In the journal Angewandte Chemie, Eugene R. Zubarev and his team at Rice University in Houston (Texas, USA) have now introduced a new pretreatment process for gold nanorods that could accelerate their use in medical applications.
How can tiny rods of gold help to fight cancer? Cancer cells are more sensitive to temperature than healthy tissue, and this fact can be exploited through local heating of the affected parts of the body. This is where the gold nanorods come into play. They can be introduced into the cancer cells and the diseased areas irradiated with near-infrared light (photoinduced hyperthermia). The rods absorb this light very strongly and transform the light energy into heat, which they transfer to their surroundings.
Gold nanorods are normally produced in a concentrated solution of cetyl trimethylammonium bromide (CTAB) and are thus coated in a double layer of CTAB. The CTAB is only deposited onto the surface, not chemically bound. In an aqueous environment, the CTAB molecules slowly dissolve. This is problematic because CTAB is highly toxic. Simply leaving out the CTAB is no solution because without this coating the nanorods would clump together.
In order to make the rods stable as well as biocompatible, various more or less complex methods of pretreatment have been developed. However, for many of these processes, it is not known how much of the toxic CTAB remains on the nanorods. Another problem is that the pretreatment can disrupt the uptake of the nanorods into cells, which drastically reduces the success of photothermal cancer treatment.Zubarev and his co-workers have now developed a new strategy that solves these problems: they replaced the CTAB with a variant that contains a sulfur-hydrogen group, abbreviated as MTAB. With various analytical processes, the scientists have been able to prove that the CTAB on these nanorods is completely replaced with an MTAB layer. The MTAB molecules chemically bond to gold nanorods through their sulfur atoms. They bind so tightly that the layer stays in place even in an aqueous solution and the rods can even be freeze-dried. They can be stored indefinitely as a brown powder and dissolve in water again within seconds.
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201107304
Eugene R. Zubarev | Angewandte Chemie
Closing the carbon loop
08.12.2016 | University of Pittsburgh
Newly discovered bacteria-binding protein in the intestine
08.12.2016 | University of Gothenburg
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
08.12.2016 | Life Sciences
08.12.2016 | Physics and Astronomy
08.12.2016 | Materials Sciences