title: [Determination of phenylalanine and tyrosine in serum by high-performance liquid chromatography with fluorescent detection].
abstract: OBJECTIVE
  To determine phenylalanine and tyrosine in serum by high-performance liquid chromatography (HPLC) method.
  
  
  METHODS
  Serum precipitated with perchloric acid was isocratically eluted using a base-deactivated C8 column with 10% acetonitrile in water as the mobile phase. The flow rate was 1.0 ml/min. Fluorescent detector worked at an excitation wavelength of 210 nm and emission wavelength of 303 nm.
  
  
  RESULTS
  Good linearity was observed in the range of 12.2 approximately 1 220.0 micromol/L for phenylalanine, the intra- and inter-assay coefficients of variation (CV) were 4.07% and 7.17% respectively, and the average recovery was 102.5%. There also was a good linearity in the range of 5.5 approximately 550.0 micromoL/L for tyrosine. The intra- and inter-assay coefficients of variation were 2.99% and 5.23% respectively, and the average recovery was 102.2%. The total assay time for the serum sample was within 30 min. We found a good correlation compared with HPLC ultraviolet detection.
  
  
  CONCLUSIONS
  This method is simple, rapid, accurate in measuring phenylalanine and tyrosine in serum quantitatively.
authors.affiliation: Department of Clinical Laboratory, Second Xiangya Hospital, Central South University, Changsha 410011, China.
authors.forename: Min
authors.initials: M
authors.lastname: Hong
authors.forename: Ai-Guo
authors.initials: AG
authors.lastname: Tang
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005453:Fluorescence; D006801:Humans; D007223:Infant; D008297:Male; D010649:Phenylalanine / Q000097:blood*; D014443:Tyrosine / Q000097:blood*
chemical_list: D014443:Tyrosine; D010649:Phenylalanine