical shape and particle size of 5nm. The Ce-O stretching bands were observed at 451cm(-1) and 457cm(-1) from the FT-IR and Raman spectra respectively. The band gap of the CeO2 NPs was estimated as 3.78eV from the UV-visible spectrum. From the photoluminescence measurements, the broad emission composed of eight different bands were found. The antibacterial studies performed against a set of bacterial strains showed that Gram positive (G+) bacteria were relatively more susceptible to the NPs than Gram negative (G-) bacteria. The toxicological behavior of CeO2 NPs was found due to the synthesized NPs with uneven ridges and oxygen defects in CeO2 NPs.


Asunto(s)
Antibacterianos/farmacología , Cerio/química , Liliaceae/química , Nanopartículas , Hojas de la Planta/química , Microscopía Electrónica de Transmisión , Análisis Espectral , Difracción de Rayos X
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