{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T15:33:41Z","timestamp":1785252821890,"version":"3.55.0"},"reference-count":37,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,4,6]],"date-time":"2018-04-06T00:00:00Z","timestamp":1522972800000},"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>Integrating multi-responsive polymers such as microgels onto optical fiber tips, in a controlled fashion, enables unprecedented functionalities to Lab-on-fiber optrodes. The creation of a uniform microgel monolayer with a specific coverage factor is crucial for enhancing the probes responsivity to a pre-defined target parameter. Here we report a reliable fabrication strategy, based on the dip coating technique, for the controlled realization of microgel monolayer onto unconventional substrates, such as the optical fiber tip. The latter was previously covered by a plasmonic nanostructure to make it sensitive to superficial environment changes. Microgels have been prepared using specific Poly(N-isopropylacrylamide)-based monomers that enable bulky size changes in response to both temperature and pH variations. The formation of the microgel monolayer is efficiently controlled through the selection of suitable operating pH, temperature and concentration of particle dispersions used during the dipping procedure. The effect of each parameter has been evaluated, and the validity of our procedure is confirmed by means of both morphological and optical characterizations. We demonstrate that when the coverage factor exceeds 90%, the probe responsivity to microgels swelling\/collapsing is significantly improved. Our study opens new paradigms for the development of engineered microgels assisted Lab-on-Fiber probes for biochemical applications.<\/jats:p>","DOI":"10.3390\/s18041119","type":"journal-article","created":{"date-parts":[[2018,4,10]],"date-time":"2018-04-10T13:06:08Z","timestamp":1523365568000},"page":"1119","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Optimization Strategies for Responsivity Control of Microgel Assisted Lab-On-Fiber Optrodes"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5010-3604","authenticated-orcid":false,"given":"Martino","family":"Giaquinto","sequence":"first","affiliation":[{"name":"Optoelectronics Group, Department of Engineering, University of Sannio, I-82100 Benevento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Micco","sequence":"additional","affiliation":[{"name":"Optoelectronics Group, Department of Engineering, University of Sannio, I-82100 Benevento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Aliberti","sequence":"additional","affiliation":[{"name":"Optoelectronics Group, Department of Engineering, University of Sannio, I-82100 Benevento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eugenia","family":"Bobeico","sequence":"additional","affiliation":[{"name":"ENEA, Portici Research Center, P. le E. Fermi 1, Portici, I-80055 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vera","family":"La Ferrara","sequence":"additional","affiliation":[{"name":"ENEA, Portici Research Center, P. le E. Fermi 1, Portici, I-80055 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Menotti","family":"Ruvo","sequence":"additional","affiliation":[{"name":"Institute of Biostructure and Bioimaging, National Research Council, I-80143 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4025-7890","authenticated-orcid":false,"given":"Armando","family":"Ricciardi","sequence":"additional","affiliation":[{"name":"Optoelectronics Group, Department of Engineering, University of Sannio, I-82100 Benevento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Cusano","sequence":"additional","affiliation":[{"name":"Optoelectronics Group, Department of Engineering, University of Sannio, I-82100 Benevento, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"922","DOI":"10.1002\/lpor.201600111","article-title":"Lab on fiber technology for biological sensing applications","volume":"10","author":"Vaiano","year":"2016","journal-title":"Laser Photonics Rev."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Cusano, A., Consales, M., Crescitelli, A., and Ricciardi, A. 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