Name one common fixative used in histopathology.

Formalin is a widely used fixative in histopathology primarily due to its ability to preserve tissue morphology while also providing excellent penetration and fixation of cellular structures. It is a solution of formaldehyde in water, typically buffered to maintain a neutral pH. This fixative effectively cross-links proteins, which helps to stabilize the tissue components and prevent degradation during processing and embedding. Additionally, formalin is compatible with routine staining protocols, making it a preferred choice among histotechnologists.

While other options like alcohol and acetone can be used as fixatives in specific circumstances, such as for certain cytological specimens or in situations requiring rapid fixation, they are not as commonly employed as formalin for general histopathology due to their adverse effects on tissue morphology and greater risk of artifacts. Phenol has its applications but is less frequently utilized as a primary fixative in typical histological practices. Therefore, formalin stands out as the standard choice for tissue fixation in histopathology.