Abstract

Recently, specimen processing using microwave irradiation was described as a potential tool to enhance a variety of procedures used in microscopy including fixations, embedding, antigen retrieval (AGR) and immunolabeling (1,2,3). A comparison of conventional staining and staining after microwave irradiation was performed for several fluorescent vital nuclear stains, Performing the labeling reaction under controlled microwave irradiation results in significant improvements in the labeling of nuclei, such as shortening the times of incubation and allowing the detection of otherwise inaccessible sites. In addition to investigate the basis of the enhancement, we have labeled intact samples such as living onion root meristems and Drosophila embryos. In both systems, vital fluorescent nuclear stains were applied to the specimen on a glass slide and was microwave irradiated using a variable wattage microwave (model 3451 Ted Pella, Inc.). This resulted in clear fluorescent labeling of the nuclei. This result has not been previously reported in the absence of microwave treatment, other than by microinjection.