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1.
J Colloid Interface Sci ; 627: 956-968, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35901574

RESUMO

Carbon dots (C-dots) developed from beetroot is used for the rational design of cadmium sulphide based heterojunction photocatalysts (C-dots@CdS) using hydrothermal technique. The crystal structure, phase, morphology and optical characteristics of the synthesised materials are determined using X-ray diffraction (XRD), High resolution transmission electron microscopy (HR-TEM), Field emission scanning electron microscopy (FESEM), Energy dispersive X-ray analysis (EDAX), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, UV-Visible diffuse reflectance spectroscopy (UV-DRS), photoluminescence spectroscopy (PL spectroscopy), BET adsorption, X-ray photoelectron spectroscopy (XPS) and electrochemical studies. Using C-dots@CdS catalytic system, a superior photocatalytic activity relative to the undecorated CdS is observed. Among the C-dots@CdS samples, the CdS loaded with 6 wt% of C-dots exhibited enhanced hydrogen evolution rate compared with other samples considered for the study. CdS nanospheres modified with C-dots (6 wt%) resulted in the photocatalytic hydrogen evolution rate of 1582 µmolg-1 against 849 µmolg-1 evolution rate obtained for CdS nanospheres within 3 h. In spite of being 0D/0D type nano-heteroarchitecture, C-dots@CdS system obtained an apparent quantum yield of 6.37 % for the catalytic dosage of 20 mg under the irradiation of visible light. CdS in the C-dots@CdS system serves as the light harvester while C-dots with discernible edges can maintain the continuous supply of photo-excited charge carriers and hence can reduce the charge-carrier recombination. Further, the photodegradation of crystal violet dye using the optimised dosage of C-dots@CdS-6 exhibited an efficiency of 97.3 % in 120 min of visible light irradiation under neutral conditions. The detailed kinetic study reveals that the mechanism of photodegradation of crystal violet dye using C-dots@CdS system can be described using pseudo-second-order kinetics. The presence of oxygen rich hydrophilic surface functionalities of C-dots, the formation of near-surface heterojunction and the suitable band structure of C-dots@CdS system leading to the optimum charge carrier separation kinetics can be attributed to the enhanced photocatalytic performance. This work offers a promising strategy to develop bio-derived C-dots based heterojunction photocatalyst to address the burgeoning energy and environmental demands.


Assuntos
Carbono , Nanosferas , Cádmio , Compostos de Cádmio , Compostos Inorgânicos de Carbono , Violeta Genciana , Hidrogênio , Luz , Oxigênio , Sulfetos
2.
Nanomaterials (Basel) ; 12(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35630949

RESUMO

The chemical content of plant excerpts can be efficiently employed to reduce the metal ions to nanoparticles in the one-pot green production method. Here, green production of silver nanoparticles (AC-AgNPs) is performed by means of Allium cepa var. Aggregatum (shallot) extract as a stabilizer and reducer. The shape, size, and morphology of resultant AC-AgNPs are examined by optical spectroscopy analysis such as UV for nucleation and coalescence processes of the AC-AgNPs. Through FTIR functional group is determined and through DLS size is defined, it was confirmed that metallic AgNPs were successfully synthesized through the green synthesis route, and these results agreed well with the results obtained in the XRD pattern along with TEM spectroscopy, where the TEM images confirm the formation of sphere-like nanostructures along with SAED analysis. The chemical characterization is performed with XPS; the obtained molecular species in the materials are determined from the energy profile. Antioxidant activity of AC-AgNPs versus DPPH substrate is carried out. Antibacterial activity is well established against Gram-negative and Gram-positive organisms. Cell viability is accomplished, followed by an MTT assay, and a cytotoxicity assay of AC-AgNPs on MCF-7 cell lines is also carried out. Highlights: (1). This study highlights the eco-friendly synthesis of silver nanoparticles from Allium cepa var. Aggregatum Natural Extract. (2). The synthesized AC-AgNPs were characterized by UV-VIS, FT-IR, XRD, TEM, and XPS. (3). The synthesized nanoparticles were well dispersed in nature and the size range of 35 ± 8 nm. (4). The anti-candidal activity of biosynthesized silver nanoparticles was evaluated against the following Gram-Negative organisms: Escherichia coli (E. coli), and the following Gram-positive organisms: Staphylococcus aureus strains. The biosynthesized AC-AgNPs showed enhanced antiseptic features anti both Gram-positive and negative organisms. (5). Besides, the in vitro cytotoxic outcomes of AC-AgNPs were assessed versus MCF-7 cancerous cells, and the reduction in the feasibility of cancer cells was established via MTT assay, which suggests potential biomedical applications.

