What preservative is most commonly used for tissue specimens before laboratory analysis?

The most commonly used preservative for tissue specimens before laboratory analysis is a 10% formalin solution. Formalin, which is a solution of formaldehyde in water, effectively preserves biological tissues by preventing decay and autolysis. It cross-links proteins and nucleic acids, thus stabilizing the cellular structure and allowing for clear visualization of tissue morphology during histological examination.

The use of 10% formalin is widespread in pathology departments due to its effectiveness in maintaining tissue integrity while allowing for subsequent staining and microscopic evaluation. This preservation is critical for accurate diagnosis and research, as it preserves the cellular architecture and prevents degradation of tissue components.

In contrast, while 70% ethanol can be used for certain tissue types and specific applications, it is not the standard for preserving tissues intended for histopathological examination. Saline solution, which is primarily isotonic and not preservative in nature, is typically used for transporting tissues rather than preserving them. Lastly, acetic acid is more commonly used in cytology and for certain types of fixation rather than as a standard tissue preservative. Each of these alternatives has its specific uses, but none compare to the widespread application of 10% formalin in preserving tissue specimens for laboratory analysis.