New Trinder's Reagents are stable enough to use in both solution and test strip detection systems. They form highly stable purple or blue dyes through an oxidative coupling reaction with 4-Aminoantipyrine(4-AA) in the presence of hydrogen peroxide and peroxidase. The table below shows the maximum wavelength and molar absorptivity of each oxidized New Trinder's Reagent complex with 4-AA.

Tetrazolium Salts are unique compounds with a slightly yellow color that generate intense orange to purple formazan dyes when reduced. This chemical property makes it possible to apply tetrazolium salts into a wide range of applications, for example, metabolism enzymatic assays, staining, cell viability monitoring and immunoassays in conjunction with an electron mediator. Below are the optical properties of formazan dyes of each tetrazolium salt.