OPD (o-phenylenediamine dihydrochloride) turns amber to detect HRP (Horseradish Peroxidase), which is often used to as a conjugated protein.
I-OPD (o-phenylenediamine dihydrochloride) iphenduka inhlaka ukuthola i-HRP (Horseradish Peroxidase), ejwayele ukusetshenziselwa njengeprotein ehlanganisiwe.