Platinum nanoparticles toxicity

Toxicological effects of Pt nanoparticles in cells

Nanoparticles might enter the food chain, e.g. as a contaminant on the surface of food plants. However, there is only little knowledge about their uptake into cells of the gastrointestinal tract. Therefore, it is of general interest to study the correlation between particle properties like size, shape, and crystal structure on the one hand and biological responses on the other.

Human colon carcinoma cells (HT29) chosen as a model system for the study of the uptake of Ptnanoparticles. In order to control the particle properties, Pt nanoparticles are produced on β-cyclodextrin (β-CD) by supercritical fluid reactive deposition (SFRD) in the group of M. Türk (Institut für Technische Thermodynamik und Kältetechnik). Depending on the organometallic precursors and process conditions, SFRD enables the deposition of pure and highly dispersed Pt nanoparticles with distinctly different sizes and shapes. This is illustrated in Figs. 1a-c, showing as examples a single decahedral nanoparticle with about 40 nm size, an agglomerate of very small (~5 nm) irregularly-shaped particles, and approximately 100 nm sized Pt particles with predominantly cuboctahedral shape. The cellular uptake and biological response is studied in dependence on the mean particle size, particle concentration, and time of incubation in the group of D. Marko (Institut für Angewandte Biowissenschaften, Abteilung für Lebensmittelchemie und Lebensmitteltoxikologie). A significant damage of the DNA is observed for small nanoparticles with sizes below 30 nm.

Pt nanoparticles in the cells can be directly visualized by using scanning electron microscopy (SEM) and focused ion-beam (FIB) milling HT29 cells. The cells are grown on Transwell membranes and prepared for the SEM/FIB studies by fixation, dehydration and critical-point drying. Fig. 2a shows a secondary-electron (SE) image of a single HT29 cell after 24 h Pt (1 μg/cm2) incubation. The surface of the HT29 cell is characterized by microvillis and some phagocytotic protrusions. In the backscattered-electron (BSE) image of the same cell (Fig. 2b) agglomerates of Pt particles are revealed on the cell surface (arrows). This HT29 cell was subsequently cut “slice-by-slice” with the focused Ga+ ion beam in the FIB instrument and imaged by BSE. In this way, Pt particles were found in different depths in the cell interior (cf. Fig. 2c) demonstrating cellular uptake. Moreover, as visible in Fig. 2d the presence of platinum was detected by energy-dispersive X-ray spectroscopy (EDXS).

Selected publications:

[1] J. Pelka, H. Gehrke, M. Esselen, M. Türk, M. Crone, S. Bräse, T. Muller, H. Blank, W. Send, V. Zibat, P. Brenner, R. Schneider, D. Gerthsen, D. Marko, Cellular Uptake of Platinum Nanoparticles in Human Colon Carcinoma Cells and Their Impact on Cellular Redox Systems and DNA Integrity,

See also:
ProQuest, UMI Dissertation Publishing Synthesis, characterization and optimization of platinum-alloy nanoparticle catalysts in proton exchange membrane fuel cells.
Book (ProQuest, UMI Dissertation Publishing)

Is what we see based on what we believe?

by PositiveOption

Because I believe
1 Corinthians 3:19 For the wisdom of this world is foolishness with God. For it is written, He taketh the wise in their own craftiness.
That means I see that, because the cell's nanotechnology and complexity on multiple levels is unmatched by all the engineers on the earth combined, it is a paradox if it comes from a natural cause
But Science does not they say there two ways to get a efficient design?
1.Designers apply their energy and intelligence to trial and error and create a efficient design like the motor of the space shuttle
2

It is a trust in knowlede and it's source

by PositiveOption

One who loves God will see what they believe and the ones who trust science will believe what they see
1 Corinthians 3:19 For the wisdom of this world is foolishness with God. For it is written, He taketh the wise in their own craftiness.
That means I see that, because the cell's nanotechnology and complexity on multiple levels is unmatched by all the engineers on the earth combined, it is a paradox if it comes from a natural cause
But Science does not see it that way they say there two ways to get a efficient design?

Nanotechnology is not ready . how about

by bionecr

People move some of their interest to something that could be ready sooner. Nanotechnology has been given alot of press, and that may have caused us to over look the possibilities of accupuncture. Or most people are idiots and a small percentage of us do most of the creative thinking Why havent we brought the technique of accupuncture into the 21st century. Hollow micro needles delivering anti biotics to localized areas of the body, or chemotherapy delivered into the closest cappilaries. Such a waste of accupuncturists today. What if this technique were used in areas around the lungs for tuberculosis would we have cleared up infections with less risk of creating drug esistant strains

Nanotubes Increase Solar PV Conductivity 100 Million-Fold  — Sourceable
Carbon-based nanostructures are already being used as materials in solar cells with increasing frequency, yet their ability to enhance electrical performance has thus far been hampered by limited ability to assemble orderly networks using the materials.

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