Measuring the temperature of nanoparticles
2010-11-30
(Press-News.org) Washington, D.C. (November 30, 2010) -- One of the holy grails of nanotechnology in medicine is to control individual structures and processes inside a cell. Nanoparticles are well suited for this purpose because of their small size; they can also be engineered for specific intracellular tasks. When nanoparticles are excited by radio-frequency (RF) electromagnetic fields, interesting effects may occur. For example, the cell nucleus could get damaged inducing cell death; DNA might melt; or protein aggregates might get dispersed.
Some of these effects may be due to the localized heating produced by each tiny nanoparticle. Yet, such local heating, which could mean a difference of a few degrees Celsius across a few molecules, cannot be explained easily by heat-transfer theories. However, the existence of local heating cannot be dismissed either, because it's difficult to measure the temperature near these tiny heat sources.
Scientists at Rensselaer Polytechnic Institute have developed a new technique for probing the temperature rise in the vicinity of RF-actuated nanoparticles using fluorescent quantum dots as temperature sensors. The results are published in the Journal of Applied Physics.
Amit Gupta and colleagues found that when the nanoparticles were excited by an RF field the measured temperature rise was the same regardless of whether the sensors were simply mixed with the nanoparticles or covalently bonded to them. "This proximity measurement is important because it shows us the limitations of RF heating, at least for the frequencies investigated in this study," says project leader Diana Borca-Tasciuc. "The ability to measure the local temperature advances our understanding of these nanoparticle-mediated processes."
INFORMATION:
The article, "Local Temperature Measurement in the Vicinity of Electromagnetically Heated Magnetite and Gold Nanoparticles" by Amit Gupta, Ravi Kane and Diana-Andra Borca-Tasciuc appears in the Journal of Applied Physics. See: http://link.aip.org/link/japiau/v108/i6/p064901/s1
Journalists may request a free PDF of this article by contacting jbardi@aip.org
ABOUT JOURNAL OF APPLIED PHYSICS
Journal of Applied Physics is the American Institute of Physics' (AIP) archival journal for significant new results in applied physics; content is published online daily, collected into two online and printed issues per month (24 issues per year). The journal publishes articles that emphasize understanding of the physics underlying modern technology, but distinguished from technology on the one side and pure physics on the other. See: http://jap.aip.org/
ABOUT AIP
The American Institute of Physics is a federation of 10 physical science societies representing more than 135,000 scientists, engineers, and educators and is one of the world's largest publishers of scientific information in the physical sciences. Offering partnership solutions for scientific societies and for similar organizations in science and engineering, AIP is a leader in the field of electronic publishing of scholarly journals. AIP publishes 12 journals (some of which are the most highly cited in their respective fields), two magazines, including its flagship publication Physics Today; and the AIP Conference Proceedings series. Its online publishing platform Scitation hosts nearly two million articles from more than 185 scholarly journals and other publications of 28 learned society publishers.
ELSE PRESS RELEASES FROM THIS DATE:
2010-11-30
Washington, D.C. (November 30, 2010) -- Quantum information processing is arguably one of the most fascinating facets of modern quantum physics.
A quantum computer operates with quantum bits (qubits) as units of information. Obeying the laws of quantum mechanics, such a computer would be capable of addressing several of the most difficult computational tasks unsolvable with present technology. In the past few decades, scientists learned to perform room-sized experiments to optically control and read out a small number of qubits.
Now, researchers in Germany have successfully ...
2010-11-30
Washington, D.C. (November 30, 2010) -- A broad review of current research on nuclear power economics has been published in the Journal of Renewable and Sustainable Energy. The report concludes that nuclear power will continue to be a viable power source but that the current fuel cycle is not sustainable. Due to uncertainty about waste management, any projection of future costs must be built on basic assumptions that are not grounded in real data.
"The goal of this study was to determine what assumptions are key to reaching conclusions about the relative costs of technologies," ...
2010-11-30
SEATTLE – The worst global economic crisis in decades has not stopped public and private donors from giving record amounts of money to health assistance for developing countries, according to a new report by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington.
The research shows that development assistance for health has grown 375% from $5.66 billion in 1990 to $26.87 billion in 2010. However, IHME's preliminary estimates show that the growth rate is slowing. Between 2004 and 2008, the period of the most dramatic increases in health funding, ...
2010-11-30
The fragile regions in mammalian genomes that are thought to play a key role in evolution go through a "birth and death" process, according to new bioinformatics research performed at the University of California, San Diego. The new work, published in the journal Genome Biology on November 30, could help researchers identify the current fragile regions in the human genome – information that may reveal how the human genome will evolve in the future.
"The genomic architecture of every species on Earth changes on the evolutionary time scale and humans are not an exception. ...
2010-11-30
VIDEO:
Dr. Daniel Kelly describes how mice without the protein PGC-1 lose the ability to exercise.
Click here for more information.
ORLANDO, Fla., November 30, 2010 – Daniel Kelly, M.D., and his colleagues at Sanford-Burnham Medical Research Institute (Sanford-Burnham) at Lake Nona have unveiled a surprising new model for studying muscle function: the couch potato mouse. While these mice maintain normal activity and body weight, they do not have the energy to exercise. In the ...
2010-11-30
BEER-SHEVA, ISRAEL, November 30, 2010 -- "Good looks" are only sometimes a positive factor in consideration for a job, according to new research from Ben-Gurion University of the Negev (BGU). In the new working paper, "Are Good-Looking People More Employable?" two economics researchers from BGU prove that a double standard exists between good looks as a positive factor in men and women.
The research involved sending 5,312 CVs (resumes) in pairs to 2,656 advertised job openings in Israel. In each pair, one CV was without a picture while the second, otherwise almost identical ...
2010-11-30
Geo-microbiologists from Arizona State University have solved a long-standing conundrum about how some photosynthetic microorganisms, endolithic cyanobacteria, bore their way into limestone, sand grains, mussel shells, coral skeletons and other substrates composed of carbonate.
According to the lead investigator, ASU professor Ferran Garcia-Pichel, the answer to the mystery of what is "at the heart of an erosive force of global proportions" is a calcium-driven pump, similar to that which we use to power our muscles.
The results of Garcia-Pichel's study "Microbial excavation ...
2010-11-30
Jerusalem, November 30, 2010 – Researchers at the Hebrew University of Jerusalem who have been examining what happens in a "model earthquake" in their laboratory have discovered that basic assumptions about friction that have been accepted for hundreds of years are just wrong. Their findings provide a new means for replicating how earth ruptures develop and possibly enabling prediction of coming severe earthquakes.
"The findings have a wide variety of implications for materials science and engineering and could help researchers understand how earthquakes occur and how ...
2010-11-30
Coping with chronic pain can affect every aspect of a person's life and cause conflict between what their mind wants to achieve and what their body allows them to do, according to research in the December issue of the Journal of Nursing and Healthcare of Chronic Illness.
Swedish researchers carried out in-depth interviews with ten people who had experienced chronic pain for between four and 32 years and were taking part in an outpatient rehabilitation programme. Nine of the patients, who ranged from 22 to 50 with an average age of 38, were unable to work because of their ...
2010-11-30
Thanks to collaborative work between scientists in Donostia-San Sebastian and the University of Kiel (Germany) it has been shown that it is possible to determine and control the number of atoms in contact between a molecule and a metal electrode of copper, at the same time as the electric current passing through the union being recorded. These results were published in the Nature Nanotechnology journal.
One of the key problems in nanotechnology is the formation of electrical contacts at an atomic scale. This demands the detailed characterisation of the current flowing ...
LAST 30 PRESS RELEASES:
[Press-News.org] Measuring the temperature of nanoparticles
