Supplier Page from Thermo Fisher Scientific for Diphenylamine-4-sulfonic acid, sodium salt, ACS reagent
4-Ethylresorcinol, 98% from Thermo Fisher Scientific
4-Fluoroaniline, 98% from Thermo Fisher Scientific
Ethyl indole-2-carboxylate, 97% from Thermo Fisher Scientific
Fluorescein, pure from Thermo Fisher Scientific