Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Researchers write protein nanoarrays using a fountain pen and electric fields

Abstract:
Nanotechnology offers unique opportunities to advance the life sciences by facilitating the delivery, manipulation and observation of biological materials with unprecedented resolution. The ability to pattern nanoscale arrays of biological material assists studies of genomics, proteomics and cell adhesion, and may be applied to achieve increased sensitivity in drug screening and disease detection, even when sample volumes are severely limited.

Researchers write protein nanoarrays using a fountain pen and electric fields

EVANSTON, IL | Posted on October 13th, 2008

Unfortunately, most tools capable of patterning with such tiny resolution were developed for the silicon microelectronics industry and cannot be used for soft and relatively sensitive biomaterials such as DNA and proteins.

Now a team of researchers at Northwestern University has demonstrated the ability to rapidly write nanoscale protein arrays using a tool they call the nanofountain probe (NFP).

"The NFP works much like a fountain pen, only on a much smaller scale, and in this case, the ink is the protein solution," said Horacio Espinosa, head of the research team and professor of mechanical engineering in the McCormick School of Engineering and Applied Science at Northwestern.

The results, which will be published online the week of Oct. 13 in the Proceedings of the National Academy of Sciences (PNAS), include demonstrations of sub-100-nanometer protein dots and sub-200-nanometer line arrays written using the NFP at rates as high as 80 microns/second.

Each nanofountain probe chip has a set of ink reservoirs that hold the solution to be patterned. Like a fountain pen, the ink is transported to sharp writing probes through a series of microchannels and deposited on the substrate in liquid form.

"This is important for a number of reasons," said Owen Loh, a graduate student at Northwestern who co-authored the paper with fellow student Andrea Ho. "By maintaining the sensitive proteins in a liquid buffer, their biological function is less likely to be affected. This also means we can write for extended periods over large areas without replenishing the ink."

Earlier demonstrations of the NFP by the Northwestern team included directly writing organic and inorganic materials on a number of different substrates. These included suspensions of gold nanoparticles, thiols and DNA patterned on metallic- and silicon-based substrates.

In the case of protein deposition, the team found that by applying an electrical field between the nanofountain probe and substrate, they could control the transport of protein to the substrate. Without the use of electric fields, protein deposition was relatively slow and sporadic. However, with proper electrical bias, protein dot and line arrays could be deposited at extremely high rates.

"The use of electric fields allows an additional degree of control," Espinosa said. "We were able to create dot and line arrays with a combination of speed and resolution not possible using other techniques."

Positively charged proteins can be maintained inside the fountain probe by applying a negative potential to the NFP reservoirs with respect to a substrate. Reversing the applied potential then allows protein molecules to be deposited at a desired site.

To maximize the patterning resolution and efficiency, the team relied on computational models of the deposition process. "By modeling the ink flow within the probe tip, we were able to get a sense of what conditions would yield optimal patterns," says Jee Rim, a postdoctoral researcher at Northwestern.

Espinosa collaborated closely with Neelesh Patankar, associate professor of mechanical engineering at Northwestern, and Punit Kohli, assistant professor of chemistry and biochemistry at Southern Illinois University, Carbondale.

"We are very excited by these results," said Espinosa. "This technique is very broadly applicable, and we are pursuing it on a number of fronts." These include single-cell biological studies and direct-write fabrication of large-scale arrays of nanoelectrical and nanoelectromechanical devices.

"The fact that we can batch fabricate large arrays of these fountain probes means we can directly write large numbers of features in parallel," added Espinosa. "The demonstration of rapid protein deposition rates further supports our efforts in producing a large-scale nanomanufacturing tool."

The paper in the Proceedings of the National Academy of Sciences was authored by Loh, Ho, Rim, Patankar, Kohli and Espinosa.

####

For more information, please click here

Contacts:
Megan Fellman

847-491-3115

Copyright © Northwestern University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

The power of perovskite: OIST researchers improve perovskite-based technology in the entire energy cycle, from solar cells harnessing power to LED diodes to light the screens of future electronic devices and other lighting applications August 18th, 2017

Gold nanostars and immunotherapy vaccinate mice against cancer: New treatment cures, vaccinates mouse in small proof-of-concept study August 18th, 2017

Researchers printed graphene-like materials with inkjet August 17th, 2017

Candy cane supercapacitor could enable fast charging of mobile phones August 17th, 2017

Nanomedicine

Gold nanostars and immunotherapy vaccinate mice against cancer: New treatment cures, vaccinates mouse in small proof-of-concept study August 18th, 2017

Freeze-dried foam soaks up carbon dioxide: Rice University scientists lead effort to make novel 3-D material August 16th, 2017

Gold shines through properties of nano biosensors: Researchers discover that fluorescence in ligand-protected gold nanoclusters is an intrinsic property of the gold particles themselves August 16th, 2017

Two Scientists Receive Grants to Develop New Materials: Chad Mirkin and Monica Olvera de la Cruz recognized by Sherman Fairchild Foundation August 16th, 2017

Discoveries

The power of perovskite: OIST researchers improve perovskite-based technology in the entire energy cycle, from solar cells harnessing power to LED diodes to light the screens of future electronic devices and other lighting applications August 18th, 2017

Gold nanostars and immunotherapy vaccinate mice against cancer: New treatment cures, vaccinates mouse in small proof-of-concept study August 18th, 2017

Researchers printed graphene-like materials with inkjet August 17th, 2017

Candy cane supercapacitor could enable fast charging of mobile phones August 17th, 2017

Announcements

The power of perovskite: OIST researchers improve perovskite-based technology in the entire energy cycle, from solar cells harnessing power to LED diodes to light the screens of future electronic devices and other lighting applications August 18th, 2017

Gold nanostars and immunotherapy vaccinate mice against cancer: New treatment cures, vaccinates mouse in small proof-of-concept study August 18th, 2017

Researchers printed graphene-like materials with inkjet August 17th, 2017

Candy cane supercapacitor could enable fast charging of mobile phones August 17th, 2017

Nanobiotechnology

Gold nanostars and immunotherapy vaccinate mice against cancer: New treatment cures, vaccinates mouse in small proof-of-concept study August 18th, 2017

Freeze-dried foam soaks up carbon dioxide: Rice University scientists lead effort to make novel 3-D material August 16th, 2017

Gold shines through properties of nano biosensors: Researchers discover that fluorescence in ligand-protected gold nanoclusters is an intrinsic property of the gold particles themselves August 16th, 2017

Two Scientists Receive Grants to Develop New Materials: Chad Mirkin and Monica Olvera de la Cruz recognized by Sherman Fairchild Foundation August 16th, 2017

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project