Low density lipoprotein quantification and Arcus Corneus and atheroma optical imaging using probe/marker europium chrortetracycline complex (animal model)

• Grant number: 10/16544-1
• Support Opportunities: Regular Research Grants
• Start date: April 01, 2011
• End date: March 31, 2013
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Lilia Coronato Courrol
• Grantee: Lilia Coronato Courrol
• Host Institution: Pró-Reitoria de Pós-Graduação e Pesquisa. Universidade Federal de São Paulo (UNIFESP). São Paulo , SP, Brazil
• Associated researchers: Andrea Moreira Monteiro ; Antonio Martins Figueiredo Neto

Abstract

The Europium-Chlortetracycline complex (EuCTc) presents interesting optical properties, such as absorption around 400 nm and a large Stokes shift that originates an emission around 615 nm with a fluorescent lifetime of a few microseconds, which differs from the lifetimes of biological tissues. With the addition of small amounts of low density lipoproteins (LDL) there is a five-fold increase in the Europium emission intensity at 615 nm in solutions with neutral pH. The europium complex EuCTc-LDL emission lifetime increases to 50 microseconds due to a reduction in the luminescence quenching by energy transfer. Studies have shown that the incorporation of inorganic ions in the Europium Clorotetracycline complex solution allows differentiation of the LDL oxidation state. Such characteristics provide high sensitivity and specificity in the detection of modified LDL. The EuCTc complex is easily synthesized, operates at neutral pH, has high stability and low cost.Our main challenge is to test if the method of LDL quantification, using the probe europium Chlortetracycline, is valid in whole blood, which enables a simple and rapid quantification of native or modified LDL. For this purpose, the fluorescence analysis of blood samples from rabbits subjected to high-cholesterol diets will be performed along with analyses of the arteries and corneas of these animals by fluorescence microscopy and by using the complex EuCTc as fluorescent marker, following the development of the framework of hypercholesterolemia. (AU)