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1.
Saudi J Biol Sci ; 29(3): 1543-1549, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35280563

RESUMEN

Bisphenol-A (BPA), an organic compound with two phenol functional groups, is a widely used industrial plasticizer with known estrogenic properties. It is used in the manufacture of epoxy resins and polycarbonate plastics. This study was designed to evaluate and assess the possible toxicity arising from the oral administration of BPA to pregnant mice. Pregnant SWR/J mice (15 mice/group) were administrated oral doses of BPA (125, 250 and 500 mg/kg/day) over the course of five-day intervals during gestation (D1-5, D6-10 and D11-15), while control groups received only corn oil. The results indicated that BPA was associated with a reduction in the body weight of the pregnant mice from around 2-3 days after administration until the end of gestation. The greatest effects were evident when the BPA was given during the later stages of pregnancy, and with higher doses. They also showed marked reduction in food intake and, to a lesser extent, in water intake. Furthermore, doses of BPA induced a reduction in implantation sites, lower foetal body weight and increased mortality rates. Abortion and foetal resorption rates were not affected by BPA administration, however. The above findings were concluded by discussing the possible mechanisms involved in producing these effects.

2.
Saudi J Biol Sci ; 28(12): 7190-7201, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34867022

RESUMEN

The diversity of natural phytochemicals represents an unlimited source for discovery and development of new drugs. Ochradenus arabicus, (family: Resedaceae) a notable medicinal plant displays a high content of flavonoid glycosides. This study investigates a possible preventative role of zinc nanoparticles biosynthesized by O. arabicus leaf extracts (OAZnO NPs) in limiting genotoxicity and cytotoxicity caused by indole acetic acid (IAA) in laboratory mice. ZnO NPs were synthesized using O. arabicus leaf extracts and characterized with UV-visible spectroscopy, scanning electron microscopy (SEM) and X-Ray diffraction (XRD). The mice were randomly distributed into the following six groups: control, OAZnO NPs treated (10 mg/kg BW), IAA treated (50 mg/kg BW); simultaneous treatment, pre-treatment, and post-treatment. Reactive oxygen species (ROS), DNA damage, chromosome aberration, and apoptosis were analyzed as toxicity endpoints. IAA exposure significantly induced production of ROS, DNA damage, apoptosis, chromosome aberrations, and micronuclei. Pre-, post-, and simultaneous treatment with OAZnO NPs ameliorated the damage caused by IAA exposure. Exposure to OAZnO NPs alone caused no toxicity for any endpoint based on comparison to controls. This study demonstrated that IAA-induced cytotoxic damage in mice could be ameliorated by treatment with OAZnO NPs. These findings require additional verification in mechanistic and in vitro studies.

3.
Ultrason Sonochem ; 68: 105071, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32505099

RESUMEN

Nanoball-structured ferromagnetic zinc ferrite nanocrystals (ZnFe2O4 NPs) entrapped with graphitic-carbon nitride (g-C3N4) was produced via straightforward and facile sonochemical synthetical technique (titanium probe; 100 W/cm2 and 50 KHz). The morphological (SEM), elemental (EDS), diffraction (XRD), XPS, and electrochemical studies (CV) have been carry out to verify the nanostructure and shape of the materials. The ZnFe2O4 NPs/g-C3N4 electrode (GCE) was constructed which displayed outstanding electrochemical ability towards toxic 4-nitrophenol (NTP). A sensitive, selective, reproducible, and durable electrochemical NTP sensor was developed by ZnFe2O4 NPs/g-C3N4 modified electrode. The modified sensor exhibited a high sensitivity and 4.17 nanomolars of LOD. It's greater than the LOD of previously reported NTP modified sensors. The real-time experiments of the modified electrochemical (ZnFe2O4 NPs/g-C3N4 electrode) sensor were successfully explained in various water (river and drinking) samples and its showed high standard recoveries. Therefore, sonochemical synthetical method and fabrication of modified electrode were developed this work based on environmental analysis of NTP sensor.

