title: An enhancement of europium-/gadolinium- diphacinone -DL-histidine- cetylpyridine bromide system for the determination of diphacinone in serum.
abstract: As one of the first generation anticoagulant rodenticide, diphacinone (DPN) was extensively used in China, and often occurred accidental and intentional intoxications. To meet the needs of clinical emergency rescue, a simple, rapid and sensitive method was necessary for the determination of DPN in serum. In this paper, a fluorimetric method using a ternary europium-gadolinium-DPN-DL-histidine-cetylpyridine bromide system was developed. The fluorescence intensity was measured with a 1 cm quartz cell at 335 nm excitation wavelength and 612 nm emission wavelength. The fluorescence intensity of the europium-DPN- DL- histidine complex system was further enhanced by using gadolinium ion (Gd(3+)) in a cetylpyridine bromide (CPB) colloid-type suspension. By adding Gd(3+) at pH 8.5 to 9.5 in the presence of an ammonia-ammonium chloride buffer solution, about a 100-fold enhancement of the fluorescence intensity was achieved. The enhanced fluorescence intensity showed a good linear relationship with the DPN concentration from 0.01 mg/L to 5.0 mg/L. The limit of detection was 0.001 mg/L in serum. The established method was used to determine DPN in real human serum in clinical specimens. The luminescence mechanism was discussed in detail. In the fluorescence system of the europium-gadolinium-DPN-DL-histidine-CPB, the CPB not only acted as the surfactant but also acted as the energy donor.
authors.affiliation: College of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310035, People's Republic of China.
authors.forename: Meiqiang
authors.initials: M
authors.lastname: Cai
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Chen
authors.forename: Micong
authors.initials: M
authors.lastname: Jin
mesh_terms: D000328:Adult; D001965:Bromides / Q000737:chemistry; D002594:Cetylpyridinium / Q000737:chemistry; D002648:Child; D005063:Europium / Q000737:chemistry; D005260:Female; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D005682:Gadolinium / Q000737:chemistry; D006639:Histidine / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010630:Phenindione / Q000031:analogs & derivatives* / Q000097:blood / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D055815:Young Adult
chemical_list: D001965:Bromides; D005456:Fluorescent Dyes; D009942:Organometallic Compounds; D005063:Europium; D006639:Histidine; C100262:diphenadione; D010630:Phenindione; D005682:Gadolinium; D002594:Cetylpyridinium