Indian Institute of Technology, Guwahati researchers have developed a low-cost, hand-held device to detect bacteria. This research by IIT Guwahati will enable rapid detection of bacteria, which is important not only in healthcare, but also in anti-bioterrorism measures and environmental monitoring applications.
Bacterial infection is a common cause of morbidity and mortality worldwide and despite development of a range of antibiotics, the challenge continues to lie in detecting and diagnosing bacterial infection early on, as present detection techniques tend to be time-consuming.
The research team led by Professor Parameswar K Iyer, Department of Chemistry, and Professor Siddhartha S Ghosh, Department of Biosciences and Bioengineering, IIT Guwahati, has developed this low-cost, bio-compatible sensor that can detect bacteria almost instantaneously without the need for cell culture and microbiological assays.
The Organic Field Effect Transistor (OFET)-based bacterial diagnostic device has been shown to have the ability to detect 103 cfu mL−1 of bacteria and distinguish between Gram positive and Gram negative types.
Their work has been patented as well as published in the July 2019 issue of the reputed peer-reviewed Journal of Materials Chemistry A of the Royal Society of Chemistry.
At present, the detection of bacteria in body fluids is done in laboratories. The cells that are derived from the patient are initially cultured or grown so that enough of the bacterial cells are available for microbiological analysis.
Explaining the need to develop faster and easier methods to detect bacteria, Professor Iyer said, “Current diagnostic processes are frustratingly time-consuming, especially when time is of the essence in administering treatment. While newly developed techniques such as real time qPCR can detect bacteria faster than conventional assay-based methods, they are restricted by the need for expensive apparatuses and trained personnel. What would be useful are hand-held rapid detection kits like those used for blood sugar monitoring and pregnancy detection.”
The IIT Guwahati team consisting of Anamika Dey, Ashish Singh, Deepanjalee Dutta (all three former PhD scholars from Center for Nanotechnology, IITG), Professor Siddhartha Sankar Ghosh and Professor Parameswar Krishnan Iyer, brings portable bacterial detection kits closer to reality. The sensor detects the charges on the cell walls of bacteria.
Highlighting the functionality of the device, Professor Ghosh said, “It is known that Gram positive bacteria such as S pneumoniae, have different cell wall compositions than Gram negative bacteria such as the common E coli. Such asymmetric cell wall organizations could alter flow of electrons at the channel of OFETs during their detection”.
