1. A substance that Reacts with free amino acids to yield CO2, NH3, and an aldehyde, the NH3 further yielding a colored product (diketohydrindylidene-diketohydrindamine, a bi-indanedione derivative also called Ruhemann purple).
The definition information for ninhydrin is provided by Stedman's. You can search our medical dictionary here.
Stedman's, part of Lippincott Williams & Wilkins, provides a comprehensive line of health-science publications for healthcare professionals and medical students.