Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New biosensor could save lives by giving faster medical analysis

03.07.2002


The biosensor
© EPSRC


Every day accident and emergency units have to treat patients who have taken some sort of drug overdose. To give treatment doctors need to know what the patient has taken. The circumstances can make often this difficult to ascertain quickly.

Researchers are developing a new kind of biosensor, which can determine in minutes if a patient’s blood contains a particular compound, for example paracetamol. Currently this type of examination needs to be carried out in a laboratory, which is expensive and time consuming.

The research is being carried out by Dr Sub Reddy’s team at the University of Surrey with funding from the Swindon based Engineering and Physical Sciences Research Council.



The sensor system can return a response in less than 10 minutes compared to the 2 – 3 hours required by a routine laboratory, depending on their workload. “Our sensor is portable and will be easy to use even by unskilled staff,” says Dr. Reddy. “Ideally, the overdose sensor may be located in the ambulance so that a result is available when the patient arrives at hospital.” The paracetamol sensor is the pilot to the development of an array of overdose sensors, which will test for alcohol and anti-depressants as well.

The capabilities of the biosensor extend far beyond helping patients who have taken a drug overdose. “We have successfully used the system to detect glucose,” says Dr Reddy. The team is also investigating the detection of creatinine, a product in the body, which is an indicator of kidney dysfunction.

The heart of the biosensor consists of a disc-shaped quartz crystal, around a centimetre in diameter and 0.2 mm thick. “When an alternating electric field is applied the crystal vibrates from side to side, like a nano-scale earthquake,” says Dr Reddy. “It shakes ten million times a second with an amplitude of a fraction of a nanometre.” The crystal can continue to oscillate even when immersed in a liquid. Anything which then sticks to the crystal surface or which affects the viscosity or elasticity of any attached film at the surface will affect the frequency at which the crystal vibrates.

The concept of the sensor is to have a small reaction chamber above the surface of the crystal. When a sample – blood, say – is placed in the chamber a series of carefully designed chemical reactions can be made to occur which result in the molecule of interest – for example cholesterol – contributing to the formation of a solid product. The product then attaches to the surface of the crystal, affecting the frequency of its oscillation.

Because the chemical reaction can be made to be highly specific to the molecule of interest so that only one solid product is formed, other substances in the sample will not interfere with the process or provide spurious readings.

Dr. Reddy explained how the biosensor has been used to detect glucose. “Here you add the sample to the reaction mixture. An enzyme oxidises the glucose to form hydrogen peroxide. This in turn is acted upon by a second enzyme and reacts with other ingredients in the mixture to form a water repelling molecule, which comes out of solution and can be made to attach to the quartz. This causes a change in the oscillation frequency which can be correlated with the quantity of product, which can in turn be related to the amount of glucose originally present in the sample.”

Dr Reddy believes that his team has demonstrated the feasibility of the concept of using a quartz crystal sensor in this way. “We have shown that the system has excellent sensitivity. We are getting extremely large signals.”

The researchers are now looking into ways of refining the system, by using membranes above the surface, which are selective for specific types of molecule, for example. This would ‘filter out’ any potentially contaminating species to provide a much cleaner and unambiguous reading. “We are building up a portfolio of detection strategies for compounds of interest and we are now reaching the stage where we are looking for industrial collaborators. We are also applying this viscoelastic sensor to lab-on-a-chip type technologies, as well as integrating it with synthetic polymer films capable of molecular recognition,” says Dr Reddy.

Jane Reck | alfa

More articles from Health and Medicine:

nachricht TSRI researchers develop new method to 'fingerprint' HIV
29.03.2017 | Scripps Research Institute

nachricht Periodic ventilation keeps more pollen out than tilted-open windows
29.03.2017 | Technische Universität München

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>