{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T15:58:46Z","timestamp":1791302326879,"version":"4.1.0"},"reference-count":36,"publisher":"American Chemical Society (ACS)","issue":"39","license":[{"start":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T00:00:00Z","timestamp":1790121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["1833656"],"award-info":[{"award-number":["1833656"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"National Science Foundation","doi-asserted-by":"publisher","award":["2306334"],"award-info":[{"award-number":["2306334"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,6]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Emetine is a biologically active isoquinoline alkaloid with reported antiviral, anticancer, and antiparasitic properties; however, its broader therapeutic application remains limited by dose-dependent toxicity and an incomplete understanding of its oxidative behavior. The electrochemical oxidation of emetine at a glassy carbon electrode (GCE) under physiologically relevant conditions was investigated using cyclic voltammetry (CV), differential pulse voltammetry (DPV), controlled-potential electrolysis (CPE), UV\u2013Vis and fluorescence spectroscopy, and high-resolution LC\u2013QTOF\u2013MS\/MS. DPV revealed three irreversible anodic oxidation processes centered near +0.90, +1.01, and +1.25 V versus Ag\/AgCl. Scan-rate studies showed that the two lower-potential processes are predominantly diffusion-controlled, whereas the higher-potential process exhibits greater contributions from surface-associated and interfacial phenomena. pH-dependent studies (pH 4.0\u20139.1) demonstrated that emetine oxidation is strongly influenced by the protonation state and proceeds through a complex multistep irreversible mechanism. CPE generated multiple oxidation products, and subsequent high-resolution LC\u2013QTOF\u2013MS\/MS analysis revealed ten emetine-associated products (P1\u2013P10). Tentative structural assignments for P1\u2013P8 encompassed dehydrogenated, oxygenated\/dehydrogenated, and nitrogen-containing products, whereas P9 and P10 remained structurally unresolved. Together with complementary spectroscopic evidence, these findings support a mechanistic model in which emetine oxidation is initiated at amine functionalities and adjacent benzylic carbon centers, followed by competing dehydrogenation, oxygen incorporation, and secondary product-forming reactions. This study establishes a mechanistic framework for emetine electrooxidation and demonstrates the utility of integrating electrochemistry with high-resolution mass spectrometry to investigate the oxidative chemistry of bioactive isoquinoline alkaloids.<\/jats:p>","DOI":"10.1021\/acsomega.6c06393","type":"journal-article","created":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T14:02:13Z","timestamp":1790172133000},"page":"59735-59753","source":"Crossref","is-referenced-by-count":0,"title":["Electrochemical\nInvestigation of the Redox Behavior\nof Isoquinoline Alkaloid Emetine"],"prefix":"10.1021","volume":"11","author":[{"given":"Carin","family":"Smith","sequence":"first","affiliation":[{"name":"University of the District of Columbia , , , ,","place":["Washington, District of Columbia, United States, 20008"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"JaVe","family":"Bonner","sequence":"additional","affiliation":[{"name":"University of the District of Columbia , , , ,","place":["Washington, District of Columbia, United States, 20008"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emah","family":"Assimewlui","sequence":"additional","affiliation":[{"name":"University of the District of Columbia , , , ,","place":["Washington, District of Columbia, United States, 20008"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keliah","family":"Tucker","sequence":"additional","affiliation":[{"name":"University of the District of Columbia , , , ,","place":["Washington, District of Columbia, United States, 20008"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Esdrizabeth","family":"Pereyra Cuello","sequence":"additional","affiliation":[{"name":"University of the District of Columbia , , , ,","place":["Washington, District of Columbia, United States, 20008"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cassandra","family":"Sellers","sequence":"additional","affiliation":[{"name":"University 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University , , , ,","place":["Washington, District of Columbia, United States, 20059"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oladapo","family":"Bakare","sequence":"additional","affiliation":[{"name":"Howard University , , , ,","place":["Washington, District of Columbia, United States, 20059"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1874-2999","authenticated-orcid":true,"given":"Yue","family":"Li","sequence":"additional","affiliation":[{"name":"University of Maryland , , , ,","place":["College Park, Maryland, United States, 20742"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0575-5085","authenticated-orcid":true,"given":"Uche","family":"Udeochu","sequence":"additional","affiliation":[{"name":"University of the District of Columbia , , , ,","place":["Washington, District of Columbia, United States, 20008"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,9,23]]},"reference":[{"issue":"1","key":"2026100610493796500_cit1","doi-asserted-by":"publisher","DOI":"10.1038\/s41420-024-01967-8","article-title":"Emetine Induces\nOxidative Stress, Cell Differentiation and NF-\u039aB Inhibition,\nSuppressing AML Stem\/Progenitor Cells","volume":"10","author":"Silva","year":"2024","journal-title":"Cell\nDeath Discovery"},{"issue":"1","key":"2026100610493796500_cit2","doi-asserted-by":"publisher","DOI":"10.1038\/s41421-018-0034-1","article-title":"Emetine Inhibits Zika\nand Ebola Virus Infections through Two Molecular Mechanisms: Inhibiting\nViral Replication and Decreasing Viral Entry","volume":"4","author":"Yang","year":"2018","journal-title":"Cell Discovery"},{"issue":"17","key":"2026100610493796500_cit3","doi-asserted-by":"publisher","first-page":"7450","DOI":"10.1021\/jm300426q","article-title":"Design, Synthesis, and Evaluation of PH-Dependent Hydrolyzable\nEmetine Analogues as Treatment for Prostate Cancer","volume":"55","author":"Akinboye","year":"2012","journal-title":"J. Med. Chem."},{"key":"2026100610493796500_cit4","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1080\/10408347.2025.2529458","article-title":"Emetine: Advances\nin Pharmacology, Toxicology, and Chromatographic Approaches","author":"Gebrehiwot","year":"2025","journal-title":"Crit. Rev. Anal. Chem."},{"issue":"12","key":"2026100610493796500_cit5","doi-asserted-by":"publisher","DOI":"10.26508\/lsa.202201560","article-title":"Emetine Blocks DNA Replication via\nProteosynthesis Inhibition Not by Targeting Okazaki Fragments","volume":"5","author":"Lukac","year":"2022","journal-title":"Life Sci. Alliance"},{"issue":"1","key":"2026100610493796500_cit6","doi-asserted-by":"publisher","first-page":"105","DOI":"10.1016\/0002-8703(74)90397-4","article-title":"The Correlation\nof Metabolic and\nUltrastructural Changes in Emetine Myocardial Toxicity","volume":"87","author":"Murphy","year":"1974","journal-title":"Am. 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