{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T10:16:10Z","timestamp":1785406570576,"version":"3.56.0"},"reference-count":61,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T00:00:00Z","timestamp":1783641600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004281","name":"National Science Centre","doi-asserted-by":"publisher","award":["2024\/55\/B\/NZ9\/02690"],"award-info":[{"award-number":["2024\/55\/B\/NZ9\/02690"]}],"id":[{"id":"10.13039\/501100004281","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2024\/55\/B\/NZ9\/02690"],"award-info":[{"award-number":["2024\/55\/B\/NZ9\/02690"]}],"id":[{"id":"https:\/\/ror.org\/03ha2q922","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Hair is an easily obtainable, non-invasive biomatrix that allows for the assessment of long-term physiological responses to environmental and anthropogenic stressors in wildlife populations. Herein, an ultra-high-performance liquid chromatography\u2013electrospray ionization\u2013tandem mass spectrometry (UHPLC-ESI-MS\/MS) method was validated to verify its suitability for the simultaneous determination of cortisol (CORT) and its metabolite, cortisone (CORN), in hair samples collected from wild-living grey wolves (Canis lupus). Hair samples were extracted with methanol and purified using solid-phase extraction on Strata-X cartridges, which enabled effective mitigation of matrix effects. Data for the glucocorticoids were normalized using internal standards. The method demonstrated good linearity for the target stress hormones, with satisfactory precision (RSD &lt; 15%) and limits of quantification of 4.13 pg\/mg for CORT and 2.49 pg\/mg for CORN in the hair matrix. Analysis of authentic wolf hair samples revealed CORT and CORN concentrations in the ranges of &lt;4.13\u201311.86 pg\/mg and &lt;2.49\u20133.67 pg\/mg, respectively. The CORT results showed a strong positive correlation with those obtained using enzymatic immunoassays. The method may be applied to assess the impact of stressors on the welfare of wolves, e.g., providing a useful tool for monitoring recovering European populations as they face new challenges associated with expansion into potentially suboptimal habitats.<\/jats:p>","DOI":"10.3390\/molecules31142420","type":"journal-article","created":{"date-parts":[[2026,7,10]],"date-time":"2026-07-10T09:46:47Z","timestamp":1783676807000},"page":"2420","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Validated LC-MS\/MS Method for Simultaneous Determination of Cortisol and Cortisone in Grey Wolf Hair for Application in Ecological Studies"],"prefix":"10.3390","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-9079-6541","authenticated-orcid":false,"given":"Arkadiusz","family":"Jastrz\u0119bski","sequence":"first","affiliation":[{"name":"Department of Biomedicine and Environmental Research, Institute of Biological Sciences, Faculty of Medicine, The John Paul II Catholic University of Lublin, Konstantyn\u00f3w 1J, 20-708 Lublin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5152-3555","authenticated-orcid":false,"given":"Kinga","family":"O\u017cga-Wybranowska","sequence":"additional","affiliation":[{"name":"Department of Biomedicine and Environmental Research, Institute of Biological Sciences, Faculty of Medicine, The John Paul II Catholic University of Lublin, Konstantyn\u00f3w 1J, 20-708 Lublin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2137-8742","authenticated-orcid":false,"given":"Rafa\u0142","family":"\u0141opucki","sequence":"additional","affiliation":[{"name":"Department of Biomedicine and Environmental Research, Institute of Biological Sciences, Faculty of Medicine, The John Paul II Catholic University of Lublin, Konstantyn\u00f3w 1J, 20-708 Lublin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7771-8032","authenticated-orcid":false,"given":"Sabina","family":"Nowak","sequence":"additional","affiliation":[{"name":"Department of Animal Ecology and Evolution, Institute of Ecology, Faculty of Biology, University of Warsaw, \u017bwirki i Wigury 101, 02-089 Warszawa, Poland"},{"name":"Association for Nature \u201cWolf\u201d, Cynkowa 4, 34-324 Twardorzeczka, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9619-2868","authenticated-orcid":false,"given":"Robert W.","family":"Mys\u0142ajek","sequence":"additional","affiliation":[{"name":"Department of Animal Ecology and Evolution, Institute of Ecology, Faculty of Biology, University of Warsaw, \u017bwirki i Wigury 101, 02-089 Warszawa, Poland"},{"name":"Association for Nature \u201cWolf\u201d, Cynkowa 4, 34-324 Twardorzeczka, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1154-7581","authenticated-orcid":false,"given":"Ilona","family":"Sadok","sequence":"additional","affiliation":[{"name":"Department of Biomedical and Analytical Chemistry, Institute of Biological Sciences, Faculty of Medicine, The John Paul II Catholic University of Lublin, Konstantyn\u00f3w 1J, 20-708 Lublin, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"119888","DOI":"10.1016\/j.cca.2024.119888","article-title":"Cortisol: Biosensing and Detection Strategies","volume":"562","author":"Balasamy","year":"2024","journal-title":"Clin. 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