title: Determination of coenzyme Q10 in human breast milk by high-performance liquid chromatography.
abstract: An isocratic HPLC method was developed for the determination of coenzyme Q(10) (CoQ(10)) in human breast milk. After a single-step liquid-liquid extraction, the milk extract was injected directly into the HPLC system. The analytical method is based on pre-column inline treatment of CoQ(10). Chromatographic separation of CoQ(10) and coenzyme Q(9) (CoQ(9)) internal standard was achieved using a reversed-phase Microsorb-MV C(18) analytical column. CoQ(10) and CoQ(9) were monitored by an electrochemical detector (ECD). An excellent linearity (r = 0.999) was observed for CoQ(10) in the concentration range 0.06-2.5 micromol L(-1) in breast milk. The limit of quantitation (LOQ) was 60 nmol L(-1). Coefficients of variations (CVs) for intra-day and inter-day assay precisions were less than 5%. A total of 194 breast milk samples were analyzed for the CoQ(10) concentration; the mean value was 0.32 +/- 0.21 micromol L(-1).
authors.affiliation: Division of Pathology and Laboratory Medicine, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH 45229-3039, USA. peter.tang@cchmc.org
authors.forename: Peter H
authors.initials: PH
authors.lastname: Tang
authors.forename: Michael V
authors.initials: MV
authors.lastname: Miles
authors.forename: Paul
authors.initials: P
authors.lastname: Steele
authors.forename: Barbara S
authors.initials: BS
authors.lastname: Davidson
authors.forename: Sheela R
authors.initials: SR
authors.lastname: Geraghty
authors.forename: Ardythe L
authors.initials: AL
authors.lastname: Morrow
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003067:Coenzymes; D004355:Drug Stability; D005260:Female; D006801:Humans; D008895:Milk, Human / Q000737:chemistry*; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000032:analysis
chemical_list: D003067:Coenzymes; D014451:Ubiquinone; C024989:coenzyme Q10