{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T02:49:05Z","timestamp":1768531745346,"version":"3.49.0"},"reference-count":33,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2020,10,21]],"date-time":"2020-10-21T00:00:00Z","timestamp":1603238400000},"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>We describe two novel fluorescent peptides (compounds 1 and 2) targeting oxytocin with a boron-dipyrromethenyl group as the fluorophore bound to an artificial peptide based on the oxytocin receptor, and their application for the analysis of oxytocin levels in human serum using nanometer-sized magnetic beads modified by fluorescent peptides (FMB-1 and FMB-2). Under the optimized experimental protocols, FMB-1 and FMB-2 emitted low levels of fluorescence but emitted much higher levels of fluorescence when associated with oxytocin. The detection limit of oxytocin by FMB-2 was 0.4 pM, which is approximately 37.5 times higher than that of conventional methods, such as ELISA. Using these fluorescent sensors, oxytocin was specifically detected over a wide linear range with high sensitivity, good reusability, stability, precision, and reproducibility. This fluorescent sensor-based detection system thus enabled the measurement of oxytocin levels in human serum, which has widespread applications for oxytocin assays across varied research fields.<\/jats:p>","DOI":"10.3390\/s20205956","type":"journal-article","created":{"date-parts":[[2020,10,22]],"date-time":"2020-10-22T20:51:00Z","timestamp":1603399860000},"page":"5956","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Development of Magnetic Nanobeads Modified by Artificial Fluorescent Peptides for the Highly Sensitive and Selective Analysis of Oxytocin"],"prefix":"10.3390","volume":"20","author":[{"given":"Yoshio","family":"Suzuki","sequence":"first","affiliation":[{"name":"Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"383","DOI":"10.1016\/S0031-9384(03)00151-3","article-title":"Developmental consequences of oxytocin","volume":"79","author":"Carter","year":"2003","journal-title":"Physiol. Behav."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"515","DOI":"10.1097\/AAP.0b013e318266352d","article-title":"Intrathecal oxytocin inhibits visceromotor reflex and spinal neuronal responses to noxious distention of the rat urinary bladder","volume":"37","author":"Engle","year":"2012","journal-title":"Reg. Anesth. Pain Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"152","DOI":"10.1097\/ALN.0b013e318278cd21","article-title":"Reversal of peripheral nerve injury-induced hypersensitivity in the postpartum period role of spinal oxytocin","volume":"118","author":"Gutierrez","year":"2013","journal-title":"Anesthesiology"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1016\/bs.irn.2018.07.007","article-title":"Oxytocin and rodent models of addiction","volume":"140","author":"Leong","year":"2018","journal-title":"Int. Rev. Neurobiol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1016\/j.psyneuen.2015.09.017","article-title":"Local oxytocin tempers anxiety by activating GABAA receptors in the hypothalamic paraventricular nucleus","volume":"63","author":"Smith","year":"2016","journal-title":"Psychoneuroendocrinology"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1016\/j.neuropharm.2018.11.011","article-title":"Oxytocin prevents the increase of cocaine-re-lated responses produced by social defeat","volume":"146","author":"Filarowska","year":"2019","journal-title":"Neuropharmacology"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Bowen, M.T., and Neumann, I.D. (2017). The Multidimensional Therapeutic Potential of Targeting the Brain Oxytocin System for the Treatment of Substance Use Disorders. Behavioral Pharmacology of Neuropeptides: Oxytocin, Springer.","DOI":"10.1007\/7854_2017_17"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1066","DOI":"10.1016\/j.cub.2018.02.044","article-title":"Oxytocin signaling in the lateral septum prevents social fear during lactation","volume":"28","author":"Menon","year":"2018","journal-title":"Curr. Biol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1111\/j.1365-2826.2010.01976.x","article-title":"Oxytocin signal and social behaviour: Comparison among adult and infant oxytocin, oxytocin receptor and CD38 gene knockout mice","volume":"22","author":"Higashida","year":"2010","journal-title":"J. Neuroendocrinol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"589","DOI":"10.1210\/en.2012-1751","article-title":"Coming full circle: Contributions of central and peripheral oxytocin actions to energy balance","volume":"154","author":"Ho","year":"2013","journal-title":"Endocrinology"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"148","DOI":"10.3389\/fnbeh.2019.00148","article-title":"Rodr\u00edguez-Arias, Social housing conditions modulate the long-term increase in cocaine reward induced by intermittent social defeat","volume":"13","author":"Manzanedo","year":"2019","journal-title":"Front. Behav. Neurosci."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"578","DOI":"10.1016\/j.ejphar.2017.11.018","article-title":"Oxytocin inhibited stress induced visceral hypersensitivity, enteric glial cells activation, and release of proin-flammatory cytokines in maternal separated rats","volume":"818","author":"Xu","year":"2018","journal-title":"Eur. J. Pharmacol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1016\/j.jneumeth.2014.01.019","article-title":"Validation of an enzyme-linked immunoassay (ELISA) for plasma oxytocin in a novel mammal species reveals potential errors induced by sampling procedure","volume":"226","author":"Robinson","year":"2014","journal-title":"J. Neurosci. Meth."