title: Determination of clofarabine triphosphate concentrations in leukemia cells using sensitive, isocratic high-performance liquid chromatography.
abstract: OBJECTIVE
  An active metabolite of the anti-leukemia agent clofarabine (Cl-F-ara-A) is an intracellular triphosphate form, Cl-F-ara-ATP. Monitoring this active form could provide crucial information for optimizing treatment regimens based on Cl-F-ara-A. A simple, isocratic HPLC method was developed.
  
  
  METHODS
  Samples (500 μl) from leukemic cells were loaded onto an anion-exchange column and eluted with a phosphate-acetonitrile buffer (flow rate: 0.7 ml/min) at ambient temperature. The Cl-F-ara-ATP concentration was determined by measuring absorbance at 254 nm.
  
  
  RESULTS
  The standard curve was linear, with minimal within-day and inter-day variability. Recovery was excellent; low and high quantitation limits were 10 pmol and 5,000 pmol, respectively. Cl-F-ara-ATP eluted independently of ATP, GTP, UTP, and CTP. Production of Cl-F-ara-ATP was successfully measured in cultured leukemia HL-60 cells treated in vitro with Cl-F-ara-A.
  
  
  CONCLUSIONS
  This method is simple, sensitive and applicable for determination of the Cl-F-ara-ATP content of biological materials.
authors.affiliation: Department of Hematology and Oncology, University of Fukui, 23 Shimoaizuki, Matsuoka, Eiheiji, Fukui 910-1193, Japan. tyamauch@u-fukui.ac.jp
authors.forename: Takahiro
authors.initials: T
authors.lastname: Yamauchi
authors.forename: Rie
authors.initials: R
authors.lastname: Nishi
authors.forename: Takanori
authors.initials: T
authors.lastname: Ueda
mesh_terms: D000227:Adenine Nucleotides / Q000032:analysis*; D000970:Antineoplastic Agents / Q000032:analysis*; D001087:Arabinonucleosides / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D000077866:Clofarabine; D018922:HL-60 Cells; D006801:Humans; D007938:Leukemia / Q000473:pathology*; D015203:Reproducibility of Results
chemical_list: D000227:Adenine Nucleotides; D000970:Antineoplastic Agents; D001087:Arabinonucleosides; D000077866:Clofarabine