New Delhi, Aug 25 (IANS) – Researchers at the Indian Institute of Technology Madras (IIT Madras) have created a low-cost, microfluidic “lab-on-chip” device capable of quickly determining whether bacteria are resistant or sensitive to antibiotics.
Antimicrobial Susceptibility Testing (AST) is critical for identifying effective antibiotics for an infection. It helps clinicians select appropriate treatment while reducing the misuse of antibiotics—a key driver of antimicrobial resistance (AMR).
Unlike conventional methods that depend on expensive metals, complex fabrication, or highly skilled operators, the new device — called ‘ε-µD’ — uses screen-printed carbon electrodes integrated into a simple microfluidic chip. This design makes it highly affordable and ideal for deployment in smaller clinics and rural healthcare facilities. Importantly, it delivers results in just three hours.
“This device can make a significant difference for ICU patients with severe bacterial infections. It enables faster, more targeted treatment, which could be lifesaving,” said Prof. S. Pushpavanam from IIT Madras’ Department of Chemical Engineering.
AMR has emerged as one of the biggest global health threats, with the WHO listing it among the top 10 global health risks. In 2019, bacterial AMR was linked to nearly 4.95 million deaths worldwide.
Traditional AST methods involve culturing bacteria and observing their antibiotic response — a labor-intensive process that can take 48–72 hours. This delay often forces doctors to prescribe broad-spectrum antibiotics, inadvertently worsening resistance.
The IIT Madras device, however, uses electrochemical signals to measure bacterial growth and antibiotic susceptibility in three hours.
In tests published in Nature Scientific Reports, researchers evaluated the device using two bacterial strains:
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Gram-negative E. coli
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Gram-positive B. subtilis
They tested two antibiotics with different mechanisms: ampicillin (kills bacteria) and tetracycline (inhibits growth). The device successfully identified susceptibility profiles within the three-hour window.
Additionally, trials on urine samples spiked with E. coli confirmed its ability to detect tetracycline resistance, underscoring its potential for clinical diagnostic use.
With its low cost, speed, and ease of use, this innovation could revolutionize how infections are diagnosed and treated, especially in resource-limited settings.
