Point-of-Care Plasmonic Immunoassay for Early Detection of Heart Failure

In the last decade, there has been a growing demand for sensitive yet affordable point-of-care diagnostic tools that would allow for fast and accurate detection of disease biomarkers. There have been various strategies to improve fluorescent assays performance using nanostructures, but many are not technologically ready to be viable candidates for point-of-care testing (POCT) [1]. Here, we discuss our recent work on the use of a plasmonic enhancement in a POCT microarray immunoassay platform that is compatible with multiplexed detection of biomarkers in both well plate and microfluidic formats [2].<br/><br/>This presentation will cover the development of a plasmonically enhanced POCT immunoassay for heart failure, focusing on key design aspects such as optimizing the assay for multiplexed detection of three heart failure biomarkers (NT-proBNP, NGAL, and Galectin-3), and ensuring compatibility with POCT use. Our plasmonically enhanced immunoassay platform utilizes a fluorescent sandwich antibody assay paired with a custom smartphone-based detector for fast and user-friendly assay quantification. Integration of nanogap plasmonic cavities results in fluorescence brightness enhancement of several hundred-fold and a significant improvement of assay sensitivity. Our plasmonic immunoassay design represents a significant technological leap towards achieving true low-cost, high sensitivity point-of-care testing.<br/><br/>Reference<br/><br/>1. Semeniak, D.; Cruz, D. F.; Chilkoti, A.; Mikkelsen, M. H. Advanced Materials, 35 (34), 2107986 (2023).<br/><br/>2. Cruz, D.F; Fontes, C. M.; Semeniak, D.; Huang, J.; Hucknall, A.; Chilkoti, A.; Mikkelsen, M. H. Nano Letters, 20 (6), 4330-4336 (2020).