title: Measurement of 3-hydroxyisovaleric acid in urine of biotin-deficient infants and mice by HPLC.
abstract: We developed an assay for measuring urinary 3-hydroxyisovaleric acid (3-HIA) using HPLC after derivatization with 2-nitrophenylhydrazine hydrochloride (2-NPH . HCl). The derivatized 3-HIA was extracted into n-hexane and separated isocratically on a C8 reversed-phase column for fatty acids (YMC-Pack FA). We used this method to measure 3-HIA in urine extracts from mice fed a biotin-deficient diet for >4 wk and in an infant who was fed a special Japanese formula and was suspected of being biotin deficient. Urinary 3-HIA could be assayed within the range of 0.42-8.5 mmol/L with high accuracy by this method, as an indicator of biotin deficiency. Therefore, the HPLC method for 3-HIA described here may be a useful tool clinically as well as in the research laboratory.
authors.affiliation: School of Human Science and Environment, Himeji Institute of Technology, University of Hyogo, Himeji 670-0092, Japan. watanabe@shse.u-hyogo.ac.jp
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Watanabe
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Oguchi
authors.forename: Shuhei
authors.initials: S
authors.lastname: Ebara
authors.forename: Toru
authors.initials: T
authors.lastname: Fukui
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood; D001710:Biotin / Q000172:deficiency* / Q000652:urine*; D002851:Chromatography, High Pressure Liquid; D003677:Deficiency Diseases / Q000652:urine; D006801:Humans; D007223:Infant; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D012044:Regression Analysis; D014631:Valerates / Q000652:urine*
chemical_list: D015415:Biomarkers; D014631:Valerates; C004961:beta-hydroxyisovaleric acid; D001710:Biotin