4.
Ultrason Sonochem ; 66: 105072, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32229388

RESUMEN

Copper (Cu) based metal oxides have high electrocatalytic ability. In this work, we are synthesized stone-like cuprous oxide particles (Cu2O SNPs) covered on acid functionalized graphene oxide (GOS) sheets using ultrasonic process (50 kHz and 100 W). Besides, the chemical structural and crystalline analyses of Cu2O SNPs@GOS composites were characterized by transmission electron microscopy, X-ray crystallography and energy-dispersive X-ray spectroscopy. The Cu2O SNPs@GOS nanomaterials were tested towards detection of 8-hydroxydeoxyguanosine (8-OHdG) in biological samples. As expected Cu2O SNPs@GOS catalyst modified electrodes performed an outstanding catalytic ability on 8-hydroxydeoxyguanosine oxidation. 8-OHdG is oxidative stress biomarker. Further, it is noted that the detection performance of Cu2O SNPs@GOS coated electrodes and it's highly enhanced due to the synergistic effect of Cu2O SNPs and GOS. Besides, the modified materials provide more electro-active faces and as well as rapid electron transport pathway and shorten diffusion. Moreover, oxidation of 8-OHdG sensor is exploring a long linear or working range of 0.02-1465 µM and high sensitivity (8.75 nM). The viability of the Cu2O SNPs@GOS proposed electrochemical methods have tested, to find out 8-OHdG concentrations in biological fluids (blood serum and urine) with a satisfying recovery ranges.


Asunto(s)
Carbono/química , Cobre/química , Electroquímica/instrumentación , Nanoestructuras/química , Ondas Ultrasónicas , 8-Hidroxi-2'-Desoxicoguanosina/sangre , 8-Hidroxi-2'-Desoxicoguanosina/orina , Grafito/química , Humanos
5.
Ultrason Sonochem ; 64: 105006, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32146332

RESUMEN

A novel network-like magnetic nanoparticle was fabricated on a graphitic carbon nitride through a facile sonochemical route at frequency 20 kHz and power 70 W. To enhance the electrocatalytic activity of the modified materials, the graphitic carbon nitrides (g-C3N4) was prepared from melamine. Monitoring of xanthine concentration level in biological fluids is more important for clinical diagnosis and medical applications. As modified CuFe2O4/g-C3N4 nanocomposite exhibits better electrochemical activity towards the oxidation of xanthine with higher anodic current compared to other modified and unmodified electrode for the detection of xanthine with larger linear range (0.03-695 µM) and lower limit of detection (13.2 nM). To compare with these methods, the electrochemical techniques may be an alternative high sensitive method due to their simplicity and rapid detection time. In addition, the practical feasibility of the sensor was inspected with biological samples, reveals the acceptable recovery of the sensor in real samples.

6.
Ultrason Sonochem ; 63: 104902, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31951998

RESUMEN

Herein, the synthesis of copper ferrite nanoparticles (CuFe2O4 NPs)/chitosan have been prepared by sonochemical route under ultrasonic irradiation bath at 40 kHz and 50 W. A high sensitive and stable modified electrochemical sensor was developed using a composition of copper ferrite nanoparticles coordinated with biopolymer through a facile ultrasound approach. Besides, power and frequency parameters are highly important for sonochemical synthesis and specifically structure, and size of the nanomaterials development during the ultrasonic irradiation time. In this work, ultrasonic bath was used to synthesis of CuFe2O4 nanomaterial at 40 kHz with 1 h. CuFe2O4/chitosan was characterized by FESEM, EDX, XRD and electrochemical methods. Furthermore, 8-hydroxyguanine is one of biomarker by oxidative stress. The concentrations of 8-hydroxyguanine within a cell are a measurement of oxidative stress in human body. Consequently, the measurement of 8-hydroxyguanine in blood serum samples with high specificity is of greatest importance. The CuFe2O4/chitosan modified electrode is displayed a low detection limit of 8.6 nM and long linear range (0.025-697.175 µM).


