PHYSICAL STABILIZATION AND EMBEDDING OF MICROBIAL AGGREGATES FOR LIGHT-MICROSCOPY STUDIES

An improved technique for the physical stabilization of microbial aggregates, by embedding them in solidified agar, is recommended for light microscopy studies such as the measurement of size and the evaluation of morphological parameters. This technique involves an application of membrane filtered agar and allows the use of an image analysis system for observations of aggregates down to the size of individual cells. Embedding in agar is not satisfactory for microtome sectioning of microbial aggregates. Instead of the previously studied method of embedding in paraffin, embedding in glycol methacrylate resin has been found more advantageous. The latter technique is much simpler and provides better, unperturbed specimens.