{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:43:35Z","timestamp":1760222615661,"version":"build-2065373602"},"reference-count":14,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2011,11,28]],"date-time":"2011-11-28T00:00:00Z","timestamp":1322438400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Besides the typical short-lived fluorescence with decay times in the nanosecond range, colloidal II\/VI semiconductor nanoparticles dispersed in buffer also possess a long-lived fluorescence component with decay times in the microsecond range. Here, the signal intensity of the long-lived luminescence at microsecond range is shown to increase 1,000-fold for CdTe nanoparticles in PBS buffer. This long-lived fluorescence can be conveniently employed for time-gated fluorescence detection, which allows for improved signal-to-noise ratio and thus the use of low concentrations of nanoparticles. The detection principle is demonstrated with a time-resolved fluorescence immunoassay for the detection of C-reactive protein (CRP) using CdSe-ZnS nanoparticles and green light excitation.<\/jats:p>","DOI":"10.3390\/s111211335","type":"journal-article","created":{"date-parts":[[2011,11,28]],"date-time":"2011-11-28T11:13:56Z","timestamp":1322478836000},"page":"11335-11342","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Time-Resolved Fluorescence Immunoassay for C-Reactive Protein Using Colloidal Semiconducting Nanoparticles"],"prefix":"10.3390","volume":"11","author":[{"given":"Harri","family":"H\u00e4rm\u00e4","sequence":"first","affiliation":[{"name":"Laboratory of Biophysics, University of Turku, 20520 Turku, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juha","family":"Toivonen","sequence":"additional","affiliation":[{"name":"Laboratory of Biophysics, University of Turku, 20520 Turku, Finland"},{"name":"Department of Physics, Tampere University of Technology, 33101 Tampere, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juhani T.","family":"Soini","sequence":"additional","affiliation":[{"name":"Laboratory of Biophysics, University of Turku, 20520 Turku, Finland"},{"name":"Turku University of Applied Sciences, 20520 Turku, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pekka","family":"H\u00e4nninen","sequence":"additional","affiliation":[{"name":"Laboratory of Biophysics, University of Turku, 20520 Turku, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1672-6650","authenticated-orcid":false,"given":"Wolfgang J.","family":"Parak","sequence":"additional","affiliation":[{"name":"Fachbereich Physik and Wissenschaftliches Zentrum f\u00fcr Materialwissenschaften, Philipps Universit\u00e4t Marburg., 35037 Marburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2011,11,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"H\u00e4nninen, P., and H\u00e4rm\u00e4, H. (2011). Lanthanide Luminescence: Photophysical, Analytical and Biological Aspects. Springer Series on Fluorescence, Springer. Volume 7.","DOI":"10.1007\/978-3-642-21023-5"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1080\/20014091084254","article-title":"Time-resolution in fluorometry technologies, labels, and applications in bioanalytical assays. Critical reviews","volume":"38","author":"Hemmila","year":"2001","journal-title":"Clin. Lab. 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