Detailed Protocol for Expansion of Large Tissue Samples for Expansion Microscopy.

Expansion microscopy (ExM) is a powerful technique that enhances optical resolution by physically enlarging biological samples. The enlargement increases the distances between fluorophores and makes the sample transparent. Here, we present an ExM protocol optimized for tissue biopsies with 2 mm diameter and 1 mm thickness from inner medulla from perfusion-fixed rat kidneys. Besides inner medulla kidney samples, the protocol may be utilized for other tissue types with minor modifications.