This method is based on the same reaction sequence as the Creatinine-PAP (phenol
aminophenazone) method (29) consisting of 4 consecutive enzymatic steps via creatininase, creatinase, sarcosine oxidase, and peroxidase, but using a different chromophore (2,4,6-triiodo-3-hydroxybenzoic acid) and a modified detergent composition.