title: Lysozyme-enhanced europium(III)-metacycline luminescence and its application to the determination of metacycline.
abstract: A new spectrofluorometric method is described for the determination of metacycline (MC), based on modified enzyme-amplified lanthanide luminescence. Under the optimum conditions, Eu3+-MC forms a ternary complex with lysozyme in close proximity. Then lysozyme can remarkably enhance the characteristic fluorescence intensity of Eu3+ at 612 nm in metacycline-Eu3+ binary complex. The enhanced fluorescence intensity is in proportion to the concentration of MC. The limit of detection is 1.6 x 10(-8) mol L(-1), with a linear range from 6.2 x 10(-6) to 1.7 x 10(-5) mol L(-1). Interferences of other coexisting substances were studied. The developed method was successfully applied to the determination of MC in serum and urine samples. The mechanism of fluorescence enhancement was also studied.
authors.affiliation: Department of Chemistry, Shandong Normal University, Jinan, 250014, China.
authors.forename: Na
authors.initials: N
authors.lastname: Zhang
authors.forename: Jin-Kai
authors.initials: JK
authors.lastname: Liu
authors.forename: Chong-Qiu
authors.initials: CQ
authors.lastname: Jiang
mesh_terms: D005063:Europium / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D049449:Luminescence; D008690:Methacycline / Q000737:chemistry*; D009113:Muramidase / Q000737:chemistry*; D010084:Oxidation-Reduction; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature
chemical_list: D007202:Indicators and Reagents; D005063:Europium; D009113:Muramidase; D008690:Methacycline