Featured Research

from universities, journals, and other organizations

Quicker, Cheaper SARS Virus Detector -- One Easily Customizable For Other Targets

Date:
June 1, 2009
Source:
University of Southern California
Summary:
Researchers say they've made a big improvement in a new breed of electronic detectors for viruses and other biological materials -- one that may be a valuable addition to the battle against epidemics.

Antibody mimic protein is tailored to attach to nanowire base at one end, leaving biologically active area open for detection.
Credit: University of Southern California

Members of a USC-led research team say they've made a big improvement in a new breed of electronic detectors for viruses and other biological materials — one that may be a valuable addition to the battle against epidemics.

It consists of a piece of synthetic antibody attached to a nanowire that's attached to an electrical base, immersed in liquid.

If the protein the antibody binds to is present in the liquid, it will bind to these antibodies, immediately creating a sharply measurable jump in current through the nanowire.

The basic principle of nanotube and nanowire biosensors for protein detection was first demonstrated in 2001, but the new design by a team headed by Zhongwu Chou and Mark Thompson of the University of Southern California uses two new elements.

First, it takes advantage of bioengineered synthetic antibodies, much, much smaller versions of the natural substances that are designed to bind with a specific protein and only that protein.

Second, it uses indium oxide (In2O3) nanowires instead of silicon and other materials previously tried. Metal oxides, according to a new study published in ACS Nano, do not, unlike silicon, develop "an insulating native oxide layer that can reduce sensitivity."

The result, according to the paper, is a device that can detect its target molecules with a sensitivity as great as the best alternative modes, do so more rapidly and without use of chemical reagents.

It is also potentially considerably cheaper than alternatives.

"We believe," the authors write, "that nanowire bisensor devices functionalized with engineered proteins … can have important applications ranging from disease diagnosis to homeland security."

Additionally, the system can be useful in basis research, in helping to establish certain important parameters for two-part biological systems like the antibody/target protein pair.

The protein the prototype system detects is the SARS (severe acute respiratory syndrome) virus n-protein, which infected more than 8,000 people in 2002-2003, killing nearly 10 percent of them.

Commercial systems using enzyme-linked immunosorbent assay (ELISA) now exist to test for SARS, but the new system has advantages in time, cost and portability.

The first step was the creation, by Richard Roberts and Mark Thompson, chemists, and their team of the synthetic antibody, including both the active area, design to interact with the protein and, at the other end, a chemical "hook" that would bind it to nanowire at this point and only this point. "This … strategy allows every bound [detector molecule] to retain full activity, a clear advantage over antibodies, which [in earlier biosensor designs] are often bound to nanowire surface via amine containing residues randomly distributed over the antibody surface."

The Zhou lab, which has specialized in nanowire and nanotube technology for years, performed the complex set of procedures to synthesize the wires, attaching

In tests, the group performed if anything better than predictions, showing a standard and low level of activity when no SARS protein was present, leaping quickly to a higher level when the protein was introduced, in response patterns that varied consistently according to concentration of the SARS protein. Devices complete except for the detector molecule showed no response at all.

The response was complete in less than ten minutes, compared to hours needed for results from ELISA tests - which are basically present/not present tests with relatively little quantitative elements.

Next steps are to enable detection in more complex environment, such as Serum and whole blood, by integrating the nanobiosensor with micro systems such as microfluidics chips and micro filters.

The USC team believes their new system has potential to be cheaper and more portable than either.

In addition to Zhou (from the Viterbi School's Ming Hsieh Department of Electrical Engineering) and Thompson (of the USC College Department of Chemistry), the team included Fumiaki Ishikawa, Hsaio-Kang Chang, Po-Ching Chen from Electrical Engineering; Marco Curreli, Rui Zhang, Richard W. Roberts and C. Anders Olson from Chemistry, Richard J. Cote of the Keck School of Medicine at USC Department of Pathology, and Hsiang-I Liao and Ren Sun of the UCLA Department of Medical Pharmacology.

The Whittier Foundation and the National Institutes of Health funded the research.


Story Source:

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


Journal Reference:

  1. Fumiaki N. Ishikawa, Hsiao-Kang Chang, Marco Curreli, Hsiang-I Liao, C. Anders Olson, Po-Chiang Chen, Rui Zhang, Richard W. Roberts, Ren Sun, Richard J. Cote, Mark E. Thompson and Chongwu Zhou. Label-Free, Electrical Detection of the SARS Virus N-Protein with Nanowire Biosensors Utilizing Antibody Mimics as Capture Probes. ACS Nano, 2009; 3 (5): 1219 DOI: 10.1021/nn900086c

Cite This Page:

University of Southern California. "Quicker, Cheaper SARS Virus Detector -- One Easily Customizable For Other Targets." ScienceDaily. ScienceDaily, 1 June 2009. <www.sciencedaily.com/releases/2009/05/090529093152.htm>.
University of Southern California. (2009, June 1). Quicker, Cheaper SARS Virus Detector -- One Easily Customizable For Other Targets. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2009/05/090529093152.htm
University of Southern California. "Quicker, Cheaper SARS Virus Detector -- One Easily Customizable For Other Targets." ScienceDaily. www.sciencedaily.com/releases/2009/05/090529093152.htm (accessed July 23, 2014).

Share This




More Matter & Energy News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com
Boeing Ups Outlook on 52% Profit Jump

Boeing Ups Outlook on 52% Profit Jump

Reuters - Business Video Online (July 23, 2014) Commercial aircraft deliveries rose seven percent at Boeing, prompting the aerospace company to boost full-year profit guidance- though quarterly revenues missed analyst estimates. Bobbi Rebell reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Car Market on the Rebound?

Europe's Car Market on the Rebound?

Reuters - Business Video Online (July 23, 2014) Daimler kicks off a round of second-quarter earnings results from Europe's top carmakers with a healthy set of numbers - prompting hopes that stronger sales in Europe will counter weakness in emerging markets. Hayley Platt reports. Video provided by Reuters
Powered by NewsLook.com
9/11 Commission Members Warn of Terror "fatigue" Among American Public

9/11 Commission Members Warn of Terror "fatigue" Among American Public

Reuters - US Online Video (July 22, 2014) Ten years after releasing its initial report, members of the 9/11 Commission warn of the "waning sense of urgency" in combating terrorists attacks. Mana Rabiee reports. Video provided by Reuters
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:
from the past week

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