{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T12:05:12Z","timestamp":1790251512513,"version":"4.1.0"},"reference-count":29,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T00:00:00Z","timestamp":1790208000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>A robust liquid chromatography tandem mass spectrometry (LC\u2013MS\/MS) method was developed and validated for determining erythromycin A (ERY A) and its metabolites: erythromycin B (ERY B), erythromycin C (ERY C), erythromycin A N-oxide (ENO), anhydroerythromycin A (AHEA), N-demethylerythromycin A (NDEA), erythromycin A enol ether (EAEE), and pseudoerythromycin A enol ether (PSEE) in salmon muscle with skin. Tissue samples (1.00 g) fortified with ERY A, ERY B, ERY C, ENO, EAEE, and PSEE at 50\u2013200 ng\/g and AHEA and NDEA at 500\u20132000 ng\/g, using a surrogate internal standard, were extracted with acetonitrile, defatted hexane, and diluted water, resulting in accuracy from 87% to 108%, precision from 3% to 13%, and estimated LOQ from 0.02 to 1.2 ng\/g. Incurred salmon showed ERY A as the major residue at 3 days post-administration and NDEA and AHEA as potential markers exceeding the 500 ng\/g level on Day 28.<\/jats:p>","DOI":"10.3390\/molecules31193406","type":"journal-article","created":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T11:11:23Z","timestamp":1790248283000},"page":"3406","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Development of an LC\u2013MS\/MS Method for Simultaneous Quantification of Erythromycin A and Seven Metabolites: Initial Residue Profile in Salmon Muscle with Skin"],"prefix":"10.3390","volume":"31","author":[{"given":"Chaitali","family":"Chattopadhaya","sequence":"first","affiliation":[{"name":"Division of Residue Chemistry, Office of Applied Science, Center for Veterinary Medicine, U.S. Food and Drug Administration (FDA), Laurel, MD 20708, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-4343-4863","authenticated-orcid":false,"given":"Sean","family":"Knutson","sequence":"additional","affiliation":[{"name":"Division of Residue Chemistry, Office of Applied Science, Center for Veterinary Medicine, U.S. Food and Drug Administration (FDA), Laurel, MD 20708, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Hernando","family":"Escobar Loaiza","sequence":"additional","affiliation":[{"name":"Division of Residue Chemistry, Office of Applied Science, Center for Veterinary Medicine, U.S. Food and Drug Administration (FDA), Laurel, MD 20708, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5130-5758","authenticated-orcid":false,"given":"Kenneth M.","family":"Taylor","sequence":"additional","affiliation":[{"name":"Division of Residue Chemistry, Office of Applied Science, Center for Veterinary Medicine, U.S. Food and Drug Administration (FDA), Laurel, MD 20708, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"project-administration","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Charles","family":"Gieseker","sequence":"additional","affiliation":[{"name":"Division of Residue Chemistry, Office of Applied Science, Center for Veterinary Medicine, U.S. Food and Drug Administration (FDA), Laurel, MD 20708, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"resources","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Pak-Sin","family":"Chu","sequence":"additional","affiliation":[{"name":"Division of Residue Chemistry, Office of Applied Science, Center for Veterinary Medicine, U.S. Food and Drug Administration (FDA), Laurel, MD 20708, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e893","DOI":"10.1016\/S2542-5196(21)00280-1","article-title":"Global antibiotic consumption and usage in humans, 2000\u20132018: A spatial modelling study","volume":"5","author":"Browne","year":"2021","journal-title":"Lancet Planet Health"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"483","DOI":"10.1016\/j.envres.2018.11.040","article-title":"Human health risk assessment of antibiotic resistance associated with antibiotic residues in the environment: A review","volume":"169","author":"Ben","year":"2019","journal-title":"Environ. 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