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"955","DOI":"10.1111\/1440-1681.13267","article-title":"Parasympathetic nervous activity is associated with oxytocin in multiparous, but not primiparous, women during the perinatal period","volume":"47","author":"Washio","year":"2020","journal-title":"Clin. Exp. Pharm. Physiol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1002\/dta.2475","article-title":"Oxytocin analysis from human serum, urine, and saliva by orbitrap liquid chromatography-mass spectrometry","volume":"11","author":"Franke","year":"2019","journal-title":"Drug Test. Anal."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"725","DOI":"10.1016\/j.jpba.2018.11.045","article-title":"Pharmacokinetics, bioavailability and metabolism of cligosiban, an antagonist of oxytocin receptor, in rat by liquid chromatography hyphenated with electrospray ionization tandem mass spectrometry","volume":"164","author":"Yue","year":"2019","journal-title":"J. Pharm. Biomed. Anal."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2659","DOI":"10.1021\/acsnano.9b10163","article-title":"Nanoparticle-Mediated Visualization and Control of Cellular Membrane Potential: Strategies, Progress, and Remaining Issues","volume":"14","author":"Nag","year":"2020","journal-title":"ACS Nano"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"440","DOI":"10.1002\/bio.3790","article-title":"Recent advances in fluorescence sensors based on DNA-MOF hybrids","volume":"35","author":"Wu","year":"2020","journal-title":"Luminescence"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"290","DOI":"10.1016\/j.snb.2018.12.024","article-title":"Facile preparation and application of luminescent cucurbit[10]uril-based porous supramolecular frameworks","volume":"283","author":"Liu","year":"2019","journal-title":"Sens. Actutors Chem."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"44696","DOI":"10.1021\/acsami.8b14215","article-title":"Excited-State Intramolecular Proton Transfer-Based Multifunctional Solid-State Emitter: A Fluorescent Platform with \u201cWrite-Erase-Write\u201d Function","volume":"10","author":"Pallavi","year":"2018","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"4709","DOI":"10.1021\/cr900323b","article-title":"Binary probes for nucleic acid analysis","volume":"110","author":"Kolpashchikov","year":"2010","journal-title":"Chem. Rev."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"797","DOI":"10.1038\/nmeth.1242","article-title":"Single-spike detection in vitro and in vivo with a genetic Ca2+ sensor","volume":"5","author":"Wallace","year":"2008","journal-title":"Nat. Methods"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"17799","DOI":"10.1021\/ja054739q","article-title":"Design and synthesis of intramolecular charge transfer-based fluorescent reagents for the highly sensitive detection of proteins","volume":"127","author":"Suzuki","year":"2005","journal-title":"J. Am. Chem. Soc."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"15137","DOI":"10.1039\/C9CC07492A","article-title":"Switching to a \u201cturn-on\u201d fluorescent probe for selective monitoring of cyanide in food samples and living systems","volume":"55","author":"Wu","year":"2019","journal-title":"Chem. Commun."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Chen, S., Xue, Z.X., Gao, N., Yang, X.M., and Zang, L. (2020). Perylene Diimide-Based Fluorescent and Colorimetric Sensors for Environmental Detection. Sensors, 20.","DOI":"10.3390\/s20030917"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2480","DOI":"10.1039\/C8AN01801D","article-title":"Fluorescent organic nanoparticles (FONs) as convenient probes for metal ion detection in aqueous medium","volume":"144","author":"Ahmed","year":"2019","journal-title":"Analyst"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1016\/j.aca.2020.01.057","article-title":"Chemo- and biosensing applications of spiropyran and its derivatives A review","volume":"1110","author":"Ali","year":"2020","journal-title":"Anal. Chim. Acta"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1016\/j.snb.2017.07.080","article-title":"Development of a Fluorescent Peptide for the Highly Sensitive and Selective Detection of Oxytocin","volume":"254","author":"Suzuki","year":"2018","journal-title":"Sens. Actutors B Chem."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"496","DOI":"10.1039\/b617972j","article-title":"The chemistry of Bodipy: A new El Dorado for fluorescence tools","volume":"31","author":"Ziessel","year":"2007","journal-title":"New J. Chem."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1184","DOI":"10.1002\/anie.200702070","article-title":"The chemistry of fluorescent Bodipy dyes: Versatility unsurpassed","volume":"47","author":"Ulrich","year":"2008","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"526","DOI":"10.1038\/356526a0","article-title":"Structure and expression of a human oxytocin receptor","volume":"356","author":"Kimura","year":"1992","journal-title":"Nature"},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Suzuki, Y. (2019). Development of Fluorescent Reagent Based on Ligand Exchange Reaction for Highly Sensitive and Selective Detection of Dopamine in the Serum. Sensors, 19.","DOI":"10.3390\/s19183928"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"26","DOI":"10.1016\/j.infbeh.2015.06.007","article-title":"Explicit and Implicit Caregiving Interests in Expectant Fathers: Do Endogenous and Exogenous Oxytocin and Vasopressin Matter?","volume":"41","author":"Bendahan","year":"2015","journal-title":"Infant Behav."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/20\/5956\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:25:25Z","timestamp":1760178325000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/20\/5956"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,10,21]]},"references-count":33,"journal-issue":{"issue":"20","published-online":{"date-parts":[[2020,10]]}},"alternative-id":["s20205956"],"URL":"https:\/\/doi.org\/10.3390\/s20205956","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,10,21]]}}}