{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T13:20:03Z","timestamp":1788441603353,"version":"build-2803163510"},"reference-count":40,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2025,6,27]],"date-time":"2025-06-27T00:00:00Z","timestamp":1750982400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Estrogens are potent hormones involved in numerous physiological and pathological processes. Their typically low concentrations in biological samples necessitate highly sensitive analytical methods for accurate quantification. This study presents a high-performance liquid chromatography with fluorescence detection (HPLC-FLD) method for quantifying estradiol and its metabolites in blood serum and saliva. Analytes were extracted using solid-phase microextraction with a divinylbenzene sorbent and methanol as the desorption agent. FLD was performed after the derivatization of the analytes with dansyl chloride. Separation was achieved on a Poroshell 120 EC-C18 column (2.1 \u00d7 100 mm, 2.7 \u00b5m) at 50 \u00b0C using water with 0.1% formic acid and methanol as the mobile phase at 0.5 mL\/min. A gradient elution increased the methanol concentration from 76% to 100% over 0\u20138 min, then it returned to 76% at 8.1 min and was held until 11 min had passed. Detection was at \u03bbEX 350 nm and \u03bbEM 530 nm. Good linearity was observed for estradiol, 2-hydroxyestradiol, and 2-methoxyestradiol (10\u2013300 ng\/mL; R2 = 0.9893\u20130.9995). The LOQ for all analytes was 10 ng\/mL. Solid-phase microextraction (SPME) offered advantages over liquid\u2013liquid extraction. The method is suitable for quantifying estrogens in the 10 ng\/mL\u20131 \u00b5g\/mL range.<\/jats:p>","DOI":"10.3390\/ijms26136194","type":"journal-article","created":{"date-parts":[[2025,6,27]],"date-time":"2025-06-27T05:29:58Z","timestamp":1751002198000},"page":"6194","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Development of an HPLC-FLD Method for Estradiol and Metabolites: Application of Solid-Phase Microextraction"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6545-9822","authenticated-orcid":false,"given":"Anna","family":"Kaliszewska","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Medical University of Gda\u0144sk, Hallera 107, 80-416 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Piotr","family":"Struczy\u0144ski","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Medical University of Gda\u0144sk, Hallera 107, 80-416 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomasz","family":"B\u0105czek","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Medical University of Gda\u0144sk, Hallera 107, 80-416 Gda\u0144sk, Poland"},{"name":"Department of Nursing and Medical Rescue, Institute of Health Sciences, Pomeranian University in S\u0142upsk, 76-200 S\u0142upsk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1015-0478","authenticated-orcid":false,"given":"Lucyna","family":"Konieczna","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Medical University of Gda\u0144sk, Hallera 107, 80-416 Gda\u0144sk, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1093\/oxfordjournals.epirev.a036115","article-title":"Reproductive factors and breast cancer","volume":"15","author":"Kelsey","year":"1993","journal-title":"Epidemiol. 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