Preservation of structure and cytochemical reactivity at the ultrastructural level, using microwave irradiation.

The application of microwave irradiation at various steps in 'normal' EM procedures has been investigated. 1. The temperatures in various aqueous volumes were measured during microwave irradiation. Increases were small and the final temperature could be controlled by cooling the glass base plate. 2. The influence of microwave irradiation on the various fixation schedules for the electron microscopy of single cell populations was studied and the results favoured the idea that by the application of microwave irradiation a more life-like ultrastructural preservation could be obtained. 3. Peroxidase-like activity in erythrocytes, acid phosphatase activity in resident macrophages and peroxidase activity in monocyte granules was apparently not influenced by microwave irradiation during aldehyde fixation and incubation. 4. The anticipated microwave-induced penetration enhancement of cerium ions in a cytochemical reaction procedure to detect acid phosphatase activity in resident macrophages was not observed.