Applications
Phthaldialdehyde is used as a fluorescent reagent for checking the assay of amines present in proteins, peptides by capillary electrophoresis and chromatography. It is also used for cholesterol assay in the picomole range as well as for fluorometric determination of histamine, histidine and other amino acids. Poly(phthalaldehyde) is obtained by the polymerization reaction which is used to make a photoresist. The nitrogen by o-phthaldialdehyde assay (NOPA) is a method used in winemaking process to measure the completion of fermentation.

Solubility
Soluble in acetic acid and methanol. Slightly soluble in water.

Notes
Air, light and moisture sensitive. Store in cool place. Keep the container tightly closed in a dry and well-ventilated place. Incompatible with oxidizing agents, amines and strong bases.