Fixative
A chemical agent used to preserve biological specimens by cross-linking or denaturing proteins to prevent cellular degradation.
Full Definition
A fixative is the chemical solution applied during the fixation process to stabilise tissue or cytological specimens for analysis. The most widely used fixative in clinical pathology is 10% neutral buffered formalin (NBF), though alternatives such as glutaraldehyde, Bouin's solution, and alcohol-based fixatives are used for specific applications. Editors must note that 'fixative' is a noun referring to the substance, whereas 'fixation' refers to the procedure. Incorrect use of these terms in laboratory reports can create ambiguity for pathologists and laboratory accreditation reviewers.
Usage
Usage note: Distinguish clearly from 'fixation.' In document editing, verify that the fixative type and concentration are explicitly stated in protocols.
In Context
- "Specimens must be immersed in the appropriate fixative within one hour of excision to ensure optimal tissue preservation." — Surgical pathology specimen handling guide
- "The laboratory transitioned from Bouin's fixative to 10% NBF to standardise processing across all tissue types." — Laboratory policy document