Asunto(s)
Quitosano/química , Cobre/química , Técnicas Electroquímicas/instrumentación , Compuestos Férricos/química , Nanopartículas/química , Humanos , Límite de Detección , Estrés Oxidativo
7.
Mikrochim Acta ; 185(11): 520, 2018 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-30367266

RESUMEN

A voltammetric sensor is described for the quantitation of propyl gallate (PG). A screen-printed carbon electrode (SPCE) was modified with reduced graphene sheets that were decorated with cobalt diselenide nanoparticles (CoSe2@rGO). The material was hydrothermally prepared and characterized by several spectroscopic techniques. The modified SPCE displays excellent electrocatalytic ability towards PG. Differential pulse voltammetry, with a peak voltage at 0.34 V (vs. Ag/AgCl) has a sensitivity of 12.84 µA·µM-1·cm-2 and a detection limit as low as 16 nM. The method is reproducible, selective, and practical. This method was applied to the determination of PG in spiked meat samples, and the result showed an adequate recovery. Graphical abstract Schematic of a new method for fast and sensitive electrochemical determination of the food additive propyl gallate in meat.


Asunto(s)
Cobalto/química , Técnicas Electroquímicas/métodos , Carne/análisis , Galato de Propilo/análisis , Selenio/química , Antioxidantes/análisis , Técnicas Electroquímicas/normas , Electrodos , Aditivos Alimentarios/análisis , Grafito/química , Límite de Detección , Óxidos/química
8.
Mikrochim Acta ; 185(6): 313, 2018 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-29860537

RESUMEN

A new type of manganese diselenide nanoparticles (MnSeNPs) was synthesized by using a hydrothermal method. Their surface morphology, crystallinity and elemental distribution were characterized by using transmission electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy which scrutinize the formation of the NPs. The NPs were coated on a glassy carbon electrode (GCE), and electrochemical impedance spectroscopy, cyclic voltammetry and differential pulse voltammetry were applied to study the electroanalytical properties towards the oxidation of the food additive capsaicin. The modified GCE displays lower charge transfer resistance (R ct = 29.52 Ω), a larger active surface area (0.089 cm2/g, and more efficient electrochemical oxidation of capsaicin compared to a MnS2/GCE and a bare GCE. The oxidation peak potential is 0.43 V (vs. Ag/AgCl) which is lower than that of previously reported GCEs. The sensor has a detection limit as low as 0.05 µM and an electrochemical sensitivity of 2.41 µA µM-1 cm-2. The method was applied to the determination of capsaicin in pepper samples. Graphical abstract Electrochemical determination of capsaicin in pepper extract by using MnSeNPs modified electrode.


Asunto(s)
Capsaicina/análisis , Carbono/química , Electroquímica/instrumentación , Compuestos de Manganeso/química , Nanopartículas/química , Compuestos de Selenio/química , Técnicas de Química Sintética , Electrodos , Vidrio/química , Concentración de Iones de Hidrógeno , Límite de Detección , Nanotecnología , Piper/química
9.
Saudi J Biol Sci ; 25(1): 22-26, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29379351

RESUMEN

The information on the hepatoprotective effect of Bauhinia malabarica Roxb. (Family Leguminosae) used in the folkloric medical practice in Malabar coast and Walayar valley of southern India for the treatment of liver related disorders is completely unknown. Hence, the efficacy of the aqueous methanolic extract of stem bark of B. malabarica (AqMeOH-Ba) was evaluated for liver function serum biochemical markers along with the antioxidant markers in liver tissues of Wistar albino rats. The biochemical observations as well as the histopathological examination of liver sections manifested considerable hepatoprotective activity of B. malabarica stem bark, and thus validated the folkloric claim.

10.
J Colloid Interface Sci ; 505: 1193-1201, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28738516

RESUMEN

We described a three-dimensional Mn3O4 microcubes (3D-Mn3O4MCs) synthesised via a facile hydrothermal route for the determination of nimorazole (NMZ), an important drug that used in the treatment of head and neck cancer. The 3D-Mn3O4 MCs possess large active area and high conductivity, and 3D-Mn3O4 MCs film modified screen-printed carbon electrode (3D-Mn3O4MCs/SPCE) was fabricated which displayed excellent electrocatalytic ability towards NMZ. Under optimised working conditions, the modified electrode responded linearly to NMZ in the 0.025-8060µM concentration range and the detection limit was 6nM. A rapid, sensitive, selective, reproducible, and durable sensor was described. The practical feasibility of the sensor was demonstrated in human serum and NMZ tablet samples. The obtained results revealed the potential real-time applicability of the sensing device in biological analysis and pharmaceutical formulations.


Asunto(s)
Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Electrodos , Neoplasias de Cabeza y Cuello , Compuestos de Manganeso/química , Nimorazol/sangre , Óxidos/química , Comprimidos/metabolismo , Antitricomonas/sangre , Carbono/química , Humanos
11.
Saudi J Biol Sci ; 24(2): 379-388, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28149177

RESUMEN

Protein-protein interaction is a vital process which drives many important physiological processes in the cell and has also been implicated in several diseases. Though the protein-protein interaction network is quite complex but understanding its interacting partners using both in silico as well as molecular biology techniques can provide better insights for targeting such interactions. Targeting protein-protein interaction with small molecules is a challenging task because of druggability issues. Nevertheless, several studies on the kinetics as well as thermodynamic properties of protein-protein interactions have immensely contributed toward better understanding of the affinity of these complexes. But, more recent studies on hot spots and interface residues have opened up new avenues in the drug discovery process. This approach has been used in the design of hot spot based modulators targeting protein-protein interaction with the objective of normalizing such interactions.

12.
J Colloid Interface Sci ; 485: 123-128, 2017 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-27662023

RESUMEN

To date, the development of different modified electrodes have received much attention in electrochemistry. The modified electrodes have some drawbacks such as high cost, difficult to handle and not eco friendly. Hence, we report an electrochemical sensor for the determination of palladium ions (Pd2+) using an un-modified screen printed carbon electrode has been developed for the first time, which are characterized and studied via scanning electron microscope and cyclic voltammetry. Prior to determination of Pd2+ ions, the operational conditions of un-modified SPCE was optimized using cyclic voltammetry and showed excellent electro-analytical behavior towards the determination of Pd2+ ions. Electrochemical determination of Pd2+ ions reveal that the un-modified electrode showed lower detection limit of 1.32µM with a linear ranging from 3 to 133.35µM towards the Pd2+ ions concentration via differential pulse voltammetry. The developed sensor also applied to the successfully determination of trace level Pd2+ ions in spiked water samples. In addition, the advantage of this type of electrode is simple, disposable and cost effective in electrochemical sensors.

13.
J Colloid Interface Sci ; 487: 289-296, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-27792936

RESUMEN

A novel electrochemical sensor based on the functionalized multiwalled carbon nanotube (f-MWCNT) was successfully developed for the sensitive and selective determination of non-steroidal prostate anti-cancer drug nilutamide in tablet and blood serum samples. The f-MWCNT was prepared by the simple reflux method and characterized by the scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, X-ray powder diffraction (XRD) and fourier transform infrared spectroscopy (FT-IR). Interestingly, the f-MWCNT was exhibited a superior electrocatalytic activity towards the anti-cancer drug nilutamide when compared with pristine MWCNT and unmodified electrodes. Besides, the electrochemical sensor was revealed an excellent current response for the determination of nilutamide with wide linear ranges (0.01-21µM and 28-535µM), high sensitivity (11.023 and 1.412µA µM-1cm2) and very low detection limit (LOD) 0.2nM. The developed electrochemical sensor was showed an excellent selectivity even in the presence of electrochemically active biological substances and nitro aromatic compounds. Moreover, it manifested a good reproducibility and stability. In addition, the f-MWCNT modified glassy carbon electrode (GCE) sensor was successfully applied for the detection of nilutamide in tablet and blood serum sample.


