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1.
Heliyon ; 10(7): e28306, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38571616

RESUMO

Tuberculosis (TB), a deadly infectious disease, is primarily caused by the bacterium Mycobacterium tuberculosis. The misuse of antibiotics has led to the development of drug resistance, prompting researchers to explore new technologies to combat multidrug-resistant Tuberculosis (MDR TB). Phospholipid-based nanotherapeutics, such as nanoemulsions, are gaining traction as they enhance drug solubility, stability, and bioavailability. Our study focuses on the interaction between Bovine Serum Albumin (BSA) and a drug-loaded nanoemulsion based on Eugenol. This nanoemulsion incorporates Eugenol, Clove, cinnamon oil, and first-line anti-tuberculosis drugs like Rifampicin, Isoniazid, Pyrazinamide, and Ethambutol. The primary objective is to assess the biosafety profile of the nanoemulsion upon interaction with BSA. We employed Fluorescence, UV-visible, and Fourier Transform Infrared Spectroscopy (FTIR) to analyze this interaction. UV-visible spectroscopy detected changes in hydrophobicity due to structural alterations in BSA near the tryptophan residue, leading to the formation of ground-state complexes. Fluorescence spectroscopy demonstrated that the nanoemulsion effectively quenched fluorescence originating from tryptophan and tyrosine residues. Studies using synchronous and three-dimensional spectroscopy point to a potential modification of the aromatic environment of BSA by the nanoemulsion. Resonance light scattering spectra indicated the formation of large aggregates due to the interaction with the nanoemulsion. The second derivative FTIR spectra showed an increase in the magnitude of secondary structure bands, suggesting a conformational shift. This research has significant pharmacological implications for developing safer, more targeted drug delivery systems. The information obtained from the interaction of the nanoemulsion with the blood carrier protein is vital for the future development of superior carriers with minimal adverse effects on patients. It is crucial to remember that conformational changes brought on by drug-ligand complexes attaching to carrier proteins may have negative consequences. Therefore, this study enhances the in vitro evaluation of potential adverse effects of the nanoemulsion on serum proteins.

2.
J Environ Manage ; 254: 109812, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31733482

RESUMO

Antibiotics, one of the most abundant contaminants in the natural water systems possess various difficulties to remediate through conventional water treatment methods. Tetracycline (TC) remains one of the most widely used antibiotics for human and veterinary applications because of its broad-spectrum antibacterial activity. In the current study, we have employed nano zero-valent technology-based antibiotic remediation. In a first of its kind work, we applied bimetallic nZVI-Cu nanoparticles synthesized using pomegranate rind extract for remediation. TC removal of 72 ±â€¯0.5% (initial TC concentration 10 mg/L) was obtained with the nZVI-Cu concentration of 750 mg/L at pH 7. To overcome the colloidal instability and enhance TC removal further, the bimetallic nanoparticles were formed in-situ over bentonite. The bentonite supported composite (B/nZVI-Cu) was used to treat TC an initial concentration of 10 mg/L and the results confirmed significant enhancement in removal with a substantially decreased nanoparticle loading. Using only 150 mg/L of B/nZVI-Cu at pH 7, 95 ±â€¯0.05% of TC could be removed. The nanoparticles and the composites were characterized by SEM, FT-IR, and XRD analyses. The removal process was followed by UV-Visible analyses in conjunction with TOC, ORP and LCMS measurements. For treatment using B/nZVI-Cu, the reusability of the composite was established up to three cycles of operation, and the process was validated in the real water systems. Substantially decreased residual toxicity of the composite treated TC solution lends credence to the environmental sustainability of the process.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Poluentes Químicos da Água , Antibacterianos , Bentonita , Ferro , Espectroscopia de Infravermelho com Transformada de Fourier
3.
IET Nanobiotechnol ; 13(9): 928-932, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31811761

RESUMO

In recent years, nanoparticles especially with gold and silver nanoparticles based point of care diagnostic methods is being developed for the lethal diseases like dengue. This study focused to work on the dengue virus detection in a simplest method using gold nanoparticles probe (AuNPs) with thiol tagged single strand DNA (ss-DNA). A sensitive, fluorescence-based detection strategy was designed to examine and quantified the hybridisation process and also elucidated the behaviour of AuNPs before and after interaction of biomolecule. The detection process was focused on aggregation of gold nanoprobe in the presence of complementary strand (target region). Hence the percentage of aggregation was measured and as a result, the limit of detection was found to be 10-6 dilutions. Current detection method was highly sensitive, easy to perform and the reaction timing is rapid between 5 and 10 min, and it can be observed through naked eye.


