New sensor sniffs for pathogens

Students at Illinois Institute of Technology have developed a sensing technology that will allow doctors to detect and identify pathogens in the blood much faster than conventional lab tests can.

Students at Illinois Institute of Technology (IIT) have developed a sensing technology that will allow doctors to detect and identify pathogens in the blood much faster than conventional lab tests can.

The sensing device, known as an electronic nose, is an array of small sensors that can detect gases given off by microscopic organisms including bacteria that can infect the blood such as e. coli and staphylococcus bacteria. The sensors are linked to a computer that can analyse the gas signature and compare it to signatures from known pathogens.

Currently, labs use methods that can take up to 48 hours to identify pathogens in the blood. IIT’s electronic nose can reportedly cut the time to 24 hours.

Electronic noses are arrays of sensors that are sensitive to microscopic particles, which are similar to receptors in the nose. ‘There are millions of neurons that bind molecules in the nose that the brain recognises as specific odours,’ said senior student Christopher Morong.

‘The e-nose is the same way, except it only has eight sensors, but it still has the potential to identify hundreds of specific scent signatures.’ Electronic noses that can identify the presence of the tuberculosis bacteria are also in development at IIT.

The blood sniffing e-nose was developed by students in IIT’s Interprofessional Program (IPRO), which brings together students from different disciplines at different experience levels to solve a problems posed by companies or IIT faculty.

The e-nose was developed in response to lab technicians at Provident Hospital in Chicago who noticed that when testing blood for pathogens, there would often be certain odours that were strongly linked to the type of pathogen they would find.

If they could definitively link the odours to a type of pathogen, they could cut testing time down. To test blood for pathogens, lab technicians have to culture the blood for 24 hours, allowing any bacteria in it to grow to detectable levels. The culture is then tested for specific pathogens.

The whole process takes about 48 hours. ‘Ultimately, we’d like to be able to take blood from a patient, and use the e-nose to sniff out the pathogens right away,’ said Morong. ‘But without growing the pathogen up, it’s hard to detect any gases.’