{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T19:35:33Z","timestamp":1790883333494,"version":"4.1.0"},"reference-count":93,"publisher":"Wiley","issue":"19","license":[{"start":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T00:00:00Z","timestamp":1773014400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T00:00:00Z","timestamp":1773014400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Small"],"published-print":{"date-parts":[[2026,4]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>Localized surface plasmon resonance (LSPR) biosensing offers label\u2010free, real\u2010time detection of biomolecular interactions with high sensitivity and compact instrumentation. However, despite widespread use, several persistent and poorly understood phenomena limit the reproducibility, quantitation, and interpretability of LSPR signals. This perspective examines six recurring \u201cconundrums\u201d in LSPR biosensing, with a focus on their physical origins, experimental manifestations, and current approaches to mitigation. I review puzzling cases where analyte binding induces either red or blueshifts of the plasmon resonance; the difficulty of isolating the surface\u2010confined signal from bulk refractive\u2010index drift in microfluidics; the finite decay length of the plasmon field and the resulting saturation for thick or inhomogeneous layers; environmental cross\u2010sensitivities to temperature, pH, and ionic strength; run\u2010to\u2010run variability in nanostructure fabrication; and spectral congestion in multiplexed measurements. For each, I discuss the state of understanding, identify open questions, and outline strategies from advanced optical readouts to algorithmic baseline correction that could enable truly quantitative, drift\u2010immune, and reproducible LSPR\u00a0biosensing.<\/jats:p>","DOI":"10.1002\/smll.202513520","type":"journal-article","created":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T09:36:43Z","timestamp":1773049003000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Conundrums of Localized Surface Plasmon Resonance Biosensors"],"prefix":"10.1002","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4720-3679","authenticated-orcid":false,"given":"Nikhil","family":"Bhalla","sequence":"first","affiliation":[{"name":"Nanotechnology and Integrated Bioengineering Centre (NIBEC), School of Engineering Ulster University 2\u201024 York Street Belfast \u00a0BT15 1AP United\u00a0Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,3,9]]},"reference":[{"key":"e_1_2_10_2_1","doi-asserted-by":"publisher","DOI":"10.1021\/cr068107d"},{"key":"e_1_2_10_3_1","doi-asserted-by":"publisher","DOI":"10.1021\/cr100313v"},{"key":"e_1_2_10_4_1","doi-asserted-by":"publisher","DOI":"10.1038\/nmat2162"},{"key":"e_1_2_10_5_1","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.physchem.58.032806.104607"},{"key":"e_1_2_10_6_1","unstructured":"Tem5psu. \u201cIllustration of the Localized Surface Plasmon Resonance of a Metal Nanoparticle in an Oscillating Electric Field (\u201cNanoparticle Lspr 2.png\u201d) \u201dhttps:\/\/commons.wikimedia.org\/wiki\/File:Nanoparticle_lspr_2.png#\/media\/File:Nanoparticle_lspr_2.png 2015 licensed under CC BY\u2010SA 4.0."},{"key":"e_1_2_10_7_1","doi-asserted-by":"publisher","DOI":"10.3390\/s21062111"},{"key":"e_1_2_10_8_1","doi-asserted-by":"publisher","DOI":"10.1186\/1556-276X-9-187"},{"key":"e_1_2_10_9_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cclet.2017.09.003"},{"key":"e_1_2_10_10_1","doi-asserted-by":"publisher","DOI":"10.1021\/ja020393x"},{"issue":"3","key":"e_1_2_10_11_1","first-page":"244","article-title":"Lspr Biosensors: A Review on Recent Advances","volume":"4","author":"Sep\u00falveda B.","year":"2009","journal-title":"Nano Today"},{"key":"e_1_2_10_12_1","doi-asserted-by":"publisher","DOI":"10.1038\/nphoton.2012.266"},{"key":"e_1_2_10_13_1","doi-asserted-by":"publisher","DOI":"10.1039\/D3NA01131C"},{"key":"e_1_2_10_14_1","doi-asserted-by":"publisher","DOI":"10.1021\/acs.nanolett.4c03159"},{"key":"e_1_2_10_15_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467-023-40153-9"},{"key":"e_1_2_10_16_1","doi-asserted-by":"publisher","DOI":"10.1126\/sciadv.adp3353"},{"key":"e_1_2_10_17_1","doi-asserted-by":"publisher","DOI":"10.1002\/adbi.201700258"},{"key":"e_1_2_10_18_1","doi-asserted-by":"publisher","DOI":"10.1021\/acs.analchem.9b03780"},{"key":"e_1_2_10_19_1","doi-asserted-by":"publisher","DOI":"10.1021\/acssensors.8b00287"},{"key":"e_1_2_10_20_1","doi-asserted-by":"publisher","DOI":"10.1021\/acssensors.1c02722"},{"key":"e_1_2_10_21_1","doi-asserted-by":"publisher","DOI":"10.3390\/bios11120527"},{"issue":"12","key":"e_1_2_10_22_1","doi-asserted-by":"crossref","first-page":"4428","DOI":"10.1021\/nl902721z","article-title":"Refractometric Sensing Using Propagating Versus Localized Surface Plasmons: A direct comparison","volume":"9","author":"Svedendahl M.","year":"2009","journal-title":"Nano Letters"},{"issue":"13","key":"e_1_2_10_23_1","first-page":"3613","article-title":"Nanoplasmonic Sensors for Biointerfacial Science","volume":"48","author":"Jackman J. 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