Assuntos
Ouro/química , Nanopartículas/química , Ácidos Nucleicos/análise , Colorimetria/métodos , DNA de Cadeia Simples/química , Limite de Detecção , Reação em Cadeia da Polimerase/métodos , Espectrometria de Fluorescência/métodos
4.
Adv Clin Chem ; 91: 181-200, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31331489

RESUMO

High incidence of oral carcinoma and its late-stage presentation are the major global healthcare issues. The World Health Organization (WHO) has set early diagnosis and prevention of oral cancer as their primary objective. It is important to consider the time of oral screening, as it plays a pivotal role in understanding the disease prognosis. Critical signs and symptoms that can be identified during initial oral screening can improve the chances of patient's survival. Reports suggest that socio-economic factors, lack of public awareness and delays from primary health care centers are few of the major parameters that contribute to patient's mortality and morbidity. Conventional technique of visual examination of the oral lesion can effectively monitor patient mortality when exposed to risk factors. However, several disadvantages limit the clinical utility of this technique. Thus, screening aids that efficiently differentiate between a benign and malignant lesion as well as deliver information about early OSCC can ameliorate the complications associated with oral cancer diagnosis. Recent advances in optical imaging systems, such as tissue-fluorescence imaging and optical coherence tomography have been proved to be considerably efficient. Additionally, extensive research has been directed towards nanoparticle-based immunosensors, DNA analysis, and salivary proteomics. However, lack of proper clinical trials and correlation with biopsy result hinder the usage of these screening techniques in clinics. In this review, we highlight the importance of early diagnosis of oral cancer as well as discuss about the effectiveness and limitations of the recent diagnostic aids. It can be stated that public awareness regarding routine oral examination and employing screening methods that are non-invasive, robust, and economic, would enhance early stage diagnosis of oral cancer and have a positive impact on patient's survival.


Assuntos
Testes Diagnósticos de Rotina/métodos , Neoplasias Bucais/diagnóstico , Biomarcadores Tumorais , Humanos , Programas de Rastreamento , Exame Físico
5.
Environ Sci Pollut Res Int ; 26(21): 21394-21403, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31124068

RESUMO

The use of P25 TiO2 NPs in consumer products, their release, and environmental accumulation will have harmful effects on the coastal ecosystems. The sensitivity to TiO2 NPs may vary depending on the structural property and physiological mechanism of algal species. Therefore, the present study investigates the differences in sensitivity of two marine algae, Dunaliella salina and Chlorella sp., towards P25 TiO2 NPs. Among the two species, Chlorella sp. was more sensitive to TiO2 NPs than Dunaliella salina. The different working concentrations of TiO2 NPs, 0.1, 1, and 10 mg L-1, were selected based on the EC50 value. The EC50 value of TiO2 NPs for Dunaliella salina was found to be 1.8 and 13.3 mg L-1 under UV-A and dark conditions, respectively. The EC50 value of TiO2 NPs for Chlorella sp. was found to be 1.6 and 5.0 mg L-1 under UV-A and dark conditions, respectively. The decrease in cell viability was significantly higher for Chlorella sp. compared to Dunaliella salina at all concentrations except 0.1 mg L-1. The cellular viability data was in correlation with the oxidative stress markers such as total ROS and LPO. A concentration-dependent increase in ROS and lipid peroxidation was noted under UV-A exposure, which was higher in Chlorella sp. compared to Dunaliella salina. The decrease in the SOD activity with NP concentration was more in Dunaliella salina than Chlorella sp. under both conditions, whereas Chlorella sp. showed increased CAT activity with increasing concentration. The uptake of TiO2 NPs was more in Chlorella sp. than Dunaliella salina.


Assuntos
Microalgas/fisiologia , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Chlorella , Ecossistema , Peroxidação de Lipídeos , Estresse Oxidativo
6.
J Environ Manage ; 236: 93-99, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30716695

RESUMO

The occurrence of various antibiotics in natural waters poses an emerging environmental concern. Tetracycline (TC) is a frequently used antibiotic in human therapy, veterinary industry, and agricultural sectors. In the current study, TC removal from aqueous solutions was studied using binary Nickel/nano zero valent iron particles (NiFe nano particles) and in-situ NiFe nanoparticles coated sand (IS-NiFe). Removal of TC using bimetallic NiFe particles was optimized with help of response surface methodology (RSM). Using the optimized parameters (concentration of TC: 20 mg/L; NiFe dose: 120 mg/L; time of interaction: 90 min), 99.43 ±â€¯0.98% removal of TC was noted. Further, IS-NiFe was packed in the column reactors and effects of different parameters like flow rate (1-3 mL/min), bed height (3-10 cm) and inlet TC concentration (20-60 mg/L) on breakthrough characteristics were examined. Under the optimized conditions the removal capacity in the column reactor was 1198 ±â€¯40.2 mg/g using IS-NiFe. The column kinetic data were successfully fitted with Adams- Bohart and Thomas models. TC removal efficiency of IS-NiFe in column reactors was tested with TC (20 mg/L) spiked lake water, ground water, and tap water and the removal capacity was noted to be 698.55 ±â€¯11.21, 764.17 ±â€¯6.78, and 801.7 ±â€¯13.26 mg/g respectively.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Adsorção , Antibacterianos , Dióxido de Silício , Tetraciclina
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 202: 346-351, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-29800899

