ABSTRACT
This paper presents the results of several experimental methods (FT-IR spectroscopy, UV-vis spectroscopy, fluorescence microscopy (FM), Atomic Force Microscopy (AFM)) evidencing structural changes induced in extremely diluted solutions (EDS), which are prepared by an iterated process of centesimal (1:100) dilution and succussion (shaking). The iteration is repeated until an extremely high dilution is reached, so that the composition of the solution becomes identical to that of the solvent--in this case water--used to prepare it. The experimental observations reveal the presence of supramolecular aggregates hundreds of nanometres in size in EDS at ambient pressure and temperature, and in the solid state. These findings confirm the hypothesis--developed thanks to previous physico-chemical investigations--that formation of water aggregates occurs in EDS. The experimental data can be analyzed and interpreted with reference to the thermodynamics of far-from-equilibrium systems and irreversible processes.
Subject(s)
Homeopathy , Nanostructures/chemistry , Water/chemistry , Microscopy, Atomic Force , Microscopy, Fluorescence , Solutions , Temperature , ThermodynamicsABSTRACT
Phytochemicals sources have been extensively used as reducing and capping agents for synthesis of nanoparticles (NPs). However, morphology-controlled synthesis and shape/size dependent applications of these NPs still need to be explored further, and there is a need to develop a way in which particular and optimized phytochemicals result in the desired NPs in lesser time and cost with higher reproducibility rate. The present study is focused on morphology-controlled synthesis and shape/size dependent application of silver NPs based on the fractionated phytochemicals of Elaeagnus umbellata extract (EU). Unlike other approaches, in this study the reaction parameters such as time, temperature, pH, stirring speed and concentration of the precursor solutions were not altered during the optimization process. The fractionated phytochemicals were used separately for the synthesis of AgNPs, and the synthesized NPs were characterized by UV-visible, FT-IR, atomic force microscopy (AFM) and scanning electron microscopy (SEM). Our findings suggested that the constituents of the extract fractions varied with the selection of the extraction solvent, and the shape/size, bactericidal properties and toxicity of the NPs have a strong correlation with the phytochemicals of the plant extract. The fractionated phytochemicals present in the water fractions (EUW) resulted in monodispersed spherical AgNPs in the size about 40â¯nm. The NPs have significant stability in physiological conditions (i.e. temperature, pH and salt), have good antibacterial activity, and were found to be non-toxic. Furthermore, AFM and SEM analysis exposed that the NPs killed the bacteria by disturbing the cellular morphology and releasing the cellular matrix. Our results justify the use of different fractions of plant extract to obtain detail implications on shape, size, antibacterial potential and toxicity of AgNPs. This is the first step in a controllable, easy and cheap approach for the synthesis of highly stable, uniform, non-toxic and bactericidal AgNPs using five fractions of EU. The findings suggested that the synthesized NPs, particularly from EUW, could be used in pharmaceutical and homeopathic industry for the development of antibacterial medications.
Subject(s)
Metal Nanoparticles/chemistry , Silver/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Elaeagnaceae , Green Chemistry Technology , Microbial Sensitivity Tests , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Plant Extracts/chemistry , Plant Extracts/pharmacology , Spectroscopy, Fourier Transform InfraredABSTRACT
The capability of crude ethanolic extracts of certain medicinal plants like Phytolacca decandra, Gelsemium sempervirens, Hydrastis canadensis and Thuja occidentalis used as homeopathic mother tinctures in precipitating silver nanoparticles from aqueous solution of silver nitrate has been explored. Nanoparticles thus precipitated were characterized by spectroscopic, dynamic light scattering, X-ray diffraction, atomic force and transmission electron microscopic analyses. The drug-DNA interactions of silver nanoparticles were analyzed from data of circular dichroism spectroscopy and melting temperature profiles using calf thymus DNA (CT-DNA) as target. Biological activities of silver nanoparticles of different origin were then tested to evaluate their effective anti-proliferative and anti-bacterial properties, if any, by exposing them to A375 skin melanoma cells and to Escherichia coli C, respectively. Silver nanoparticles showed differences in their level of anti-cancer and anti-bacterial potentials. The nanoparticles of different origin interacted differently with CT-DNA, showing differences in their binding capacities. Particle size differences of the nanoparticles could be attributed for causing differences in their cellular entry and biological action. The ethanolic extracts of these plants had not been tested earlier for their possible efficacies in synthesizing nanoparticles from silver nitrate solution that had beneficial biological action, opening up a possibility of having therapeutic values in the management of diseases including cancer.
Subject(s)
Cell Division/drug effects , Cell Survival/drug effects , G2 Phase/drug effects , Gelsemium/chemistry , Hydrastis/chemistry , Nanoparticles/chemistry , Phytolacca dodecandra/chemistry , Silver/chemistry , Thuja/chemistry , Biphenyl Compounds/chemistry , Cell Line , Circular Dichroism , Comet Assay , DNA Damage , Escherichia coli/drug effects , Ethanol , Free Radical Scavengers/chemistry , Free Radical Scavengers/pharmacology , Microbial Sensitivity Tests , Microscopy, Atomic Force , Microscopy, Electron, Transmission , Particle Size , Picrates/chemistry , Real-Time Polymerase Chain Reaction , Silver Nitrate/chemistry , Solvents , Spectrophotometry, Ultraviolet , X-Ray DiffractionABSTRACT
Ethanolic extract of Gelsemium sempervirens (family: Loganiaceae), henceforth to be called EEGS, is used in various traditional systems of medicine. In homeopathy, EEGS is known as mother tincture of G. sempervirens, which is generally used to treat pain and respiratory ailments. We demonstrated earlier anticancer activity of crude EEGS by in vitro studies on human HeLa cells. To test the hypothesis if nanoparticle-encapsulated extract (now onwards to be called NEEGS) could enhance cellular uptake and thereby improve bioactivity, we formulated nanoparticle encapsulation based on poly (lactide-co-glycolide) (PLGA) and confirmed encapsulation by scanning electron microscopy (SEM) and atomic force microscopy. EEGS was encapsulated with 81.6% efficiency in PLGA biodegradable nanoparticle formulation and F68 (polyoxyethylene-polyoxypropylene) was used as a stabilizer. Dynamic laser light scattering and SEM indicated a particle diameter of 122.6 nm. The zeta potential of the drug-loaded nanoparticles was -14.8 mV. NEEGS was characterized for their biological activities in a skin cancer cell line A375 in vitro. NEEGS exhibited relatively rapid (30 min) and more efficient cellular uptake than their un-encapsulated counterpart (45 min). Analysis of data of apoptosis study using Annexin V-FITC, terminal transferase dUTP nick end labeling assay and DNA ladder revealed that encapsulated EEGS was more potent than their un-encapsulated counterpart in inducing apoptosis of A375 cells. Reverse transcriptase-polymerase chain reaction data of survivin, cyclin-D1, caspase-3, PCNA and p53 also corroborated well to suggest greater potentials of NEEGS as anticancer agents.