Aluminum polymeric implants: in vitro-in vivo evaluations

The purpose of this investigation is to study the effect of long-term subcutaneous aluminum polymeric implants on aluminum release and accumulation in various tissues in rats. The implants were formulated using silicone rubber and polyurethane polymers and three different aluminum salts. The polymeric matrices were evaluated for in vitro release studies. These matrices released aluminum in vitro up to the period of four months. The aluminum matrices were implanted in rats and animals were sacrificed at various time intervals. Various tissues such as brain, kidney, liver, intestine, and heart were isolated. Aluminum in dried tissues was analyzed by Neutron Activation Analysis. Results from this investigation suggest that polymeric aluminum implants raise the aluminum concentration in the brain and liver. However, these implants did not increase aluminum levels in intestine, heart, and kidney. The polymeric aluminum implants could be used to establish an animal model for the neuropathology of dementia.