Amino acid Derivative Reactivity Assay ADRA is an alternative method of skin sensitization test to animal testing ADRA significantly reduces the number of chemical substances used as a reaction reagent by using a novel amino acid derivative having a naphthalene ring capable of high sensitivity detection by ultraviolet rays Also skin sensitization tests are possible even at about 1/100 by conventional methods It is possible to evaluate skin sensitization with high accuracy without causing chemical substances to precipitate in the reaction solution It evaluates whether a chemical substance provokes an allergic reaction in the skin without using animal models Reagent kit for performing ADRA as described in OECD TG 442C