Studies find $1 test using gold nanoparticles outperforms PSA screen for prostate cancer

A test that costs less than a $1 and yields results in minutes has been shown in newly published studies to be more sensitive and more exact than the current standard test for early-stage prostate cancer. The simple test developed by University of Central Florida scientist Qun "Treen" Huo holds the promise of earlier detection of one of the deadliest cancers among men. It would also reduce the number of unnecessary and invasive biopsies stemming from the less precise PSA test that's now used. Dr. Qun Dr. Qun "Treen" Huo of UCF's NanoScience Technology Center has developed a prostate cancer test using gold nanoparticles. Pilot studies found it to be more accurate than the standard PSA test. "It's fantastic," said Dr. Inoel Rivera, a urologic oncologist at Florida Hospital Cancer Institute, which collaborated with Huo on the recent pilot studies. "It's a simple test. It's much better than the test we have right now, which is the PSA, and it's cost-effective." When a cancerous tumor begins to develop, the body mobilizes to produce antibodies. Huo's test detects that immune response using gold nanoparticles about 10,000 times smaller than a freckle. When a few drops of blood serum from a finger prick are mixed with the gold nanoparticles, certain cancer biomarkers cling to the surface of the tiny particles, increasing their size and causing them to clump together. Among researchers, gold nanoparticles are known for their extraordinary efficiency at absorbing and scattering light. Huo and her team at UCF's NanoScience Technology Center developed a technique known as nanoparticle-enabled dynamic light scattering assay (NanoDLSay) to measure the size of the particles by analyzing the light they throw off. That size reveals whether a patient has prostate cancer and how advanced it may be. And although it uses gold, the test is cheap. A small bottle of nanoparticles suspended in water costs about $250, and contains enough for about 2,500 tests. "What's different and unique about our technique is it's a very simple process, and the material required for the test is less than $1," Huo said. "And because it's low-cost, we're hoping most people can have this test in their doctor's office. If we can catch this cancer in its early stages, the impact is going to be big." After lung cancer, prostate cancer is the second-leading killer cancer among men, with more than 240,000 new diagnoses and 28,000 deaths every year. The most commonly used screening tool is the PSA, but it produces so many false-positive results - leading to painful biopsies and extreme treatments - that one of its discoverers recently called it "hardly more effective than a coin toss." Pilot studies found Huo's technique is significantly more exact. The test determines with 90 to 95 percent confidence that the result is not false-positive. When it comes to false-negatives, there is 50 percent confidence - not ideal, but still significantly higher than the PSA's 20 percent - and Huo is working to improve that number. The results of the pilot studies were published earlier this month in . Huo is also scheduled to present her findings in June at the TechConnect World Innovation Summit & Expo in suburban Washington, D.C. Huo's team is pursuing more extensive clinical validation studies with Florida Hospital and others, including the VA Medical Center Orlando. She hopes to complete major clinical trials and see the test being used by physicians in two to three years. Huo also is researching her technique's effectiveness as a screening tool for other tumors. "Potentially, we could have a universal screening test for cancer," she said. "Our vision is to develop an array of blood tests for early detection and diagnosis of all major cancer types, and these blood tests are all based on the same technique and same procedure." (Also check out our on this research: "A quick and simple blood test to detect early-stage cancer")
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Femto-snapshots of reaction kinetics

Following six years’ work, an international team comprising eleven research institutions has been successful in observing precisely how light affects the outer electrons of a metallic compound and activates this compound as a catalyst. They developed their own experiment for this investigation at the Linac Coherent Light Source X-ray laser at SLAC National Accelerator Laboratory in Menlo Park, California, which provided time resolutions down to 100 femtoseconds, and the synchrotron radiation source BESSY II of Helmholtz-Zentrum Berlin. Using quantum chemical calculations, they were successful in interpreting the data and obtaining a detailed picture of the intermediates and reaction kinetics. The work, which has now been published in , could prove helpful in developing novel catalysts for chemical storage of solar energy. An ultrashort laser pulse activates iron pentacarbonyl as a catalyst An ultrashort laser pulse activates iron pentacarbonyl as a catalyst. Scientists could observe the subsequent ultrafast processes experimentally by mapping the outer orbitals with an x-ray free electron laser and interpret the obtained energy maps using quantum chemical calculations. (Illustration: SciStyle Thomas Splettstößer) All plants do it: they store solar energy in the form of carbohydrates with the help of a metallic compound. Chemically storing sunlight would also be ideal for society's energy needs. To develop this, however, we would need to better understand exactly what happens when photons strike molecules. The primary processes run on timescales of only a few hundred femtoseconds (one femtosecond = 10-15s). Now an international collaboration has been able to map the evolution of the chemical bonds in these kinds of ultrafast processes on the level of orbitals, v “We were able to determine how incident optical photons rearrange the valence electrons of a metallic carbonyl compound. The results could help to utilise these processes in the future for more efficient conversion of sunlight into chemical energy,” explains Dr. Philippe Wernet, first author of the article that has now been published in ("Orbital-specific mapping of the ligand exchange dynamics of Fe(CO)5 in solution"). Ballet of the valence electrons in iron pentacarbonyl The team carried out their measurements on iron pentacarbonyl (Fe(CO)5), a metal complex in which an iron atom is surrounded by five carbon monoxide groups. This yellow liquid is used as a primary material for synthesizing organometallic compounds and may also function as a catalyst. Fe(CO)5 has 18 valence electrons and is therefore inert like a noble gas, but can be activated by light. Photons cleave off a carbon monoxide so that the remaining Fe(CO)4 molecule only has 16 valence electrons making it a so called 16-electron catalyst. Such homogeneous catalysts can be potentially used in converting methane to methanol, for example. Fe(CO)4 is highly reactive, however, only as long as it is in the singlet state. If the molecule is instead in the triplet state, it remains inert and does not form further compounds according to the laws of quantum chemistry. The study demonstrates how atom-specific probing of the frontier-orbital interactions uniquely enables correlating quantum-chemical properties of the system with its reactivity. One year of setup, sixty hours of measurements, four years of evaluation Twenty-one researchers from eleven research institutions participated in the research project – many of them within the Helmholtz Virtual Institute “Dynamic Pathways in Multidimensional Landscapes”. Alexander Föhlisch provided the unique expertise in time resolved resonant inelastic X-ray scattering with his 2009 established institute at HZB and Potsdam University. The experiment was set up by the PhD student Kristjan Kunnus with Philippe Wernet and the team at HZB and in collaboration with Simone Techert and her group, then at the Max Planck Institute of Biophysical Chemistry in Göttingen, now DESY and Goettingen Research Campus, who also brought in the chemistry expertise and liquid jet technology. After characterization at BESSY II all was shipped for 60 hours measurement to the x-ray free-electron laser LCLS of the SLAC National Accelerator Laboratory in the USA. It involves what is known as a pump-probe scheme in which a very short laser pulse in the optical region excites the valence electrons of the molecule (pump), while soft X-ray pulses arrive a well-defined time delay in the femtosecond range later and probe the system for information. Michael Odelius’ team and his PhD student Ida Josefsson at the University of Stockholm modelled the compound and its excited states using quantum calculations over the following years. Only after these calculations were made could the data be interpreted to such a level of detail that the experimental observables could be unambiguously correlated with chemical interactions in the system. “We had created basically four-dimensional data records with new coordinates of the incident energy, transferred energy as well as the intensity for various time delay between pump and probe pulses of every hundred femtoseconds”, explains Kristjan Kunnus. Prospects The results also show the extent to which the spin states of the electrons determine whether the molecules transition to reactive states or not after being excited by the sunlight. This is essential because actually both possible spin states, in the present case, were found to be represented due to the ultrafast transitions between singlet and triplet states. The measurements are a first step toward development of multidimensional X-ray spectroscopy in order to measure chemical dynamics on pulsed X-ray sources like Free Electron Lasers or BESSY-VSR. “Now that we understand the reaction kinetics, we can control them or design a system to favour desired reactions, for example, in order to chemically store solar energy”, according to Wernet.
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Oxford Instruments Asylum Research Presents 'Piezoresponse Force Microscopy: From Theory to Advanced Applications'

Oxford Instruments Asylum Research will host a two-part webinar series on Piezoresponse Force Microscopy (PFM), May 4 and May 6, 2015. Presenters include Dr. Sergei V. Kalinin, Director at the Institute for Functional Imaging of Materials and Theme Leader at the Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, and Asylum Research President and co-founder, Dr. Roger Proksch. The first part of the webinar will be perfect for researchers who are either entirely new to PFM or who perhaps just haven’t heard about the full spectrum of existing PFM capabilities. The second part of the series will focus on new advanced capabilities and applications examples available via CNMS user program and Asylum. Single Frequency PFM scan of PZT made at 20 Hz with a Pt coated AC240 Electrilever Single Frequency PFM scan of PZT made at 20 Hz with a Pt coated AC240 Electrilever. The piezoresponse amplitude was overlaid (color) on top of the rendered topography. Domains are visible as regions of nearly constant amplitude, 7.5µm scan. Imaged with the Cypher™ AFM. “Introduction to PFM” broadcasts May 4 and will cover the basic theory of PFM and electromechanical coupling, limitations of conventional PFM methodologies, and advances in instrumentation to overcome these limitations including switching spectroscopy PFM, Dual AC™ Resonance Tracking (DART) PFM, and band excitation measurements. The May 6th webinar will follow-up with discussions on “Advanced PFM Techniques”. Kalinin and Proksch will cover the recent progress in techniques such as Band Excitation (measuring a more complete frequency response), multidimensional PFM spectroscopy, and Electrochemical Strain Microscopy. Challenges and progress in obtaining accurate d33 measurements will also be discussed. “PFM has become the technique of choice for researchers that wish to characterize the functionality of piezoelectric, ferroelectric, and multiferroic materials at the nanoscale,” said Sergei Kalinin. “The recent application of PFM techniques to energy storage and conversion materials has been a beautiful synergy for both application areas.” “Roger Proksch added, “This webinar will be an excellent resource for scientists that want to learn more about basic PFM and for those that want to delve into the advanced theory and techniques. We have learned a tremendous amount about the science of PFM through our collaboration with the global leaders in the field and are excited to share some of these results through our webinar.” Registration for “Introduction to PFM”, May 4, 2015 9:00am PDT session – (http://bit.ly/1NMlkkm) 5:00pm PDT session – (http://bit.ly/1Goh4VK) Registration for “Advanced PFM Techniques”, May 6, 2015 s 9:00am PDT session – (http://bit.ly/1NMllVw) 5:00pm PDT session – (http://bit.ly/1Goh2xa) All registrants will receive a free PFM poster.
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