{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"bioRxiv"}],"indexed":{"date-parts":[[2026,9,22]],"date-time":"2026-09-22T22:09:50Z","timestamp":1790114990486,"version":"4.0.1"},"posted":{"date-parts":[[2026,9,18]]},"group-title":"Biophysics","reference-count":77,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T00:00:00Z","timestamp":1789689600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.biorxiv.org\/about\/FAQ#license"}],"funder":[{"award":["R01GM125995"],"award-info":[{"award-number":["R01GM125995"]}],"id":[{"id":"https:\/\/ror.org\/01cwqze88","id-type":"ROR","asserted-by":"publisher"}]},{"award":["R35GM161252"],"award-info":[{"award-number":["R35GM161252"]}],"id":[{"id":"https:\/\/ror.org\/01cwqze88","id-type":"ROR","asserted-by":"publisher"}]},{"award":["S10 OD012245"],"award-info":[{"award-number":["S10 OD012245"]}],"id":[{"id":"https:\/\/ror.org\/01cwqze88","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,9,18]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:p>\n                  Liquid-state Nuclear Magnetic Resonance (NMR) is an invaluable tool to gain atomic-resolution insights onto molecular structure and dynamics. The impact of NMR spectroscopy, however, is curtailed by high costs and hard-to-maintain high-field magnets. While low-field benchtop NMR spectrometers may address the challenge, severe trade-offs in sensitivity and resolution limit the appeal of this avenue. Here, we introduce a set of novel optically enhanced NMR pulse sequences and procedures (hyperpolarization toolkit) to readily generate\n                  <jats:sup>13<\/jats:sup>\n                  C and\n                  <jats:sup>1<\/jats:sup>\n                  H nuclear-spin hyperpolarization\n                  <jats:italic>in situ<\/jats:italic>\n                  on benchtop spectrometers. This approach leads to unprecedented sensitivity gains, enabling atomic-resolution conformation-dependent detection of a broad range of aromatic compounds, including clinically relevant metabolites and biomarkers. Neurotransmitters including epinephrine, serotonin and melatonin are detected at nanomolar\/micromolar levels by 1D\/2D photochemically-enhanced benchtop NMR in buffer and physiological media including human serum. This advance propels benchtop NMR from a predominantly pedagogical tool to a powerful bioanalytical resource for efficient neurotransmitter identification.\n                <\/jats:p>","DOI":"10.64898\/2026.09.11.751013","type":"posted-content","created":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T20:20:20Z","timestamp":1789762820000},"source":"Crossref","is-referenced-by-count":0,"title":["Hypersensitive Detection of Neurotransmitters in Biological Media by Optically Enhanced Benchtop NMR Spectroscopy"],"prefix":"10.64898","author":[{"given":"Anubhab","family":"Halder","sequence":"first","affiliation":[{"name":"Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI, 53706"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samuel C.","family":"Carey","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI, 53706"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ji Ho","family":"Jeong","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI, 53706"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ummay","family":"Mahfuza Shapla","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI, 53706"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catherine F.M.","family":"Clewett","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI, 53706"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Silvia","family":"Cavagnero","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI, 53706"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026092214500942000_2026.09.11.751013v1.1","doi-asserted-by":"crossref","first-page":"8536","DOI":"10.1021\/acs.analchem.0c01363","article-title":"True picomolar neurotransmitter sensor based on open-ended carbon nanotubes","volume":"92","year":"2020","journal-title":"Anal. 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