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
Cryo-electron microscopy achieves unprecedented resolution using new computational methods
24.03.2017 | DOE/Lawrence Berkeley National Laboratory
How cheetahs stay fit and healthy
24.03.2017 | Forschungsverbund Berlin e.V.
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy