Effect Of Platinum Nanoparticles Research Articles

Effect of platinum nanoparticles on rabbit spermatozoa motility and viability

Male reproductive health is becoming a frequently asked question nowadays. Spermatozoa can be highly sensitive to various substances found in the environment. With the accretive usage of nanoparticles in technology and medicine, nanoparticles may also pose as potential environmental contaminants. Platinum nanoparticles are increasingly used in medicine, mainly for cancer treatment. The aim of this study was to investigate the effect of platinum nanoparticles on the motility and viability of rabbit spermatozoa in-vitro. Rabbit semen (n = 5) was cultured with solutions with different concentrations of platinum nanoparticles (control group or CON = only 0.9% NaCl; experimental groups D = 62.5 µg/ml, E = 31.25 µg/ml, F = 15.63 µg/ml, G = 7.81 µg/ml, H = 3.91 µg/ml, I = 1.95 µg/ml, J = 0.98 µg/ml, K = 0.49 µg/ml, and L = 0.24 µg/ml platinum nanoparticles) at time intervals of 0, 2, 4, 6, 9 and 24 hours. Selected parameters were analysed by computer-assisted sperm analyzer (CASA) technology – total motility (MOT, %), progressive motility (PRO, %), curvilinear velocity (VCL, µm/s) and viability (metabolic activity) of spermatozoa using the MTT test. Platinum nanoparticles negatively affected spermatozoa motility, progressive motility, and curvilinear velocity at almost all assessed time intervals, mainly at the highest used concentrations. The initial time interval shows a slight but statistically significant increase in MOT and PRO. Spermatozoa viability was not significantly affected, according to the results of this experiment. It was shown that the effect of platinum nanoparticles is time and dose-dependent. However, further analyses are needed to draw complete conclusions.

Effect of platinum nanoparticles on the chemoresistive gas sensitive properties of the ZnO/Pt composite

The ZnO/xPt nanocomposites (x = 0.5, 1, 2, 3 mol.%) obtained by the solvothermal method were used for microextrusion printing of films onto special Al2O3/Pt sensors. The obtained powders have a hexagonal crystal lattice and consist of zinc oxide flowers (152–185 nm) assembled from rods (53–78 nm), and platinum nanoparticles of 2–5 nm are on their surface. Using XPS, platinum was found to be partially in an oxidized state (as PtO and PtO2). Using impedance spectroscopy, the electrophysical characteristics of the samples were studied: temperature and frequency dependences of conductivity, which have linear and degree character, respectively. The chemoresistive gas-sensitive properties to CO, H2, C6H6, NO2, NH3, СH4, С3H6O and C2H5OH at 200–300 °C has been studied. The highest response was observed at 225 °C for ethanol. It was shown that by increasing platinum content from 0.5 to 3 mol.% Pt a significant increase in response (Rair/R) to 100 ppm ethanol from 17 to 47, but the process kinetics deteriorated. The detection mechanism of ethanol has been studied in detail, as well as the effect of humidity on the received signal. Using the principal component method, it is shown that the sensors can be used for the selective separation of a wide group of gases.

Effect of Platinum Nanoparticles on the Structure of Protein Molecules and Regulation of the Tone of Brain Vessels in Experimental Animals.

The effects of platinum nanoparticles on the morphological structures of the solid phase of blood serum and the tone of cerebral microvessels as indicators of the dynamics of homeostasis were studied on outbred albino male rats (n=40) weighing 300-350 g. Platinum nanoparticles were injected to experimental animals in 1 ml of physiological saline. For systemic BP measurements and blood sampling, the femoral artery was isolated and catheterized. The study of solid phase structures of blood serum was conducted by the method of cuneiform dehydration. The results showed that injection of platinum nanoparticles significantly affected the body of experimental animals.

The Effect of Platinum Nanoparticles and Silicone Monomers for High Gas Permeable Materials

The Effect of Platinum Nanoparticles and Silicone Monomers for High Gas Permeable Materials

Effect of platinum nanoparticles on cell death induced by ultrasound in human lymphoma U937 cells

In this study, we report on the potential use of platinum nanoparticles (Pt-NPs), a superoxide dismutase (SOD)/catalase mimetic antioxidant, in combination with 1MHz ultrasound (US) at an intensity of 0.4W/cm2, 10% duty factor, 100Hz PRF, for 2min. Apoptosis induction was assessed by DNA fragmentation assay, cell cycle analysis and Annexin V-FITC/PI staining. Cell killing was confirmed by cell counting and microscopic examination. The mitochondrial and Ca2+-dependent pathways were investigated. Caspase-8 expression and autophagy-related proteins were detected by spectrophotometry and western blot analysis, respectively. Intracellular reactive oxygen species (ROS) elevation was detected by flow cytometry, while extracellular free radical formation was assessed by electron paramagnetic resonance spin trapping spectrometry. The results showed that Pt-NPs exerted differential effects depending on their internalization. Pt-NPs functioned as potent free radical scavengers when added immediately before sonication while pre-treatment with Pt-NPs suppressed the induction of apoptosis as well as autophagy (AP), and resulted in enhanced cell killing. Dead cells displayed the features of pyknosis. The exact mode of cell death is still unclear. In conclusion, the results indicate that US-induced AP may contribute to cell survival post sonication. To our knowledge this is the first study to discuss autophagy as a pro-survival pathway in the context of US. The combination of Pt-NPs and US might be effective in cancer eradication.

Effect of Platinum Nanoparticles on Biological Activity of Humus-Accumulated Horizons

The exponential growth of nanoparticle-containing goods and waste of the recent years will lead unavoidably to nanomaterials entering environment, generating in local biota and abiotic environment, and potentially transmitting to man. Aerial and water transmission of nanoparticles eventually will cause its generation in soil and further transmission to plants and animals via food chains.

A double gate DNA FET based on solution processed ZnO nano layers for high sensitivity and low cost oligonucleotide hybridization detection

In this paper, an oligonucleotide hybridization detection sensor is presented. The sensor uses field effect transistor (FET) devices to sense the surface charge, amplify it and produce a detectable output signal. With the FET device, hybridization can be detected at lower volumes and concentrations. The FET device is based on solution processed ZnO nano layers as the semiconductor channel. Since the design uses a low cost fabrication procedure, the sensors can be disposed economically after successful completion of the measurements. Furthermore the presented ZnO FET device benefits from double gate advantages. The bottom gate is used to provide the required initial bias conduction channel while the top gate is used to modulate the threshold voltage using the surface charge variations. The effect of platinum nano particles on thiolated DNA probe assembly at the sensor surface is also investigated in this paper. The presented concept is evaluated using a probe station instrument. The input–output transfer curve of the FET is extracted for different surface configurations including DNA probe, DNA probe hybridized with a match (complementary) target and DNA probe coated with un-match DNA sequence. It is shown that the hybridization can be identified with threshold voltage shifts of the transfer curve. It is also observed that the nano platinum linkers increase the sensor’s sensitivity.

Enhanced activity of chaperonin GroEL in the presence of platinum nanoparticles

The chaperonin protein GroEL was mixed with varying concentrations of K2PtCl4 followed by a 20-fold concentration of sodium borohydride to afford GroEL–platinum nanoparticle complexes in a ratio of between 1:25 and 1:2,000. Typical colour change, from colourless or pale yellow to brown, occurred that was dependent on the amount of platinum present. These complexes were characterised by UV/Vis, inductively coupled plasma optical emission spectroscopy, Fourier transform infra red, transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy. TEM analysis revealed that the size of nanoparticles increased as the molar ratio of platinum to GroEL increased with an average size diameter of 1.72–3.5 nm generated with GroEL–platinum molar ratios of 1:125–1:2,000. Fourier-transform infrared spectroscopy (FTIR) spectra showed no distinct changes in the structure of GroEL but confirmed that the nanoparticles were attached to the protein. The effect of platinum nanoparticles on the ATPase activity of GroEL showed an activity of 5.60 μmol min−1 ml−1 (87 % increase over a control) at the molar ratio of GroEL–platinum nanoparticles of 1:25.

Ferroxidase activity of apoferritin is increased in the presence of platinum nanoparticles

The ferroxidase activity of horse spleen apoferritin (HSAF) is increased by nine-fold in the presence of platinum nanoparticles. HSAF was mixed with varying concentrations of K2PtCl4 followed by a 20-fold concentration of sodium borohydride to afford Pt:HSAF nanoparticle complexes in a ratio of between 1:250 and 1:4000. Typical colour changes, from colourless or pale yellow to brown, occurred that were dependent on the amount of platinum present. These complexes were characterized by UV/vis, inductively coupled plasma optical emission spectroscopy, Fourier transform infrared, transmission electron microscopy and energy dispersive x-ray spectroscopy. Transmission electron microscopy analysis revealed that the size of nanoparticles increased as the molar ratio of platinum to HSAF increased with an average size diameter of 2–6 nm generated with HSAF:platinum molar ratios of 1:250–1:4000. Fourier transform infrared spectroscopy (FTIR) spectra showed no distinct changes in the structure of HSAF but confirmed that the nanoparticles were attached to the protein. The effect of platinum nanoparticles on the ferroxidase activity of HSAF showed a specific activity of 360 ρmol min−1 mg−1, (nine-fold increase over the control) at the molar ratio of HSAF:platinum nanoparticles of 1:1000.

SOD/catalase mimetic platinum nanoparticles inhibit heat-induced apoptosis in human lymphoma U937 and HH cells

Platinum nanoparticles (Pt-NPs) are known to possess anti-tumouric activity and the ability to scavenge superoxides and peroxides indicating that they can act as superoxide dismutase (SOD)/catalase mimetics. These potentials seem useful in the protection and/or amelioration of oxidative stress-associated pathologies, but, when they are combined with a therapeutic modality that depends upon the mediation of reactive oxygen species in cell killing induction, the effect of Pt-NPs might be questionable. Here, the effects of polyacrylic acid-capped Pt-NPs (nano-Pts) on hyperthermia (HT)-induced apoptosis and the underlying molecular mechanisms were investigated in human myelomonocytic lymphoma U937 and human cutaneous T-cell lymphoma HH cells. The results showed that the pre-treatment with nano-Pts significantly inhibited HT-induced apoptosis in a dose-dependent manner. Superoxide, but not peroxides, was suppressed to varying extents. All pathways involved in apoptosis execution were also negatively affected. The results reveal that the combination of nano-Pts and HT could result in HT-desensitization.