IN-VITRO AND IN-VIVO EVALUATION OF POTENTIAL ALUMINUM CHELATORS

The potential for aluminium (Al) chelation by different compounds was determined using 2 in vitro techniques. The formation of stable comple xes with Al in an aqueous solution was evaluated using pulse polarogra phy. This technique allowed the influence of temperature and calcium ( Ca) to be studied for each compound. Certain compounds (EDDHA, HAES, c itric acid and HEED) showed great chelation in the absence of Ca2+ at a temperature of 37 +/- 1 C. An ultrafiltration technique combined wit h Al determination by atomic emission spectroscopy allowed the efficie ncy of different substances to complex Al that were previously bound t o serum proteins to be estimated. The kinetics of chelation and minimu m efficient concentration have been determined for all products studie d. EDDHA had chelation potential similar to DFO. The real efficacies o f the compounds were studied in vivo to compare the effectiveness of r epeated administrations of the best chelating agents (EDDHA, DFO, HAES and tartaric acid) on the distribution and excretion of Al after repe ated ip administrations to rats. Intraperitoneal EDDHA significantly i ncreased urinary metal (Al, Ca, Cu, Fe and Zn) excretion. These excret ions may be correlated to a renal toxic potential property.