Novel fluorescent probe for low density lipoprotein, based on the enhancement of Europium emission band

We report here the observation of the enhancement of Europium-tetracycline complex emission in Low Density Lipoprotein (LDL) solutions. Europium emission band of tetracycline solution containing Europium (III) chloride hexahydrate was tested to obtain effective enhancement in the presence of native LDL and oxidized LDL. Europium emission lifetime in the presence of lipoproteins was measured, resulting in a simple method to measure the lipoproteins quantity in an aqueous solution at physiological pH. This method shows that the complex can be used as a sensor to determine the different states of native and oxidized LDL in biological fluids. (C) 2007 Optical Society of America.Universidade Federal de São Paulo, Eldorado Diadema, SP, BrazilUniv São Paulo, Escola Politecn, LSI, São Paulo, BrazilUniv São Paulo, Inst Ciencias Biol, São Paulo, BrazilUniv São Paulo, Inst Fis, BR-05315970 São Paulo, BrazilUniversidade Federal de São Paulo, Eldorado Diadema, SP, BrazilWeb of Scienc