3.
Diabetes Ther ; 13(4): 747-759, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35286607

RESUMO

INTRODUCTION: In this ORION study subgroup analysis, the safety and effectiveness of insulin glargine 300 U/mL (Gla-300) was evaluated in people from the South Asia region with type 2 diabetes mellitus (T2DM) before, during, and after Ramadan, in a real-world setting. METHODS: The ORION study was a real-world, prospective, observational, non-comparative study conducted across 11 countries. The current subgroup analysis included participants from the South Asia region (India and Pakistan) who fasted during Ramadan. The primary endpoint was the percentage of participants experiencing ≥ 1 event of severe and/or symptomatic documented hypoglycemia with self-monitored plasma glucose (SMPG) ≤ 70 mg/dL during Ramadan. Secondary endpoints analyzed were changes in glycated hemoglobin (HbA1c), fasting plasma glucose (FPG), SMPG, insulin dose, and adverse events (AEs). RESULTS: This subgroup analysis included 106 participants from the South Asia region with mean (standard deviation) age of 51.3 (10.9) years and mean number of 29.8 (4.0) fasting days. The number of severe and/or symptomatic documented hypoglycemia events was low in the pre-Ramadan (SMPG ≤ 70 mg/dL: 1 event [0.9%]; SMPG < 54 mg/dL: 1 event [0.9%]) and Ramadan periods (SMPG ≤ 70 mg/dL: 1 event [0.9%]; SMPG < 54 mg/dL: 0 events), and none in the post-Ramadan period. One participant reported severe hypoglycemia (any time of the day: nocturnal or daytime) throughout the pre-Ramadan period. A reduction in HbA1c and FPG levels was seen during the pre- to post-Ramadan period; however, a slight increase in SMPG levels was reported during this same period. Gla-300 daily dose was reduced from 21.6 (9.6) U to 20.2 (8.9) U during the pre-Ramadan to Ramadan period. The incidence of AEs was 1.9%. CONCLUSIONS: The real-world data from the ORION study indicate that Gla-300 is effective, with low risk of hypoglycemia, for the management of T2DM during Ramadan in the South Asian population. TRIAL REGISTRATION: CTRI/2019/02/017636.

4.
Drug Dev Ind Pharm ; 46(8): 1334-1344, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32598194

RESUMO

The present investigation focused mainly on the development of aceclofenac (AF) loaded transfersomal gel (AF-TG) to minimize the frequency of oral dosing during the treatment of osteoarthritis, rheumatoid arthritis and ankylosing spondylitis. AF-loaded transfersomes (AF-TS) were prepared by using the film hydration method. The effect of drug loading, pH of hydration medium, edge activator (EA) and lipid concentration on the properties of the AF-TS were studied and optimized. Optimized AF-TS converted into AF-TG by the addition of carbopol 934. Morphology and compatibility studies of AF-TS were observed with scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). AT-TG formulation was evaluated further for ex vivo skin permeation studies compared with marketed Hifenac 30 g gel. Optimized AF-TS showed vesicle size, PDI, and zeta potential of 111.1 ± 3.2 nm, 0.19 ± 0.02, and -29.6 ± 1.2 mV, respectively. Entrapment efficiency of 74.1 ± 1.8% with pH 5.8 phosphate buffer as a hydration medium and 17.1 ± 0.9 elasticity at 0.15%w/v EA and 1%w/v lipid concentration were observed. SEM and DSC studies revealed the spherical shape and no incompatibilities in the AF-TS formulation. The permeability of the AF from AF-TG was enhanced by 14-folds with similar rheological properties compared with marketed gel. Overall, TG containing AF was superior to marketed AF gel formulation for enhanced skin delivery. Therefore, TS and TG formulation could be considered as an alternative delivery approach for the enhanced transdermal application of AF.


