For over a hundred years, pathologists have been using conventional optical microscopes to examine biopsy samples for research and diagnosis. However, in disease states, such as cancer at early stages, tissues and cells often undergo subtle changes down to the nanoscale, which is beyond the best optical resolution of the conventional optical microscope. Therefore, pathologists rely on limited information extracted from the biopsy samples for diagnosis. This causes misdiagnosis that risks patients' life and costs time and money. To circumvent the resolution limitation of the optical microscope, we developed a technology, called Expansion Pathology, that embeds the clinical biopsy sample into an inexpensive swellable gel found in baby diapers,
