 "BITS Pilani develops flexible gold electrodes for cardiac detection")
Researchers at BITS Pilani Hyderabad’s MMNE Lab have developed thin, flexible gold electrodes capable of detecting cardiac troponin I (cTnI) — a biomarker for heart attacks — and uric acid in human saliva.
The development, published in the Chemical Engineering Journal, offers a portable alternative to conventional laboratory-based cardiac tests and could be used in settings with limited infrastructure.
The device is currently under evaluation in collaboration with startups, hospitals, and government agencies. Discussions are ongoing with regulatory bodies such as the Indian Council of Medical Research (ICMR) and the Central Drugs Standard Control Organisation (CDSCO) for clinical trials and certification. The team is also exploring applications beyond cardiac biomarkers, including kidney and liver diagnostics, and plans to seek regulatory approval in international markets.
Low-cost fabrication and flexibility across materials
The electrodes were fabricated using physical vapour deposition (PVD) on flexible substrates such as photo paper and polyimide, as well as conventional silicon and glass. The process does not require lithography or multiple solvents, reducing fabrication time and complexity.
The electrodes are 50 nanometres thick, exhibit crystalline morphology, and can be produced in about 2.5 hours.
High sensitivity, stability and multi-biomarker potential
The sensors were tested for sensitivity and selectivity. Cardiac troponin I could be detected at concentrations as low as 0.85 ng/mL, while uric acid detection from saliva samples was possible at 0.30 mM. The electrodes showed minimal interference from other biomolecules, including ascorbic acid, dopamine, and common ions.
Stability tests indicated functionality for at least one month under storage conditions. Recovery rates for uric acid from human saliva samples ranged between 95 and 98 per cent.
The electrodes are compatible with commercial portable potentiostats, enabling electrochemical measurements outside conventional laboratories. While reusable, single-use applications are recommended for medical testing.
Designed for scalability and portable health monitoring
“The electrodes are designed to be flexible and compatible with multiple substrates, which allows testing outside standard laboratory setups,” said Sanket Goel, Birla Chair Professor and Head, Centre for Research Excellence in Semiconductor Technologies. “We focused on creating a fabrication method that is straightforward and can be scaled for low-cost production.”
Although the electrodes use gold, the thickness is only 50 nanometres. On paper-based substrates, the reported cost per electrode is around ₹10–20. Mass production using printing techniques could bring the cost down to below ₹1 per electrode.
The PVD-based fabrication method allows adaptation for other biomarkers through surface modification and integration with flexible electronics, supporting industrial-scale manufacturing of low-cost biosensors.
Next steps: scaling up, trials, and connected diagnostics
The research team plans to scale production using printed electronics methods and conduct larger clinical trials. Data from the device can be transmitted to cloud platforms for remote analysis.
Potential applications include clinical settings, portable health monitoring devices, and remote diagnostic centres, enabling decentralised testing without the need for specialised personnel or laboratory infrastructure.
The project involves Sanket Goel and a team of postdoctoral and doctoral researchers, including Aniket, Parvati, and Sonal. The broader research focuses on three areas:
ECG-based detection using single-lead devices with machine learning
Biomarker detection through electrochemical sensors
Cardiac cell-on-chip studies for drug response and toxicity testing