title: Analysis of fenretinide and its metabolites in human plasma by liquid chromatography-tandem mass spectrometry and its application to clinical pharmacokinetics.
abstract: A simple and accurate high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the determination of N-(4-hydroxyphenyl)retinamide (fenretinide, 4-HPR) and its metabolites, 4-oxo-N-(4-hydroxyphenyl)retinamide (4-oxo-4-HPR) and N-(4-methoxyphenyl)retinamide (4-MPR), in human plasma. Plasma samples were prepared using protein precipitation with ethanol. Chromatographic separation of the three analytes and N-(4-ethoxyphenyl)retinamide (4-EPR), an internal standard, was achieved on a Zorbax SB-C18 column (3.5μm, 50×2.1mm) using gradient elution with the mobile phase of 0.1% formic acid in water and acetonitrile (pH* 2.4) at a flow rate of 0.5mL/min. Electrospray ionization (ESI) mass spectrometry was operated in the positive ion mode with multiple reaction monitoring (MRM). The calibration curves obtained were linear over the concentration range of 0.2-50ng/mL with a lower limit of quantification of 0.2ng/mL. The relative standard deviation of intra-day and inter-day precision was below 7.64%, and the accuracy ranged from 94.92 to 105.43%. The extraction recoveries were found to be higher than 90.39% and no matrix effect was observed. The analytes were stable for the durations of the stability studies. The validated method was successfully applied to the analyses of the pharmacokinetic study for patients treated with 4-HPR in a clinical trial.
authors.affiliation: Cancer Center, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Cell Biology and Biochemistry, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA.
authors.forename: Hwang Eui
authors.initials: HE
authors.lastname: Cho
authors.affiliation: Cancer Center, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Cell Biology and Biochemistry, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA; Pharmacology and Neuroscience, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA. Electronic address: min.kang@ttuhsc.edu.
authors.forename: H Kang
authors.initials: HK
authors.lastname: Min
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000465:Algorithms; D002853:Chromatography, Liquid; D017321:Clinical Trials, Phase I as Topic; D017313:Fenretinide / Q000097:blood* / Q000493:pharmacokinetics*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007477:Ions; D057230:Limit of Detection; D013058:Mass Spectrometry; D009447:Neuroblastoma / Q000097:blood / Q000188:drug therapy; D011786:Quality Control; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization; D013696:Temperature; D014212:Tretinoin / Q000031:analogs & derivatives / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D000097:Acetonitriles; D007477:Ions; D014867:Water; D017313:Fenretinide; D014212:Tretinoin; C058346:N-(4-methoxyphenyl)retinamide; C032159:acetonitrile
keywords: Assay development; Clinical pharmacokinetics; Fenretinide (4-HPR); LC–MS/MS