The staining properties of thiazolylazoalkylaminophenol derivatives in histochemical staining of cadmium.

In the continuous research for a more sensitive chelator for cadmium, thiazolylazoalkylaminophenol derivatives were synthesized. The staining sensitivity for cadmium and molar absorptivity of their cadmium chelates were examined. Though the molar absorptivity of bromothiazolylazodiethylaminophenol(Br-TADA)-cadmium chelate demonstrated an order of 10(5), the staining sensitivity of Br-TADA was unexpectedly low. The lowering of the sensitivity of Br-TADA may be attributed to alkaline hydrolysis and a decrease in the stability constant of the cadmium chelate.