Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Medical sensors improve with holey gold nanostructures

26.09.2013
A new method that fabricates gold nanostructures quickly and efficiently could lead to highly sensitive, portable medical sensors

Recent 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.


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.
Copyright : © 2013 A*STAR Institute of High Performance Computing

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.”

The A*STAR-affiliated researchers contributing to this research are from the Institute of High Performance Computing, Institute of Materials Research and Engineering and Singapore Institute of Manufacturing Technology

Associated links
Wong, T. I., Han, S., Wu, L., Wang, Y., Deng, J. et al. High throughput and high yield nanofabrication of precisely designed gold nanohole arrays for fluorescence enhanced detection of biomarkers. Lab on a Chip 13, 2405–2413 (2013).

http://www.sciencedirect.com/science/article/pii/S0261306913005074

A*STAR Research | Research asia research news
Further information:
http://www.a-star.edu.sg

More articles from Medical Engineering:

nachricht Novel breast tomosynthesis technique reduces screening recall rate
21.02.2017 | Radiological Society of North America

nachricht Biocompatible 3-D tracking system has potential to improve robot-assisted surgery
17.02.2017 | Children's National Health System

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>