{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T15:15:18Z","timestamp":1788362118419,"version":"build-2803163510"},"reference-count":40,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T00:00:00Z","timestamp":1788307200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>Background\/Objectives: Saliva may provide a non-invasive alternative to blood sampling for therapeutic drug monitoring (TDM) of mycophenolic acid (MPA) in children. This study assessed MPA and, secondarily, mycophenolic acid glucuronide (MPAG) in non-centrifuged Salivette\u00ae devices to determine an acceptable interval between saliva collection and laboratory processing. Methods: Phosphate-buffered saline (PBS), artificial saliva, and saliva from five healthy adult volunteers were externally spiked with MPA and MPAG at 5 and 500 ng\/mL and applied to Salivette\u00ae cotton swabs. Samples were stored for 12, 24, and 48 h at 22 \u00b0C and 6 \u00b0C and analyzed by liquid chromatography-tandem mass spectrometry. Percentage deviations from nominal concentration within \u00b115% were considered acceptable. Results: In PBS, both analytes met the acceptance criterion for up to 24 h under both conditions. In artificial saliva, both met the criterion for at least 24 h and, under some conditions, for 48 h. In human saliva, all volunteer-level MPA results met the criterion after 12 h at both temperatures, whereas MPAG did not consistently meet it. Mean MPA deviations across volunteers ranged from \u221210.8 to 1.9% at 22 \u00b0C and from \u221212.3 to 2.4% at 6 \u00b0C. Conclusions: MPA met the acceptance criterion after 12-h in non-centrifuged Salivette\u00ae devices, supporting the feasibility of a 12-h pre-centrifugation interval under comparable conditions. Prompt centrifugation and processing are advisable when MPAG determination is required. Confirmation using incurred post-dose saliva from pediatric patients receiving mycophenolate mofetil is required.<\/jats:p>","DOI":"10.3390\/pharmaceutics18091106","type":"journal-article","created":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T14:35:29Z","timestamp":1788359729000},"page":"1106","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Pre-Analytical Stability of Mycophenolic Acid and Its Glucuronide in Saliva Samples Stored in Cotton Salivette\u00ae Devices Before Centrifugation"],"prefix":"10.3390","volume":"18","author":[{"given":"Grzegorz","family":"Szynkaruk","sequence":"first","affiliation":[{"name":"The Student Scientific Society of Poznan, University of Medical Sciences, 5 Rokietnicka Street, 60-806 Poznan, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Julia","family":"Kerner","sequence":"additional","affiliation":[{"name":"The Student Scientific Society of Poznan, University of Medical Sciences, 5 Rokietnicka Street, 60-806 Poznan, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Ahata","family":"Nelipovich","sequence":"additional","affiliation":[{"name":"The Student Scientific Society of Poznan, University of Medical Sciences, 5 Rokietnicka Street, 60-806 Poznan, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-2533-022X","authenticated-orcid":false,"given":"Kacper","family":"Osuch","sequence":"additional","affiliation":[{"name":"The Student Scientific Society of Poznan, University of Medical Sciences, 5 Rokietnicka Street, 60-806 Poznan, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Maria","family":"Miotk","sequence":"additional","affiliation":[{"name":"The Student Scientific Society of Poznan, University of Medical Sciences, 5 Rokietnicka Street, 60-806 Poznan, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Agata","family":"Bartkowiak","sequence":"additional","affiliation":[{"name":"The Student Scientific Society of Poznan, University of Medical Sciences, 5 Rokietnicka Street, 60-806 Poznan, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2764-1575","authenticated-orcid":false,"given":"Joanna","family":"Sobiak","sequence":"additional","affiliation":[{"name":"Department of Physical Pharmacy and Pharmacokinetics, Poznan University of Medical Sciences, 3 Rokietnicka Street, 60-806 Poznan, Poland"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1097\/FTD.0000000000000871","article-title":"Personalized Therapy for Mycophenolate: Consensus Report by the International Association of Therapeutic Drug Monitoring and Clinical Toxicology","volume":"43","author":"Bergan","year":"2021","journal-title":"Ther. 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