001055046 001__ 1055046 001055046 005__ 20260225202306.0 001055046 0247_ $$2doi$$a10.3390/analytica7010015 001055046 0247_ $$2datacite_doi$$a10.34734/FZJ-2026-01838 001055046 037__ $$aFZJ-2026-01838 001055046 082__ $$a540 001055046 1001_ $$0P:(DE-Juel1)196963$$aJonas, Alissa$$b0$$ufzj 001055046 245__ $$aDevelopment and Validation of an UHPLC-ESI-QTOF-MS Method According to the ICH M10 Guideline for Quantification of the Clinical Drug Candidate RD2 in the Mouse Brain 001055046 260__ $$aBasel$$bMDPI$$c2026 001055046 3367_ $$2DRIVER$$aarticle 001055046 3367_ $$2DataCite$$aOutput Types/Journal article 001055046 3367_ $$0PUB:(DE-HGF)16$$2PUB:(DE-HGF)$$aJournal Article$$bjournal$$mjournal$$s1771997333_12427 001055046 3367_ $$2BibTeX$$aARTICLE 001055046 3367_ $$2ORCID$$aJOURNAL_ARTICLE 001055046 3367_ $$00$$2EndNote$$aJournal Article 001055046 520__ $$aThe all-D-enantiomeric-peptide RD2 was developed for the treatment of Alzheimer’s disease. This study aimed to develop a specific and highly sensitive liquid chromatographymass-spectrometric (UHPLC-ESI-QTOF) method for quantifying RD2 in the mouse brainand to validate it according to the ICH M10 guideline to investigate the pharmacokinetic profile of RD2 in its target organ. Sample preparation, chromatographic separation and quantification were very challenging due to RD2’s highly hydrophilic properties, the complex matrix and the required lower limit of quantification (LLOQ). Chromatographic separation was performed on an Acquity UPLC BEH C18 column (2.1 × 100 mm, 1.7 μm particle size) within 5 min at 50 ◦C with a flow rate of 0.5 mL·min−1. Mobile phasesconsisted of water and acetonitrile with 0.2% formic acid and 0.015% heptafluorobutyric acid. Ions were generated by electrospray ionization in the positive mode, and RD2 was quantified by QTOF-MS. The developed extraction method revealed complete recovery.The linearity of the calibration curve was in the range of 2 ng·mL−1 to 500 ng·mL−1 (R2 > 0.99) with a LLOQ of 5 ng·mL−1. The intraday and interday accuracy and precision ranged from 0.4% to 12.2% and from 1.0% to 12.0%. RD2 remained stable in thefreshly homogenized brain even after several freeze–thaw cycles, but stability decreased over time during long-term storage at −80 ◦C. Using this validated method, RD2-spiked brain homogenate samples and samples of a pharmacokinetic study with RD2 in micewere analyzed. 001055046 536__ $$0G:(DE-HGF)POF4-5244$$a5244 - Information Processing in Neuronal Networks (POF4-524)$$cPOF4-524$$fPOF IV$$x0 001055046 588__ $$aDataset connected to CrossRef, Journals: juser.fz-juelich.de 001055046 7001_ $$0P:(DE-Juel1)171922$$aGering, Ian$$b1 001055046 7001_ $$0P:(DE-Juel1)166069$$aSchartmann, Elena$$b2 001055046 7001_ $$0P:(DE-Juel1)165908$$aSchemmert, Sarah$$b3 001055046 7001_ $$0P:(DE-Juel1)132029$$aWillbold, Dieter$$b4 001055046 7001_ $$0P:(DE-Juel1)133853$$aSantiago-Schübel, Beatrix$$b5 001055046 7001_ $$0P:(DE-Juel1)159137$$aKutzsche, Janine$$b6$$eCorresponding author 001055046 773__ $$0PERI:(DE-600)3035770-6$$a10.3390/analytica7010015$$gVol. 7, no. 1, p. 15 -$$n1$$p15 -$$tAnalytica$$v7$$x2673-4532$$y2026 001055046 8564_ $$uhttps://juser.fz-juelich.de/record/1055046/files/analytica-07-00015-v2.pdf$$yOpenAccess 001055046 909CO $$ooai:juser.fz-juelich.de:1055046$$popenaire$$popen_access$$pVDB$$pdriver$$pdnbdelivery 001055046 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)196963$$aForschungszentrum Jülich$$b0$$kFZJ 001055046 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)171922$$aForschungszentrum Jülich$$b1$$kFZJ 001055046 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)132029$$aForschungszentrum Jülich$$b4$$kFZJ 001055046 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)133853$$aForschungszentrum Jülich$$b5$$kFZJ 001055046 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)159137$$aForschungszentrum Jülich$$b6$$kFZJ 001055046 9131_ $$0G:(DE-HGF)POF4-524$$1G:(DE-HGF)POF4-520$$2G:(DE-HGF)POF4-500$$3G:(DE-HGF)POF4$$4G:(DE-HGF)POF$$9G:(DE-HGF)POF4-5244$$aDE-HGF$$bKey Technologies$$lNatural, Artificial and Cognitive Information Processing$$vMolecular and Cellular Information Processing$$x0 001055046 9141_ $$y2026 001055046 915__ $$0StatID:(DE-HGF)0200$$2StatID$$aDBCoverage$$bSCOPUS$$d2025-11-11 001055046 915__ $$0LIC:(DE-HGF)CCBY4$$2HGFVOC$$aCreative Commons Attribution CC BY 4.0 001055046 915__ $$0StatID:(DE-HGF)0600$$2StatID$$aDBCoverage$$bEbsco Academic Search$$d2025-11-11 001055046 915__ $$0StatID:(DE-HGF)0112$$2StatID$$aWoS$$bEmerging Sources Citation Index$$d2025-11-11 001055046 915__ $$0StatID:(DE-HGF)0501$$2StatID$$aDBCoverage$$bDOAJ Seal$$d2023-04-12T14:55:21Z 001055046 915__ $$0StatID:(DE-HGF)0500$$2StatID$$aDBCoverage$$bDOAJ$$d2023-04-12T14:55:21Z 001055046 915__ $$0StatID:(DE-HGF)0150$$2StatID$$aDBCoverage$$bWeb of Science Core Collection$$d2025-11-11 001055046 915__ $$0StatID:(DE-HGF)0510$$2StatID$$aOpenAccess 001055046 915__ $$0StatID:(DE-HGF)0030$$2StatID$$aPeer Review$$bASC$$d2025-11-11 001055046 915__ $$0StatID:(DE-HGF)0561$$2StatID$$aArticle Processing Charges$$d2025-11-11 001055046 915__ $$0StatID:(DE-HGF)0700$$2StatID$$aFees$$d2025-11-11 001055046 915__ $$0StatID:(DE-HGF)0199$$2StatID$$aDBCoverage$$bClarivate Analytics Master Journal List$$d2025-11-11 001055046 920__ $$lyes 001055046 9201_ $$0I:(DE-Juel1)IBI-7-20200312$$kIBI-7$$lStrukturbiochemie$$x0 001055046 980__ $$ajournal 001055046 980__ $$aVDB 001055046 980__ $$aUNRESTRICTED 001055046 980__ $$aI:(DE-Juel1)IBI-7-20200312 001055046 9801_ $$aFullTexts