guwahati researchers at indian institute of technology guwahati have developed a lowcost handheld device to detect bacteria well almost instantaneously without the time consuming cell culture and microbiological assaysa spokesman of the premier institute statedthis research by iit guwahati will enable rapid detection of bacteria which is important not only in healthcare but also in antibioterrorism measures and environmental monitoring applicationsthe research team is led by prof parameswar k iyer of department of chemistry and prof siddhartha s ghosh of department of biosciences and bioengineering of the institute the other members of the dr anamika dey dr ashish singh and dr deepanjalee dutta all three former phd scholars from center for nanotechnology iitgtheir work has been patented as well as published in the july 2019 issue of the reputed peerreviewed journal of materials chemistry a of the royal society of chemistryat 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 analysisexplaining the need to develop faster and easier methods to detect bacteria prof iyer said current diagnostic processes are frustratingly timeconsuming especially when time is of the essence in administering treatment what would be useful are handheld rapid detection kits like those used for blood sugar monitoring and pregnancy detectionhighlighting the functionality of the device prof 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 detectionthe important breakthrough by the team was in developing and using an organic field effect transistor ofet to detect this surface charge the ofet is an electronic device that works on the principle that charges in the vicinity of the channels of certain semiconductors can induce a current in them thus the charges on the surface of the bacterium induces a current in the ofet which is registered and readthe ofet devices developed by the team consists of a unique and hybrid trilayer dielectric system built on simple glass and flexible pet a kind of plastic substrates and can operate at ultralow operating voltages the team has shown that this ofet sensor can not only detect bacteria but also differentiate between gram positive and gram negative bacterianot only have we shown the sensing capabilities of this portable ofet device but we have also shown the mechanism by which sensing occurs and elucidated the role of bacterial wall in distinguishing various bacterial types added prof iyer on the significance of this latest interdisciplinary research workthe ofetbased readytouse diagnostic tool will facilitate rapid detection and diagnosis at the point of care the current device is particularly useful for the detection of bacteria primarily for waterborne diseases these sensors will also be useful in instantaneous detection of timecritical illnesses such as meningitis