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Nanofountain Probe array formation. Credit: Ho and Espinosa

Two Northwestern University researchers believe they have developed a new dual-use tool and methods for delivering drugs and other nanoscale therapeutic materials to cells using coated nanodiamonds. The researchers, Horacio Espinosa, professor of mechanical engineering, and Dean Ho, assistant professor of mechanical and biomedical engineering, at Northwestern’s McCormick School of Engineering and Applied Science, call their tool a Nanofountain Probe

To understand the probe’s abilities, Espinosa and Ho use two analogies. First, they say it’s like a fountain pen containing an “ink” of drug-coated nanodiamonds that can then be written with. The other analogy is to a syringe - albeit a very tiny one - so small that it can deliver materials to individual cells. This could aid in the precise delivery of toxic chemotherapy drugs in cancer patients.

The research group has already begun trials in which they inject doses of nanodiamonds into both healthy and cancerous cells.

In a story on the McCormick School’s website, Ho said, “This allows us to deliver a precise dose to one cell and observe its response relative to its neighbors. This will allow us to investigate the ultimate efficacy of novel treatment strategies via a spectrum of internalization mechanisms.”

In a different application, they are using the nanofountain probe to lay down arrays of drug-coated nanodiamonds on glass substrates. This array-production aspect of their work mainly serves to provide a  proof-of-concept for future manufacturing of  patch-like devices for the delivery of nanomaterials. The probe provides a method for controlling dosage and precisely distributing the materials upon the substrate. The patch approach, itself, is advantageous because it theoretically provides a way of delivering precise, low-level amounts a chemotherapy drugs for months at a time. Ho has already worked with a polymer patch covered with a layer of drug-coated nanodiamonds, which moderate the release of the drug.

The use of films containing drug-coated nanodiamonds isn’t particularly novel, but Espinosa and Ho are taking it farther by offering a method to have patterned arrays composed of multiple drugs. Ho says. “This allows high-fidelity spatial tuning of dosing in intelligent devices for comprehensive treatment.” They claim the patterning resolution represents an improvement of three orders of magnitude over previous schemes to deposit nanodiamonds.

“One of the most significant aspects of this work is the Nanofountain Probe’s ability to deliver nanomaterials coated with a broad range of drugs and other biological agents,” Espinosa says. “The injection technique is currently being explored for delivery of a wide variety of bio-agents, including DNA, viruses and other therapeutically relevant materials.”

Ho and Espinosa also think the high-resolution ability of their probe will also be a benefit to the development of nanoelectronics, providing a controlled way to “seed” the growth of diamond thin films. Nanodiamonds have also proven effective in seeding the growth of diamond thin films

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“You know that we are living in a material world” - Madonna

• Atomic layer deposition infusement make spider silk super strong.
  
• Missouri S&T prof working on PV and lithium battery improvements.
  
• Federal incentives helping Oregon’s Solarworld.
  
• Versa Power eyes SOFC manufacturing plant.
  
• RAK Ceramics has over 115 million square metres in annual production capacity.
  
• Report on the Nanotechnology Market with Forecast to 2013.
  
• Jim Good Named President of Kyocera Tycom Corp.

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Researchers at Rensselaer Polytechnic Institute believe that the speed at which heat moves between two materials that touch one another indicates the strength of the bond between them. Moreover, they believe that flow of heat from one material to the other – in their case, between one solid and one liquid – can be altered by painting a thin atomic layer between the materials. That is, when the interface changes, the interaction between the materials changes.

“If you have a nanoparticle that is inside a liquid solution, you can’t just ‘peel away’ the liquid to measure how strongly it is bonded to the surrounding molecules,” says Pawel Keblinski, professor in RPI’s Department of Materials Science and Engineering. Keblinski, who co-led the study, further says, “Instead, we show that you can measure the strength of these bonds simply by measuring the rate of heat flow from the nanoparticle to the surrounding liquid.”

