title: Simultaneous determination of l-citrulline and l-arginine in plasma by high performance liquid chromatography.
abstract: OBJECTIVE
  To develop a method for simultaneously determining l-citrulline and L-arginine levels in plasma using RP-HPLC with ultraviolet detection.
  
  
  METHODS
  Plasma samples were deproteinized by trichloroacetic acid and heat. Phenyl-isothiocyanate (PITC) solution was used as derivatization reagent and a gradient elution was carried out.
  
  
  RESULTS
  The linearity for L-citrulline and L-arginine ranged from 0 to at least 1000 micromol/L. R(2) values were above 0.9999 for both. LODs for L-citrulline and L-arginine were 0.0201 micromol/L and 0.0476 micromol/L, respectively, while LOQs were 0.240 micromol/L and 0.448 micromol/L, respectively. Intra- and inter-day CVs were less than 3.40% and 7.2%, respectively. The average recovery was from 86.22% to 118.9%. L-citrulline and L-arginine concentrations in healthy controls were 60.77+/-9.18 micromol/L and 58.19+/-16.43 micromol/L, respectively.
  
  
  CONCLUSIONS
  This approach offers a reliable, efficient analytical platform for the simultaneous determination of citrulline and arginine levels in plasma.
authors.affiliation: Department of Central Laboratory, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China.
authors.forename: Hui-ming
authors.initials: HM
authors.lastname: Mao
authors.forename: Wei
authors.initials: W
authors.lastname: Wei
authors.forename: Wu-jun
authors.initials: WJ
authors.lastname: Xiong
authors.forename: Ying
authors.initials: Y
authors.lastname: Lu
authors.forename: Bing-guan
authors.initials: BG
authors.lastname: Chen
authors.forename: Zhongmin
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001120:Arginine / Q000097:blood*; D016022:Case-Control Studies; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000592:standards; D002956:Citrulline / Q000097:blood*; D005260:Female; D006801:Humans; D007202:Indicators and Reagents; D057230:Limit of Detection; D008297:Male; D008722:Methods; D008875:Middle Aged; D009369:Neoplasms / Q000097:blood
chemical_list: D007202:Indicators and Reagents; D002956:Citrulline; D001120:Arginine