09 Mar 2004
Blowing into a portable breath analyzer gives a rapid and convenient way to screen for TB.
A UK start-up has invented a portable optical biosensor that screens for tuberculosis (TB) by analyzing a person's breath. According to its developers, Cambridge-based Rapid Biosensor Systems (RBS), its prototype breath analyzer is not only portable and easy to use but also gives almost instantaneous results.
Clinical trials are about to start in the UK and India and RBS is now searching for health-care firms that are interested in purchasing a license in the technology. TB currently kills around 2 million people each year and is a growing problem not only in developing countries but also in first world countries including the UK.
"Our test is very fast and gives results within 10 to 15 minutes, you simply cough into a tube," said Dennis Camilleri, the chief executive officer of RBS. "Potentially it could do away with the need for an injection skin test which has a much longer turnaround time."
The testing process is very simple. If TB bacteria are present in the breath sample then they bind to a special fluorescent bio-coating that has been applied to an optical prism inside a collection tube.
The tube is then placed inside an optical reader which couples light from a laser diode into the prism in order to excite fluorescence from the coating. Analysis of the fluorescence signal indicates if TB is present.
The compact size of the system means that it is completely portable. The collection tube resembles an asthma inhaler while the reader fits comfortably in the hand.
Camilleri says that because the system does not require samples to be sent off to a lab for analysis it could potentially be used at airports and seaports to screen people as they enter a country. This enables the screening to be done "while you wait" and so people with positive TB screening results can be isolated immediately.
As for future developments, by changing the pathogen binding-properties of the coating the sensor could be designed to work for other non-airborne diseases.
"Nothing on the market comes close to our system in terms of size, durability and results turnaround," said Camilleri. "As well as instant testing for TB, the kit also offers detection for E Coli for which we are now completing extensive laboratory testing."