Featured Research

from universities, journals, and other organizations

Medical sensors improve with holey gold nanostructures

Date:
September 26, 2013
Source:
The Agency for Science, Technology and Research (A*STAR)
Summary:
A new method that fabricates gold nanostructures quickly and efficiently could lead to highly sensitive, portable medical sensors.

Localized surface plasmon resonance (bright areas) around a gold nanohole enhances the fluorescence of a biomarker dye (Y-shaped molecule) when a specific molecule of interest (purple circle) is present.
Credit: A*STAR Institute of High Performance Computing

A new method that fabricates gold nanostructures quickly and efficiently could lead to highly sensitive, portable medical sensorsRecent advances in nanotechnology are providing new possibilities for medical imaging and sensing. Gold nanostructures, for example, can enhance the fluorescence of marker dyes that are commonly used to detect biomolecules and diagnose specific diseases.

Now, Ping Bai at the A*STAR Institute of High Performance Computing, Singapore, and co-workers have developed a fast and inexpensive way to fabricate arrays of gold nanoholes. The researchers have shown that sensor chips built using these nanostructures can accurately detect cancer-related molecules in blood and are small enough to be used in portable medical devices.

Nanohole arrays are designed so that incident light of certain wavelengths will induce large-scale oscillations of the gold electrons, known as localized surface plasmon resonance (SPR). The localized SPR focuses the absorbed light energy to enhance fluorescence (see image).

"Commercial SPR systems are already used in hospital laboratories, but they are bulky and expensive," says Bai. "We would like to develop small, handheld devices for on-the-spot clinical use. This requires localized SPR, for which we need nanohole arrays."

Previously, nanohole arrays have been created using electron-beam lithography (EBL), which is expensive and time consuming. Bai and co-workers used EBL to create a nickel mold and then used the mold to print nanohole patterns onto a photoresist material. The researchers made the nanostructures by evaporating gold onto the patterned structure before peeling off the photoresist material. Because the nickel mold can be reused many times, this method -- called nano-imprinting -- can produce large numbers of gold nanohole arrays.

"We fabricated arrays of 140 nanometer-square nanoholes with very few defects," says Bai. As a first demonstration, the researchers showed that a sensor chip made with their nanohole arrays could detect prostate cancer antigens in blood, and was ten times more sensitive than an identical device that used a gold film without nanoholes. Optimizing the chip design would further improve the sensitivity, Bai notes.

The team believes that these chips could be incorporated into cheap and portable point-of-care devices for rapid diagnosis of diseases such as dengue fever. "The microfluidic cartridge built using our nanohole arrays is about the size of a credit card," says Bai. "In the future, we hope to build detectors that use very simple light sources, such as LEDs, and simple detectors similar to smartphone cameras. These devices will have widespread applications across medical science and could even be used to detect contaminants in food, water or the air."


Story Source:

The above story is based on materials provided by The Agency for Science, Technology and Research (A*STAR). Note: Materials may be edited for content and length.


Journal Reference:

  1. Ten It Wong, Shan Han, Lin Wu, Yi Wang, Jie Deng, Christina Yuan Ling Tan, Ping Bai, Yee Chong Loke, Xin Da Yang, Man Siu Tse, Sum Huan Ng, Xiaodong Zhou. High throughput and high yield nanofabrication of precisely designed gold nanohole arrays for fluorescence enhanced detection of biomarkers. Lab on a Chip, 2013; 13 (12): 2405 DOI: 10.1039/C3LC41396A

Cite This Page:

The Agency for Science, Technology and Research (A*STAR). "Medical sensors improve with holey gold nanostructures." ScienceDaily. ScienceDaily, 26 September 2013. <www.sciencedaily.com/releases/2013/09/130926102101.htm>.
The Agency for Science, Technology and Research (A*STAR). (2013, September 26). Medical sensors improve with holey gold nanostructures. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2013/09/130926102101.htm
The Agency for Science, Technology and Research (A*STAR). "Medical sensors improve with holey gold nanostructures." ScienceDaily. www.sciencedaily.com/releases/2013/09/130926102101.htm (accessed April 24, 2014).

Share This



More Matter & Energy News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

UN Joint Mission Starts Removing Landmines in Cyprus

UN Joint Mission Starts Removing Landmines in Cyprus

AFP (Apr. 23, 2014) The UN mission in Cyprus (UNFICYP) led a mine clearance demonstration on Wednesday in the UN-controlled buffer zone where demining operations are being conducted near the Cypriot village of Mammari. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com
Air Force: $4.2B Saved from Grounding A-10s

Air Force: $4.2B Saved from Grounding A-10s

AP (Apr. 23, 2014) Speaking about the future of the United States Air Force, Chief of Staff Gen. Mark Welsh says the choice to divest the A-10 fleet was logical and least impactful. (April 23) Video provided by AP
Powered by NewsLook.com
Jets Fuel Jump in Boeing's Revenue

Jets Fuel Jump in Boeing's Revenue

Reuters - Business Video Online (Apr. 23, 2014) A sharp rise in revenue for commercial jets offset a decline in Boeing's defense business. And a big increase in deliveries lifted profitability. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Is North Korea Planning Nuclear Test #4?

Is North Korea Planning Nuclear Test #4?

Newsy (Apr. 22, 2014) South Korean officials say North Korea is preparing to conduct another nuclear test, but is Pyongyang just bluffing this time? Video provided by Newsy
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