RESUMO

There is always a substantial effort to develop a point of care detection for a severe and acute disease like dengue. In this work, we have described the detection of serotype-specific dengue virus using multicolor triangular silver nanoparticles (TAg) which could be a potential diagnosis method to distinguish between serotype. Functionalized TAg was prepared with polyA10 DNA through pH-mediated process. Further, it was characterized with Transmission Electron Microscopy (TEM), Ultra Visible-visible spectroscopy (UV-vis) and gel electrophoresis and its stability towards NaCl concentration. The colorimetric detection was carried out based on the interaction of TAg-DNA probe with specific complimentary strand which was designed to form a network assembly between DNA probes and sample RNA. The hybridization process was enhanced in presence of NaCl (0.4 M) which makes the hybridization process more stable over probe compared to un-hybridization. Therefore a simple and effective colorimetric method was developed to detect the different dengue serotype RNA with high sensitivity and specificity.


Assuntos
DNA/química , Vírus da Dengue/isolamento & purificação , Nanopartículas Metálicas/química , Sorogrupo , Prata/química , Nanopartículas Metálicas/ultraestrutura , Reação em Cadeia da Polimerase , Cloreto de Sódio/química , Espectrofotometria Ultravioleta
8.
Environ Sci Pollut Res Int ; 24(31): 24187-24200, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28887611

RESUMO

Although the toxicological impact of metal oxide nanoparticles has been studied for the last few decades on aquatic organisms, the exact mechanism of action is still unclear. The fate, behavior, and biological activity of nanoparticles are dependent on physicochemical factors like size, shape, surface area, and stability in the medium. This study deals with the effect of nano and bulk CeO2 particles on marine microcrustacean, Artemia salina. The primary size was found to be 15 ± 3.5 and 582 ± 50 nm for nano and bulk CeO2 (TEM), respectively. The colloidal stability and sedimentation assays showed rapid aggregation of bulk particles in seawater. Both the sizes of CeO2 particles inhibited the hatching rate of brine shrimp cyst. Nano CeO2 was found to be more toxic to A. salina (48 h LC50 38.0 mg/L) when compared to bulk CeO2 (48 h LC50 92.2 mg/L). Nano CeO2-treated A. salina showed higher oxidative stress (ROS) than those treated with the bulk form. The reduction in the antioxidant activity indicated an increase in oxidative stress in the cells. Higher acetylcholinesterase activity (AChE) was observed upon exposure to nano and bulk CeO2 particles. The uptake and accumulation of CeO2 particles were increased with respect to the concentration and particle size. Thus, the above results revealed that nano CeO2 was more lethal to A. salina as compared to bulk particles.


Assuntos
Artemia/efeitos dos fármacos , Cério/toxicidade , Nanopartículas Metálicas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Artemia/metabolismo , Cério/metabolismo , Tamanho da Partícula , Poluentes Químicos da Água/metabolismo
9.
Biodegradation ; 24(6): 829-42, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23494520

RESUMO

In the current study, indigenous bacterial isolates Bacillus subtilis VITSUKMW1 and Escherichia coli VITSUKMW3 from a chromite mine were adapted to 100 mg L(-1) of Cr(VI). The phase contrast and scanning electron microscopic images showed increase in the length of adapted E. coli cells and chain formation in case of adapted B. subtilis. The presence of chromium on the surface of the bacteria was confirmed by energy dispersive X-ray spectroscopy (EDX), which was also supported by the conspicuous Cr-O peaks in FTIR spectra. The transmission electron microscopic (TEM) images of adapted E. coli and B. subtilis showed the presence of intact cells with Cr accumulated inside the bacteria. The TEM-EDX confirmed the internalization of Cr(VI) in the adapted cells. The specific growth rate and Cr(VI) reduction capacity was significantly higher in adapted B. subtilis compared to that of adapted E. coli. To study the possible role of Cr(VI) toxicity affecting the Cr(VI) reduction capacity, the definite assays for the released reactive oxygen species (ROS) and ROS scavenging enzymes (SOD and GSH) were carried out. The decreased ROS production as well as SOD and GSH release observed in adapted B. subtilis compared to the adapted E. coli corroborated well with its higher specific growth rate and increased Cr(VI) reduction capacity.


Assuntos
Adaptação Fisiológica , Bacillus subtilis/fisiologia , Compostos de Cromo/isolamento & purificação , Escherichia coli/isolamento & purificação , Escherichia coli/fisiologia , Mineração , Estresse Fisiológico , Bacillus subtilis/citologia , Bacillus subtilis/isolamento & purificação , Bacillus subtilis/ultraestrutura , Biodegradação Ambiental , Cromo/isolamento & purificação , Escherichia coli/citologia , Escherichia coli/ultraestrutura , Glutationa/metabolismo , Oxirredução , Estresse Oxidativo , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxido Dismutase/metabolismo
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