Molar absorption coefficients and stability constants of metal complexes of 4-(2-pyridylazo)resorcinol (PAR): Revisiting common chelating probe for the study of metalloproteins

Re-determined values of effective molar absorption coefficients (εeff) of 4-(2-pirydylazoresorcinol) (PAR) complex with Zn2 +, Cd2 +, Hg2 +, Co2 +, Ni2 +, Cu2 +, Mn2 + and Pb2 + and effective dissociation constants (Kdeff) with Zn2 + allow for precise calculation of metal ion concentrations and affinities of metalloproteins.