{"doi":"10.1002/dta.3006","title":"Determination of vitamin E and its metabolites in equine urine using liquid chromatography–mass spectrometry","abstract":"Equine neuroaxonal dystrophy/degenerative myeloencephalopathy (eNAD/EDM) is a hereditary, deteriorating central nervous disease in horses. Currently, the only way to confirm eNAD/EDM is through a postmortem histological evaluation of the central nervous system. Vitamin E, specifically the isoform alpha-tocopherol (α-TP), is known to protect eNAD/EDM susceptible horses from developing the clinical phenotype. While vitamin E is an essential nutrient in the diet of horses, there are no diagnostic tests able to quantitate vitamin E and its metabolites in urine. An ultra-performance liquid chromatography-atmospheric-pressure chemical ionization mass spectrometry (UPLC-APCI-MS/MS) method was developed and validated following acidic hydrolysis and solid phase extraction to quantitate vitamin E and its metabolites in equine urine. A blank control horse urine matrix was used and spiked with different concentrations of analytes to form a standard curve using either alpha-tocopherol-d6 or chlorpropamide as the internal standard. Inter-day and intra-day statistics were performed to evaluate the method for accuracy (90% to 116%) and precision (0.75% to 14%). Matrix effects, percent recovery, and stability were also assessed. The method successfully analyzed alpha-carboxyethyl hydroxychroman (α-CEHC), alpha-carboxymethylbutyl hydroxychromans (α-CMBHC), gamma-carboxyethyl hydroxychroman γ-CEHC, and α-TP concentrations in urine to determine a baseline levels of analytes in healthy horses, and can be used to determine concentrations of vitamin E metabolites in equine urine allowing for its evaluation as a diagnostic approach in the treatment of eNAD/EDM.","journal":"Drug Testing and Analysis","year":2021,"id":206501,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":5,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9594,"is_data_producer":false,"deposit_databanks":null,"is_oa":false,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":756704,"name":"Hadi Habib","orcid":null,"position":1,"is_corresponding":false},{"id":790285,"name":"Ingrid Gennity","orcid":null,"position":2,"is_corresponding":false},{"id":732883,"name":"Birgit Puschner","orcid":"0000-0001-6765-5085","position":3,"is_corresponding":false},{"id":426998,"name":"Erin N. Hales","orcid":"0000-0002-8007-6552","position":4,"is_corresponding":false},{"id":381726,"name":"Carrie J. Finno","orcid":"0000-0001-5924-0234","position":5,"is_corresponding":false},{"id":528952,"name":"Benjamin C. Moeller","orcid":"0000-0003-2945-3620","position":6,"is_corresponding":false},{"id":756705,"name":"Gianna Favro","orcid":null,"position":0,"is_corresponding":true}],"reference_count":40,"raw_metadata":null,"created_at":"2026-07-18T23:51:41.571653Z","pmid":"33527764","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}