Home >
New opportunities from old chemistry in surface science, say Purdue chemists
Some century-old chemistry could have a strong impact on important issues in biosensors and other nanotech devices, according to a Purdue University research group.
(I-Newswire) - A team led by Alexander Wei has shown that amines, a large and important class of organic molecules, when mixed with carbon disulfide, can bond to gold more robustly than thiols, which are commonly used materials for giving new functions to metal surfaces. Gold surfaces are often used as baseplates of sensors and in nanomaterials, and scientists have been searching for stable organic coatings they can attach to gold to form an interface between the organic and inorganic worlds. The group's findings suggest that amines may be the best candidate group of such materials.
"Amines could allow us to expand the range of molecules which can be incorporated into sensors for the biotech field," said Wei, who is an associate professor of chemistry in Purdue's College of Science. "Amines react with carbon disulfide to form dithiocarbamates ( DTCs ) and appear to be better suited for coating surfaces than thiols, which have been the standard thus far. The DTC chemistry itself has been around for over 100 years, but we think it can offer many opportunities for current applications in biosensors and nanotechnology."
Wei performed the study with his Purdue colleagues Yan Zhao, Waleska Pérez-Segarra and Qicun Shi. Their work appeared in this week's ( Vol. 127, No. 20 ) issue of the Journal of the American Chemical Society.
Nanotechnologists and other materials scientists use gold as an interface between electronic components and organic or biomolecular substances. Gold's conductivity and resistance to corrosion makes it an ideal surface for attaching molecules that can detect the presence of proteins in the blood that indicate disease, for example.
"Up to this point, the standard practice has been to modify gold surfaces with thiols, because they are relatively easy to work with and form coatings quickly," Wei said. "Thiols are well known to adsorb, or stick, onto gold surfaces to form highly uniform films with adjustable surface properties. But a drawback to thiols is their intermittent hold on the surface, and the relatively weak chemical bond makes them less attractive for applications that require environmentally durable coatings."
Wei's team found that converting amines into DTCs empower them with an ability to grasp gold surfaces with a strength that thiols do not possess.
"As DTCs, the amines are armed with a 'pincer' made of two sulfur atoms," Wei said. "Thiols are typically bonded to gold by one sulfur atom, like pins stuck in a gold pincushion. DTCs are more like a vice grip, so we hope they will last longer on the gold."
Wei said that although DTCs have been around for a long time, their application to surface chemistry has been overlooked and is long overdue. But Wei cautions that further studies are needed to establish the full scope and limitations of DTCs for various applications.
Wei is associated with Purdue's Birck Nanotechnology Center, which will be one of the largest university facilities in the nation dedicated to nanotechnology research when construction is completed in the summer of 2005. Nearly 100 groups associated with the center are pursuing diverse research topics such as nanometer-sized machines, advanced materials for nanoelectronics and nanoscale biosensors.
This research was funded in part by the National Science Foundation Writer: Chad Boutin, ( 765 ) 494-2081, cboutin@purdue.edu Source: Alexander Wei, alexwei@purdue.edu Purdue News Service: ( 765 ) 494-2096; purduenews@purdue.edu
Related Web site: Previous story on Wei's research
ABSTRACT
Dithiocarbamate Assembly on Gold Yan Zhao, Waleska Pérez-Segarra, Qicun Shi and Alexander Wei
Gold surfaces are functionalized by stable dithiocarbamate ligands when exposed to carbon disulfide and secondary amines. The adsorbed dithiocarbamates are robust under a wide pH range and can resist displacement by other chemisorptive surfactants, providing an attractive method for conjugating sensitive molecules onto metal surfaces.
Contact: Chad Boutin cboutin@purdue.edu 765-494-2081 Purdue University http://www.purdue.edu
If you have questions regarding information in this press release contact the company listed below. I-Newswire.com is a press release service and not the author of this press release. The information that is on or available through this site is for informational purposes only and speaks only as of the particular date or dates of that information. As some companies / PR Agencies submit their press releases once per week/month or quarter, make sure check the official company website for accurate release dates as our site displays the I-Newswire.com distribution date only. We do not guarantee the accuracy or completeness of information on or available through this site, and we are not responsible for inaccuracies or omissions in that information or for actions taken in reliance on that information.
ThePennyStockGuru.com is pleased to offer its stock alerts service to the investing community. Investors who are interested in stocks on the move and in the news can receive FREE Alerts by visiting the following link: http://www.ThePennyStockGuru.com
Players can win thousands of dollars on a daily, weekly and per league basis by playing PSX developed by MySportsBroker Ltd. The PSX tests the players’ knowledge of sports in a contest environment.
Serious rockers buy Guitar Hero 3 bundle because they take the game seriously. As soon as the latest Guitar Hero installment has been released, they want to get their hands on these as soon as possible. Like in the case of the Guitar Hero III game.
The Webkinz Toys are a hit to kids today. They are like the blockbuster movie when it comes to toys. If you go to kids´ bedrooms, chances are you would see these high tech dogs and cats on their shelves.
Atlantic Street Capital Partners secures the management consulting services of Ahern and Associates to develop a long term growth strategy for future transportation acquisitions.
So you´re out there to get disability insurance but you have no idea how much these plans normally cost. You can canvas through the insurance companies and compare which plans provide you with the best rate that go with your lifestyle and budget.
Bank Foreclosure Auction becoming the new style in the United StatesThe first and foremost doubt that many people might get is regarding the profit that could be god with a bank foreclosure auction. In fact it is a real good means to see some pro
You´re renting a home. It could be an apartment or it could be a unit in a condominium. Don´t join those people who think that they need not buy renters insurance because this is a contrary belief.
There is way for you to get the cash you need If you have to consolidate the high interest of your credit card debt or you have to pay the college tuition of your children. You can opt for VA loan refinancing for home equity. This can make great impr
