Imagine a device small enough to fit in your pocket yet capable of detecting multiple diseases from a breath. The future of health diagnostics is here!
In a world facing health threats—from viruses to chronic diseases and drug-resistant bacteria—the demand for fast, reliable, and easy-to-use home diagnostic tests is higher than ever. Imagine a future where these tests can be performed anywhere, by anyone, with a device like a smartwatch. To make this possible, we need microchips to detect even the smallest traces of viruses or bacteria in the air. Researchers at NYU Tandon have shown that it’s possible to develop microchips that can identify multiple diseases from a single cough or air sample, and these chips can be mass-produced.
Current methods, like drop-casting bioreceptors onto the FET surface, need more precision and scalability for complex diagnostics. Researchers are exploring new ways to modify FET surfaces, enabling each transistor to detect a different biomarker. This would allow for the detection of multiple pathogens at once.
One solution is thermal scanning probe lithography (tSPL), a technology that enables chemical patterning of a polymer-coated chip. This technique allows individual FETs to be functionalized with different bioreceptors, such as antibodies or aptamers, with resolution as small as 20 nanometers—matching the scale of today’s semiconductor transistors. This method allows for modification of each transistor, enabling FET-based sensors that can detect various pathogens on a single chip with high sensitivity.
In tests, FET sensors functionalized with tSPL detected 3 attomolar (aM) concentrations of SARS-CoV-2 spike proteins and as few as 10 live virus particles per milliliter, distinguishing between different viruses like influenza A. This ability to detect tiny amounts of pathogens with precision is a step toward creating portable diagnostic devices for use in hospitals, homes, and other settings.
As semiconductor manufacturing advances, integrating billions of FETs onto microchips, the potential for using these chips in biosensing grows. A method for functionalizing FET surfaces with nanoscale precision could lead to diagnostic tools that detect multiple diseases in real-time, transforming medicine.
Reference:  Alexander James Wright et al, Nanoscale-localized multiplexed biological activation of field effect transistors for biosensing applications, Nanoscale (2024). DOI: 10.1039/D4NR02535K
