Featured Research

from universities, journals, and other organizations

New Devices Harness Carbon Nanomaterials For Drug Delivery Systems, Oxygen Sensors

Date:
August 18, 2009
Source:
University of Pittsburgh
Summary:
Two nanoscale devices recently reported in two separate journals harness the potential of carbon nanomaterials to enhance technologies for drug or imaging agent delivery and energy storage systems, in one case, and, in the other, bolster the sensitivity of oxygen sensors essential in confined settings, from mines to spacecrafts.

Two nanoscale devices recently reported by University of Pittsburgh researchers in two separate journals harness the potential of carbon nanomaterials to enhance technologies for drug or imaging agent delivery and energy storage systems, in one case, and, in the other, bolster the sensitivity of oxygen sensors essential in confined settings, from mines to spacecrafts.

Related Articles


In a report published online by Advanced Materials Aug. 12, a team led by chemistry professors Alexander Star and Stιphane Petoud in Pitt's School of Arts and Sciences describe the creation of nanosized capsules that are universally compatible with a range of substances, particularly related to medicine and energy. When applied to medicine, the tiny vessels can potentially carry a sizable "cargo" of anticancer drugs or medical-imaging agents, and could be steered via antibodies and biological molecules to specific locations within the human body. Energy applications include the storage of lithium and hydrogen in batteries and fuel cells. Pitt graduate chemistry student Brett Allen was the paper's lead author. The project also included chemistry graduate student Chad Shade and Adrienne Yingling, now a graduate of Pitt's PhD chemistry program.

In a separate paper appearing online in Nature Chemistry Aug. 16, another team headed by Star and Petoud revealed the development of a highly sensitive, fluorescent oxygen sensor that can detect minute amounts of the gas. Oxygen detectors are important safety devices in mines, aircraft, submarines, and other confined spaces, the researchers note. The sensor consists of carbon nanotubes coated with a luminescent compound incorporating europium, a reactive metal found in fluorescent bulbs, television/computer screens, and lasers, among other applications.

The researchers gauged oxygen levels by measuring the intensity of its glow when exposed to ultraviolent light and the tubes' change in electrical conductance. The tubes demonstrated sensitivity to oxygen concentrations as low as 5 percent (normal atmospheric concentration is around 20 percent) with the team calculating that it can indicate a level as low as 0.4 percent, and they were unaffected by other atmospheric gases, such as carbon dioxide and nitrogen. The second paper was authored by Shade and Pitt chemistry graduate students Douglas Kauffman and Hyounsoo Uh.

For both technologies, the Pitt teams worked with carbon nanomaterials to create enhanced versions of existing technologies. For instance, the oxygen sensor combines the small scale of carbon nanotubes—they are one-atom thick rolls of graphite 100,000 times smaller than a human hair—with the reactivity of the europium compound coating to produce a platform for low-cost, room-temperature detectors that are notably sensitive to oxygen but less complicated than existing sensors, the researchers write in Nature Chemistry.

Regarding the nanocapsules described in Advanced Materials, existing technologies are typically constructed of polymers that are permeable like a sponge and can result in leakage, Star explained. Additionally, each capsule must be tailored to its particular cargo, he said. The Pitt version employs graphite carbon shells bonded with glutaraldehyde—a common biological adhesive—creating a hollow storage space. More importantly, the graphite shells are chemically inactive and are thus compatible with any cargo substance without costly and time-consuming chemical preparation, Star said.

"For decades, researchers have been searching for an optimal vessel for storing and transporting a variety of cargo to specified locations," Star said. "Our devices have the potential to be universal delivery vehicles for a range of materials. Our next steps will focus on controlling how and when the nanocapsules open by using different stimuli such as pH, light, and chemical agents."

To illustrate the capsules' adaptability, the team loaded them with a luminescent imaging agent developed in Petoud's lab made of zinc sulfide semiconductor nanocrystals incorporating terbium, a metal chemically similar to europium. Once in the body, the substance would emit a unique light that allows easier detection and a better image, Petoud said. But the inorganic nanocrystals have to be prepared before being introduced to a biological environment such as the body and is difficult and time-consuming. The graphite nanocapsules, however, could hold and transport the solution with no preparation.


Story Source:

The above story is based on materials provided by University of Pittsburgh. Note: Materials may be edited for content and length.


Cite This Page:

University of Pittsburgh. "New Devices Harness Carbon Nanomaterials For Drug Delivery Systems, Oxygen Sensors." ScienceDaily. ScienceDaily, 18 August 2009. <www.sciencedaily.com/releases/2009/08/090817190745.htm>.
University of Pittsburgh. (2009, August 18). New Devices Harness Carbon Nanomaterials For Drug Delivery Systems, Oxygen Sensors. ScienceDaily. Retrieved January 25, 2015 from www.sciencedaily.com/releases/2009/08/090817190745.htm
University of Pittsburgh. "New Devices Harness Carbon Nanomaterials For Drug Delivery Systems, Oxygen Sensors." ScienceDaily. www.sciencedaily.com/releases/2009/08/090817190745.htm (accessed January 25, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Sunday, January 25, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

NTSB: Missing Planes' Black Boxes Should Transmit Wirelessly

NTSB: Missing Planes' Black Boxes Should Transmit Wirelessly

Newsy (Jan. 23, 2015) — In light of high-profile plane disappearances in the past year, the NTSB has called for changes to make finding missing aircraft easier. Video provided by Newsy
Powered by NewsLook.com
Iconic Metal Toy Meccano Goes Robotic

Iconic Metal Toy Meccano Goes Robotic

Reuters - Innovations Video Online (Jan. 22, 2015) — Classic children&apos;s toy Meccano has gone digital, releasing a programmable kit robot that can be controlled by voice recognition. The toymakers say Meccanoid G15 KS is easy to use and is compatible with existing Meccano pieces. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
The VueXL From VX1 Immersive Smartphone Headset!

The VueXL From VX1 Immersive Smartphone Headset!

Rumble (Jan. 22, 2015) — The VueXL from VX1 is a product that you install your smartphone in and with the magic of magnification lenses, enlarges your smartphones screen so that it&apos;s like looking at a big screen TV. Check it out! Video provided by Rumble
Powered by NewsLook.com
Analysis: NTSB Wants Better Black Boxes

Analysis: NTSB Wants Better Black Boxes

AP (Jan. 22, 2015) — NTSB investigators recommended Thursday that long-distance passenger planes carry improved technology to allow them to be found more easily in a crash, as well as include enhanced cockpit recording technology. (Jan. 22) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins