THE USE OF MICROWAVE ACCELERATED CHEMICAL FIXATION FOR

Objectives: The aim of the present study was to evaluate the effectiveness ofusifzgmicrowaves alone or microwave-assisted chemical fixation and comparing them with the conventional method of chemical fixation for electron microscopy. Methods: A domestic microwave oven was used in this study. Total exposure time to microwave irradiation was 10 seconds. Liver specimens from 5 albino rats were taken. Specimens were divided into 5 groups. The first group represented the conventional chemical fixation without the use of microwaves, while fixation in the remaining 4 groups was done using microwave irradiation alone or assisting different chemicalfixatives. Results: The mere use of microwave irradiation for fixation gave disappointing results and caused severe tissue damage. The microwave-glutaraldehyde fixation resulted in good degree of preservation of most of intracytoplasmic constituents exceptfor ill defined membranes. The use of microwave-osmium fixation gave a very good preservation of liver ultrastructure but with the disadvantage of faint stained chromatin. The excellent preservation of liver tissue with well demarcated ultrastructural morphological details equivalent to the chemical conventional method was obtained by the sequential use of microwave-glutaraldehyde fixation followed by microwaveosmium post-jlXation. Conclusion: The microwave irradiation assisted and accelerated the chemicaljUation. it reduced the processing time significantly with resultant excellent degree of preservation of tissue structure. However, the use of microwaves cannot be a tool to eliminate the use of chemical fixation which proved to be essential in electron microscopic preparations