The recent pandemic has underscored the critical need for early sensor diagnosis for effective treatment, emphasizing the importance of accessible and efficient healthcare services. Novel biosensors, especially optical biosensors based on localized surface plasmon resonance (LSPR), are emerging as promising diagnostic tools due to their real-time, cost-effective analytical capabilities.

Despite advances, there is a gap in developing LSPR sensors that combine high sensitivity with low fabrication costs for broad applications. This research addresses this gap by fabricating a library of hundreds of nanostructures with varying sizes and periodicities on a single platform, allowing for a comprehensive experimental analysis of their plasmonic resonance and sensing capabilities.

Key methods involved advanced nanofabrication techniques, including electron beam lithography (EBL), UV-Nanoimprint Lithography (UV-NIL) and injection moulding, to create high-resolution periodic arrays. The surface texturing on injection moulded plastic carriers adapts the fabrication to volume production scale. This demonstrates an easy and fast method to manufacture a consumable with the performance matching state-of-the-art (358 nm/RIU). Using this library, it was possible to identify the optimal design for an injection moulded consumable to seamlessly integrate into a commercially available biosensing system for real-time binding kinetic analysis.

A severe condition involving organ dysfunction due to an abnormal immune response called sepsis is reliably diagnosed by the levels of IL-6. Early detection is crucial given the high mortality rate and in this context proof-of-concept LSPR sensor was designed to meet the performance specifications needed for point-of-care applications. Experimental results demonstrated its ability to recognise IL-6 in real time and as a fingerprint detection with high reusability, enhancing both efficiency and affordability.

First published: 1 October 2024

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