Which technique is commonly used for preserving specimens for laboratory analysis?

The technique of fixation is a vital process used in laboratory analysis for preserving tissues and cells in a state that allows for accurate examination under a microscope. This method stabilizes the cellular structure, preventing degradation, and helps to maintain the morphology of the specimen, ensuring that it remains representative of the original sample. Fixatives, which are chemicals used in this process, generally work by cross-linking proteins, thereby preserving the spatial relationships within cells and tissues.

In histology, for instance, formaldehyde is one of the most common fixatives. It penetrates the tissue and causes proteins to coagulate, which helps to preserve the details of the cellular structure. This is crucial for subsequent staining procedures that allow for the visualization of specific cell types or structures, contributing to the accurate diagnosis and research findings.

Other techniques like freezing, heating, and drying do not achieve the same level of preservation for cellular architecture. Freezing may cause ice crystal formation that can disrupt cellular integrity, heating can denature proteins and alter tissue structure, and drying can lead to desiccation and loss of important morphological details. Thus, fixation stands out as the preferred technique in laboratory settings for long-term specimen preservation and analysis.