title: Sensitive determination of DNA based on the interaction between prulifloxacin-terbium(III) complex and DNA.
abstract: A simple spectrofluorimetric method is described for the determination of DNA, based on its enhancement of the fluorescence intensity of prulifloxacin (PUFX)-Tb(3+). The luminescence intensity of the PUFX-Tb(3+) complex increased up to 10-fold after adding DNA. The excitation and emission wavelengths were 345 and 545 nm, respectively. Under optimum conditions, variations in the fluorescence intensity showed a good linear relationship with the concentration of hsDNA in the range of 3.0 × 10(-9) to 1.0 × 10(-6) g/mL, with a correlation coefficient (R) of 0.997, and the detection limit was 2.1 × 10(-9) g/mL. The method was successfully applied to the determination of DNA in synthetic samples, and recoveries were in the range 97.3-102.0%. The mechanism of fluorescence enhancement of the PUFX-Tb(3+) complex by DNA is also discussed. The mechanism may involve formation of a ternary complex mainly by intercalation binding together with weak electrostatic interaction, which will increase the energy transition from ligand to Tb(3+), increasing the rigidity of the complex, and decreasing the radiationless energy loss through O-H vibration of the H2O molecule in the PUFX-Tb(3+) complex. Compared with the previous DNA probes, the proposed method is not only more robust and friendly to the environment, but also of relatively higher sensitivity.
authors.affiliation: School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Wu
authors.forename: Biyun
authors.initials: B
authors.lastname: Fang
authors.forename: Lin
authors.initials: L
authors.lastname: Chang
authors.forename: Min
authors.initials: M
authors.lastname: Liu
authors.forename: Fang
authors.initials: F
authors.lastname: Chen
mesh_terms: D004247:DNA / Q000032:analysis* / Q000737:chemistry*; D004148:Dioxolanes / Q000737:chemistry*; D024841:Fluoroquinolones / Q000737:chemistry*; D049449:Luminescence; D008163:Luminescent Measurements; D009942:Organometallic Compounds / Q000737:chemistry*; D010879:Piperazines / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013725:Terbium / Q000737:chemistry*
chemical_list: D004148:Dioxolanes; D024841:Fluoroquinolones; D009942:Organometallic Compounds; D010879:Piperazines; D013725:Terbium; D004247:DNA; C074191:prulifloxacin
keywords: DNA; luminescence mechanism; prulifloxacin; spectrofluorimetry; terbium