Asunto(s)
Antagonistas de Andrógenos/sangre , Antineoplásicos/sangre , Técnicas Biosensibles , Técnicas Electroquímicas , Imidazolidinas/sangre , Nanotubos de Carbono/química , Electrodos , Humanos , Límite de Detección , Nanotubos de Carbono/ultraestructura , Reproducibilidad de los Resultados , Comprimidos
14.
Mater Sci Eng C Mater Biol Appl ; 56: 374-9, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26249603

RESUMEN

Development of biologically inspired green synthesis of silver nanoparticles is evolving into an important branch of nano-biotechnology. In the present investigation, we report the green synthesis of silver nanoparticles (AgNPs) employing the leaf extract of Justicia glauca. Water-soluble organics present in the leaf extract are mainly responsible for the reduction of silver nitrate (AgNO3) solution to AgNPs. The AgNPs are 10-20nm in dimensions as determined by TEM images. The antimicrobial activities of green synthesized AgNPs and drug blended AgNPs have been evaluated against the dental caries and periodontal disease causing microorganisms such as Streptococcus mutans, Staphylococcus aureus, Lactobacillus acidophilus, Micrococcus luteus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. The AgNPs and drug blended AgNPs show a significant antibacterial and antifungal activity. Minimum inhibitory concentration (MIC) value of AgNPs determined against the selected dental caries and periodontal disease causing microorganisms are noticeable between the range of 25-75µg/mL.


Asunto(s)
Antibacterianos , Caries Dental , Género Justicia/química , Nanopartículas del Metal/química , Periodontitis , Plata/química , Antibacterianos/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Bacterias/crecimiento & desarrollo , Candida albicans/crecimiento & desarrollo , Caries Dental/tratamiento farmacológico , Caries Dental/microbiología , Periodontitis/tratamiento farmacológico , Periodontitis/microbiología , Extractos Vegetales/química , Hojas de la Planta/química
15.
Analyst ; 140(16): 5764-71, 2015 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-26171468

RESUMEN

Amitrole is a biologically toxic nonselective herbicide which contaminates surface and ground waters at unprecedented rates. All reported modified electrodes that detect amitrole within sub-micromolar to nanomolar levels were based on the electro-oxidation of amitrole. Herein, we developed a new conceptual idea to detect picomolar concentrations of amitrole based on calcium cross linked pectin stabilized gold nanoparticle (CCLP-GNP) film modified electrode which was prepared by electrodeposition. When the electrochemical behavior of amitrole was investigated at the CCLP-GNP film, the reduction peak current of the GNPs linearly decreased as the concentration of amitrole increases. We have designed a determination platform based on the amitrole dependent decrease of the GNP cathodic peak. The described concept and high sensitivity of square wave voltammetry together facilitate the great sensing ability; as a result the described approach is able to reach a low detection limit of 36 pM which surpassed the detection limits of existing protocols. The sensor presents a good ability to determine amitrole in two linear concentration ranges: (1) 100 pM-1500 pM with a detection limit of 36 pM; (2) 100 nM-1500 nM with a detection limit of 20 nM. The preparation of CCLP-GNPs is simple, rapid and does not require any reducing agents.


