Histotechnology I- Miscellaneous
Question No. 15. The Answer is: (C) Diaminobenzidine.
Discussion: Both diaminobenzidine (DAB) and 3-amino-9-ethylcarbazole. (AEC) are substrates for peroxidases. While DAB gives a brown product, AEC gives a red product. Fast red TR, nitro blue tetrazolium, and hexazotized new fuchsin are substrates for alkaline phosphatase and they would give a red, dark-blue, and red product respectively. Nitro blue tetrazolium develops rather slowly and allows close monitoring of the development. This feature allows tight control of the staining process and is often used in in situ hybridization.