title: [Study on the enhancement diphacinone-europium fluorescence system and application for determination of the residue in urine].
abstract: OBJECTIVE
  To establish an accurate, convenient and sensitive quantitative fluorescence method for the determination of diphacinone (DPN) in urine.
  
  
  METHODS
  Diphacinone was complexed with europium ion (Eu3+) at the presence of DL-histidine, polyvinylpyrrolidone (PVP) and ammonia-ammonium chloride (NH3 -NH4 Cl) buffer solution to form a multiple complex of DPN-Eu(3+) -DL-histidine-NH3-PVP fluorescence system, and the fluorescence sensitivity was greatly enhanced by the rare earth element of yttrium ion (Y3+ ). The excitation and emission wavelengths were 330 nm and 612 nm, respectively.
  
  
  RESULTS
  The optimum conditions were Eu3+ 10.0 mg/L,Y3+ 20.0 mg/L, DL-histidine 0.01%, PVP 0.05% at pH 9.0. Under the optimum conditions, fluorescence intensity of the system was a linear function of the concentration of diphacinone in the range of 0.2 - 10.0 mg/L, the limit of quantification was 0.2 mg/L. The spiked recoveries for DPN in urine were 87.0% - 97.3%, the intra-and inter-day RSDs were between 3.4% - 4.7% and 4.8% - 6.6%, respectively.
  
  
  CONCLUSIONS
  The established method is simple, accurate and reliable, and it is satisfactory for the determination of DPN in urine and can be used for DPN poisoned patients for the rapid clinical diagnosis.
authors.affiliation: Ningbo Key Laboratory of Poison Research and Control, Ningbo Municipal Center for Disease Control and Prevention, Ningbo 315010, China. chenxh@nbcdc.org.cn
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Chen
authors.forename: Meiqiang
authors.initials: M
authors.lastname: Cai
authors.forename: Micong
authors.initials: M
authors.lastname: Jin
mesh_terms: D005456:Fluorescent Dyes / Q000737:chemistry*; D010630:Phenindione / Q000031:analogs & derivatives* / Q000652:urine; D012378:Rodenticides / Q000652:urine*; D013050:Spectrometry, Fluorescence
chemical_list: D005456:Fluorescent Dyes; D012378:Rodenticides; C100262:diphenadione; D010630:Phenindione