Plasmonic paper: an emerging analytical platform for highly sensitive biosensors (Conference Presentation)

Abstract

Plasmonic biosensors hold enormous potential for the development of low-cost, label-free, point-of-care biodiagnostics. However, two major challenges need to be overcome to reap the benefits of this class of biosensors: (i) state-of-the-art plasmonic biosensors either offer limited sensitivity or are impractical for real-world applications due to their poor stability and excessive cost; (ii) these biosensors rely on natural antibodies, which are high-cost and impose severe limitations in handling, storage and device integration. We demonstrate that a common filter paper can be transformed into a plasmonic sensing platform for highly sensitive and selective detection of trace levels of chemical and biological analytes. We also demonstrate that short peptides as biorecognition elements compared to larger antibodies as target capture agents offer several advantages. Using a bioplasmonic paper device, we demonstrate the selective and sensitive detection of the cardiac biomarker troponin I. The smaller sized peptide provides higher sensitivity and a lower detection limit using a bioplasmonic paper device. Furthermore, the excellent shelf-life and thermal stability of peptide-based plasmonic biosensors, which precludes the need for special storage conditions, makes it ideal for use in resource-limited settings. We also demonstrate plasmonic biosensors based on artificial antibodies by molecularly imprinting the plasmonic nanotransducers. Apart from significantly lowering the cost, these developments are critical for translating plasmonic sensors to point-of-care and resource-limited settings.