An integrated ELF magnetic-field generator and incubator for long-term in vitro studies

Long-term studies of the effects of low-frequency magnetic fields on cells in culture require an incubator that is free of contaminating magnetic fields and that provides automatic control of exposure duration, uniform applied fields, a uniform and well-controlled environmental temperature, and high reliability of the total system. We describe a dual-incubator system in which the enclosed solenoid of either unit can provide a sham exposure while the other generates a magnetic induction of up to 500 microT. Each solenoid-incubator unit contains an enclosed rack that can hold as many as 140 petri dishes for culturing cells; each unit is heated radiantly by circulating warm water. Field-exposure conditions and temperatures are continuously monitored and controlled by a microcomputer.