{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T23:37:27Z","timestamp":1768520247754,"version":"3.49.0"},"reference-count":37,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,2,2]],"date-time":"2019-02-02T00:00:00Z","timestamp":1549065600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Straight long-range surface plasmon-polariton (LRSPP) waveguides as biosensors for label-free detection are discussed. The sensors consist of 5-\u03bcm-wide 35-nm-thick gold stripes embedded in a low-index optical-grade fluoropolymer (CYTOPTM) with fluidic channels etched to the Au surface of the stripes. This work demonstrates the application of the LRSPP biosensors for the detection of human cardiac troponin I (cTnI) protein. cTnI is a biological marker for acute myocardial infarction (AMI), often referred to as a heart attack, which can be diagnosed by elevated levels of cTnI in patient blood. Direct and sandwich assays were developed and demonstrated over the concentration range from 1 to 1000 ng\/mL, yielding detection limits of 430 pg\/mL for the direct assay and 28 pg\/mL for the sandwich assay (1 standard deviation), the latter being physiologically relevant to the early detection or onset of AMI. In addition, a novel approach for data analysis is proposed, where the analyte response is normalized to the response of the antibody layer.<\/jats:p>","DOI":"10.3390\/s19030631","type":"journal-article","created":{"date-parts":[[2019,2,5]],"date-time":"2019-02-05T11:31:07Z","timestamp":1549366267000},"page":"631","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Long-Range Surface Plasmon-Polariton Waveguide Biosensors for Human Cardiac Troponin I Detection"],"prefix":"10.3390","volume":"19","author":[{"given":"Oleksiy","family":"Krupin","sequence":"first","affiliation":[{"name":"School of Electrical Engineering and Computer Science, University of Ottawa, 800 King Edward Ave., Ottawa, ON K1N 6N5, Canada"},{"name":"Centre for Research in Photonics at the University of Ottawa, University of Ottawa, 25 Templeton, Ottawa, ON K1N 6N5, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pierre","family":"Berini","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering and Computer Science, University of Ottawa, 800 King Edward Ave., Ottawa, ON K1N 6N5, Canada"},{"name":"Centre for Research in Photonics at the University of Ottawa, University of Ottawa, 25 Templeton, Ottawa, ON K1N 6N5, Canada"},{"name":"Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1016\/0021-9673(92)80137-J","article-title":"Biospecific interaction analysis using surface plasmon resonance detection applied to kinetic, binding site and concentration analysis","volume":"597","author":"Fagerstam","year":"1992","journal-title":"J. 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