Asunto(s)
Amitrol (Herbicida)/análisis , Técnicas de Química Analítica/métodos , Oro/química , Nanopartículas/química , Pectinas/química , Amitrol (Herbicida)/química , Calcio/química , Técnicas Electroquímicas , Límite de Detección
16.
Saudi J Biol Sci ; 21(3): 204-31, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24955007

RESUMEN

The discipline taxonomy (the science of naming and classifying organisms, the original bioinformatics and a basis for all biology) is fundamentally important in ensuring the quality of life of future human generation on the earth; yet over the past few decades, the teaching and research funding in taxonomy have declined because of its classical way of practice which lead the discipline many a times to a subject of opinion, and this ultimately gave birth to several problems and challenges, and therefore the taxonomist became an endangered race in the era of genomics. Now taxonomy suddenly became fashionable again due to revolutionary approaches in taxonomy called DNA barcoding (a novel technology to provide rapid, accurate, and automated species identifications using short orthologous DNA sequences). In DNA barcoding, complete data set can be obtained from a single specimen irrespective to morphological or life stage characters. The core idea of DNA barcoding is based on the fact that the highly conserved stretches of DNA, either coding or non coding regions, vary at very minor degree during the evolution within the species. Sequences suggested to be useful in DNA barcoding include cytoplasmic mitochondrial DNA (e.g. cox1) and chloroplast DNA (e.g. rbcL, trnL-F, matK, ndhF, and atpB rbcL), and nuclear DNA (ITS, and house keeping genes e.g. gapdh). The plant DNA barcoding is now transitioning the epitome of species identification; and thus, ultimately helping in the molecularization of taxonomy, a need of the hour. The 'DNA barcodes' show promise in providing a practical, standardized, species-level identification tool that can be used for biodiversity assessment, life history and ecological studies, forensic analysis, and many more.

17.
Saudi J Biol Sci ; 19(4): 465-71, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23961208

RESUMEN

We have reported the modification of biomolecule with nanomaterials. In this paper, the electrochemical response of different FAD-dependent enzymes at carbon nanomaterials modified electrode. The modified electrode also exhibits a promising enhanced electrocatalytic activity toward the oxidation of substrate. Different methods were used for fabrication of modified electrode. The presence of nanomaterials enhances the enzyme loading and stability. Cyclic voltammograms (CVs) were used for the determination of substrate and the apparent coefficient values for these compounds at different electrodes. Finally, we have studied the surface morphology of the modified electrode using scanning electron microscopy (SEM), which revealed that enzyme is coated on nanomaterials.

19.
Saudi J Biol Sci ; 18(2): 123-7, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23961114

RESUMEN

Internal transcribed spacer (ITS) region of nuclear ribosomal DNA from 16 populations of Persicaria barbata (L.) H. Hara (Polygonaceae) belonging to five geographical locations of India (Arunachal Pradesh, Himachal Pradesh, Bihar, Karnataka and Andaman Island) was sequenced. Analysis of nucleotide sequences reveals polymorphism among the populations. UPGMA analysis conducted on the ITS datasets shows that the sampled populations of P. barbata are grouped according to their geographic locations and are supposed to be evolved under reproductive isolation which most probably are due to the long distance distribution and population fragmentation.

20.
Saudi J Biol Sci ; 17(4): 275-290, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30323708

RESUMEN

The internal transcribed spacer (ITS) region of nuclear ribosomal DNA, trnL and trnL-F genes of Cardamine glechomifolia Levl. (family Brassicaceae) were sequenced and analyzed with the sequence of related Cardamine species retrieved from NCBI GenBank to detect pattern of evolutionary differentiation. All trees resulting from combined sequence analyses data of ITS, trnL and trnL-F gene resolve that C. glechomifolia - an endemic species to South Korea clade with Cardamine microzyga (100% bootstrap support). The evolutionary history was inferred using the Maximum Parsimony method. The consistency index is (0.588235), the retention index is (0.687500), and the composite index is 0.519622 (0.404412) for all sites and parsimony-informative sites (in parentheses). The result of the analysis using Maximum Parsimony was found congruence with Maximum Likelihood method and in Baseyan analysis.

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