Assuntos
Lipídeos , Pele , Administração Cutânea , Diclofenaco/análogos & derivados , Diclofenaco/química , Portadores de Fármacos
7.
Colloids Surf B Biointerfaces ; 173: 9-17, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30261347

RESUMO

In the present study, an attempt has been made to explore the antifouling potential of bioactive compound isolated from sponge associated bacterium Halobacillus kuroshimensis SNSAB01. The crude extract of SNSAB01 strongly inhibited the growth of fouling bacterial strains with least minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The bioactive compound was characterized through FT-IR, HPLC, GCMS and NMR predicted as 'pyrrolo". From the mass spectral library, structure was elucidated as pyrrolo [1, 2-a] pyrazine-1, 4-dione, hexahydro. The in silico studies provided encouraging docking scores with two interactions by GLN 200 and GLU 304. The extract inhibited 89% diatom adhesion at 350 µg/ml concentration against Amphora sp. An EC50 value of 150 µg/ml for 50% inhibition of byssal thread of Perna viridis and LC50 was found to be 500 µg/ml. The LC50/EC50 ratio of 3.0 indicated nontoxic to nature. The result suggested that pyrrolo[1,2-a]pyrazine-1,4-dione can be used for antifouling coating.


Assuntos
Anti-Infecciosos/farmacologia , Bivalves/efeitos dos fármacos , Diatomáceas/efeitos dos fármacos , Halobacillus/química , Pirazinas/farmacologia , Pirróis/farmacologia , Acetilglucosamina/análogos & derivados , Acetilglucosamina/metabolismo , Animais , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Sítios de Ligação , Bivalves/crescimento & desenvolvimento , Misturas Complexas/química , Diatomáceas/crescimento & desenvolvimento , Matriz Extracelular/química , Halobacillus/classificação , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Filogenia , Poríferos/microbiologia , Pirazinas/química , Pirazinas/isolamento & purificação , Pirróis/química , Pirróis/isolamento & purificação , Simbiose/fisiologia
8.
Int J Biol Macromol ; 115: 696-710, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29702164

RESUMO

Marine ecosystem comprises of microorganisms, plants, invertebrates and vertebrates which were rich source of diverse antimicrobial products, which were structurally unique belonging to a known class of macromolecules like peptides, terpenes, alkaloids and proteins, etc. Natural macromolecules from marine ecological niches are a promising source of antibacterial agents against several drug resistant strains of pathogenic microorganisms; whereas rest of the metabolites were derived from marine flora and fauna while some arise from microbes associated with living organisms. >30,000 natural macromolecules have been identified and reported from marine organisms, however only few macromolecules are being explored and validated. The discovery of marine antibacterial macromolecules plays a significant part in the field of drug discovery and biomedical research. Despite the fact that literatures were documented on the antifungal, antiviral, antimalarial and anticancer properties, this review exclusively highlights the different antibacterial natural macromolecules from marine sources like bacteria, fungi, sponge, algae, bryozoans, tunicates, corals, cnidarians, arthropods and echinoderm along with their mode of action.


Assuntos
Antibacterianos , Organismos Aquáticos/química , Substâncias Macromoleculares , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Humanos , Substâncias Macromoleculares/isolamento & purificação , Substâncias Macromoleculares/farmacologia
9.
ACS Appl Bio Mater ; 1(5): 1741-1757, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34996223

RESUMO

A new era has begun in which pathogens have become useful scaffolds for nanotechnology applications. In this research/study, an attempt has been made to generate an empty cargo-like architecture from a plant pathogenic virus named Squash leaf curl China virus (SLCCNV). In this approach, SLCCNV coat protein monomers are obtained efficiently by using a yeast Pichia pastoris expression system. Further, dialysis of purified SLCCNV-CP monomers against various pH modified (5-10) disassembly and assembly buffers produced a self-assembled "Nanocargo"-like architecture, which also exhibited an ability to encapsulate magnetic nanoparticles in vitro. Bioinformatics tools were also utilized to predict the possible self-assembly kinetics and bioconjugation sites of coat protein monomers. Significantly, an in vitro biocompatibility study using SLCCNV-Nanocargo particles showed low toxicity to the cells, which eventually proved as a potential nanobiomaterial for biomedical applications.

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