The saturated picric acid in isopropanol is a solution mainly used in histology and cytology to fix and stain tissue specimens. This solution consists of picric acid, a strong oxidant and fixative, dissolved in isopropanol, an alcohol often used as a solvent and drying agent.

Saturated picric acid in isopropanol allows effective fixation and preservation of cellular and tissue structures while preserving morphology and intracellular components. The use of isopropanol as a solvent in this solution contributes to the effective penetration of picric acid into tissue, improving the fixation and staining of tissue specimens.

In addition to its use in histology and cytology, picric acid-isopropanol solution is also important in metallography. In metallography, it is used to etch metals, especially iron-based alloys, to visualize grain structure and phase distribution. Etching with picric acid can be used to analyze microstructures of metals and alloys, which is crucial for quality control and the development of new materials.