Which enzyme is commonly used for tissue fixation in histology?

Glutaraldehyde is a commonly used tissue fixation agent in histology, primarily because of its ability to preserve cellular morphology and structure. It functions as a cross-linking agent, creating covalent bonds between amino acids in proteins, which stabilizes the tissue architecture. This is particularly important for electron microscopy since it helps maintain fine structural details at the ultrastructural level.

Formalin, although widely used for tissue fixation, primarily consists of formaldehyde and is not classified as an enzyme. Its fixation capacity is largely due to the chemical reactions formaldehyde undergoes with proteins. Ethyl alcohol is more commonly used for dehydrating tissues rather than fixation. Acetone, while a potent fixative for certain applications, is also primarily used for dehydrating and can lead to protein denaturation, which is not as favorable for preserving tissue structures. Therefore, glutaraldehyde stands out for its effective fixation characteristics in histological applications, particularly when detailed tissue preservation is critical.