Self-Assembling Gold Nanoparticles Use Light to Kill Tumor Cells

May 26, 2010

(PhysOrg.com) -- A variety of studies by numerous investigators are demonstrating that gold nanoparticles have real promise as anticancer agents. When irradiated with light, gold nanoparticles become hot quickly, hot enough to generate explosive microbubbles that will kill nearby cancer cells, a physical process known as the photothermal effect.

To boost this approach, researchers at the University of California, Los Angeles, have developed a method for creating supramolecular assemblies of that function as highly efficient photothermal agents of a size designed to optimize their delivery to tumors.

Hsien-Rong Tseng and his colleagues reported their work in the journal Angewandte Chemie International Edition. Dr. Tseng is a member of the Nanosystems Biology Cancer Center, a National Cancer Institute Center for Cancer Nanotechnology Excellence.

To create their self-assembling supramolecular gold nanoparticles, the researchers took advantage of a pair of molecules, cyclodextrin and adamantine, that bind very tightly to each other. They first took gold nanoparticles, 2 in diameter, and decorated the nanoparticles’ surface with adamantane.They then added two other constructs: cyclodextrin attached to a biocompatible polymer known as polyethyleneimine, and adamantane linked to , another biocompatible polymer. When combined in various ratios, these three constructs quickly assemble into nanoparticles with well defined sizes ranging from 40 to 118 nanometers in diameter. Once the complexes were purified, the researchers then attached a tumor targeting molecule to the surface of the resulting supramolecular complexes.

For this study, the investigators used the 118 nanometer gold complexes and showed that when irradiated with a laser beam, the temperature of the assemblies rapidly soared above 374° C, the temperature at which explosive microbubbles form. To test how efficiently these complexes could kill , the researchers added them to brain tumor cells, irradiated them with light, and then measured how many cells had been killed within two hours. As a control, the researchers repeated the experiment with cells lacking the receptor for the targeting agent they added to the nanoparticles. Results from this experiment clearly showed that the targeted nanoparticles readily killed the targeted tumor cells but not the cells lacking the targeted receptor. Additional experiments showed that 2-nanometer gold nanoparticles were not nearly as effective as the supramolecular assemblies at killing the targeted cells.

This work, which is detailed in a paper titled, "Photothermal Effects of Supramolecularly Assembled for the Targeted Treatment of Cancer Cells," was supported in part by the NCI Alliance for Nanotechnology in Cancer, a comprehensive initiative designed to accelerate the application of nanotechnology to the prevention, diagnosis, and treatment of cancer. An abstract of this paper is available at the journal's Web site.

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KBK
1 / 5 (3) May 26, 2010
It works even better when one goes down to true separate single gold atoms. This can be done.

Alchemists have been doing it for over 6000 years.

It takes 10 months of diligence and work, work that is followed to the letter, in perfection, in order to do this separation trick. No high technology gear is required to do it.

Of course it is not mentioned that high levels of direct sunlight (artificial or otherwise) that penetrate the body's blood vessels will kill the vast majority of contaminants in the blood. Other studies and works have indicated that directly. This, for a good 20 years now.

Do you doubt, deride, and give me low marks? That would be fundamentally incorrect -ignorance and ego, at the least.

Remember, 99.99% (+!) of what is in the universe is still outside of science. The arrow of science must constantly be corrected in it's flight toward truth and understanding, as new information is encountered. Otherwise it slips into religion and dogma.. thus..ultimate peril.
KBK
1 / 5 (2) May 26, 2010
The thing to know, is that this 10 month gestation of gold to a true monatomic state, is only the beginning point in the process. Two other things must be done. Then it becomes the base 'stone' of legend.

The orbitals of the single atoms thus become superdeformed and they are also then electrochemically charged into another further state via another simple but lengthy process.

When that is done, the material is ready for testing and to do the works of legend.

In most cases, when someone thinks they are the smartest in the class, they go to a school for the smart and then find out that there is always another level or step up and they are no longer the smartest kid in the class. Happens every time. In the world of public physics, and known science, there is likewise another level. As in all things that are stressed to a human limit, other things come into play.

One of the greater barriers in getting there becomes a need for expanded psychology, not linear-logic thinking capacity
KronosDeret
5 / 5 (2) May 26, 2010
and now for something completely different than crazy ramblings..

So it is possible now to combine certain nanostructures eh? Not suprising but good to know. For most of human history cancer was certain death. Now it seems we are close to killing that ugly bitch. Everyone lost someone close to cancer, thanks to this im ever more hopefull.
feynmansum
not rated yet May 26, 2010
I have to respond to KBK, I just love crackpots like this.
"not mentioned that high levels of direct sunlight (artificial or otherwise) that penetrate the body's blood vessels"
I always thought people were opaque?! haha, I better up my SPF.
"10 month gestation of gold to a true monatomic state, ... Then it becomes the base 'stone' of legend."
This is also "rich" as they say, ba-da-ta! Gestating gold? hahaha. Like its an egg in the womb! wonderful.
If you're going for transmutation, I would suggest mercury and some gamma rays myself, although KBK, maybe you should cut down on the Hg...