Shekhar Garde, who co-led the study with Keblinski, states, “Interfaces are an exciting new frontier for doing fundamental studies of this type. If you peek into complex biological systems – a cell, for example – they contain a high density of interfaces, between different proteins or between protein and water.” Garde, who is Elaine and Jack S. Parker Professor and head of RPI’s Department of Chemical and Biological Engineering, also says, “Our approach possibly provides another handle to quantify how proteins talk to each other or with the surrounding water.”

Kablinski and Garde used molecular dynamics simulations to measure the heat flow between solid surfaces and water. They simulated many surface chemistries and found that thermal conductance was directly proportional to how strongly the liquid adhered to the solid.

“In the case of a mercury thermometer, thermal expansion correlates directly with temperature,” Keblinski says. “What we have done, in a sense, is create a new thermometer to measure the interfacial bonding properties between liquids and solids.”

“We can use this new technique to characterize systems that are very difficult or impossible to characterize by other means,” Garde adds.

Garde continues, “This fundamental discovery, which helps to better understand how water sticks to or flows past a surface, has implications for many different heat transfer applications and processes, including boiling and condensation. Of particular interest is how this discovery can benefit new systems for cooling and displacing heat from computer chips, a critical issue currently facing the semiconductor industry.”

The authors conclude that the study provides new information of the behavior of water at various solid interfaces.

This study, titled “How wetting and adhesion affect thermal conductance of a range of hydrophobic to hydrophilic aqueous solutions,” was published April 13, 2009, by Physical Review Letters. Co-authors of the study include RPI graduate students Natalia Shenogina and Rahul Godawat.

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Via Gizmag, two Fraunhofer Institutes have teamed up to develop a clever and simple way of treating window glass to make it sensitive to motion and, thus, perfect for security purposes. The combination hardware-software system is able to discriminate between expected motion, i.e., a passing car, and suspicious movement that would warrant an alarm. The base of the system is a special coating applied to the glass:

“The glass is coated with a fluorescent material,” explains IAP group manager Dr. Burkhard Elling. “The coating contains nanoparticles that convert light into fluorescent radiation.”

The “light” in this case would actually be the invisible light of a UV lamp(s). Although other light sources could trigger the same reaction, UV presents a less obvious and intrusive approach. At least one sensor tuned to fluorescent light would also positioned on an edge of the glass. In the normal state, the UV is constant shines on the glass and the sensor continuously reads a steady level of fluorescent radiation.  However, if something passes between the lamp and the window glass, the sensor detects a drop in the fluorescent level and triggers an alert. So what happens if light from another source shines on the window (e.g., someone turns on a lamp or light from a passing car illuminates the glass) or a small animal passes near? This is where the software comes in. First, the sensitivity of the system could be tuned to ignore small objects such as a bird or pet animal. Second, the software can distinguish between UV-generated radiation and that which comes from other sources. If several sensors are installed, things can get even more interesting. The software can then start drawing conclusions about the incidental light, or the size, speed and direction of something approaching the window. Fraunhofer researchers are still working to optimize the coating, but they already know that it could be applied either by a spray (during manufacturing or as an aftermarket add-on) or by rolling on a film. Fraunhofer’s Applied Polymer Research IAP (Potsdam-Golm, Germany) and Computer Architecture and Software Technology FIRST (Berlin) institutes are behind these innovations.

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Everyone else is doing their “tops” list for last year, so who are we to go against the herd?

#5 - Aerogel - Solid smoke!

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#4 - Nanotube Audio Speakers - what stretches, is nearly invisible and can be worn?

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#3 - Chu, scientist and Nobel laureate, tapped for DOE head - Chu’s comments explain why Obama’s choice is being highly praised.

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#2 - Prince Rupert’s Drops - everyone’s favorite glass demonstration.

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#1 - Cracking up over mugs

- Ceramic Mug Drop competition at MS&T’08 (Go figure!?!)

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