Abstract
Investigations were made on technical conditions appropriate for Bessey's method. The optima of pH of alkaline phosphatases for serum, bone, kidney and intestine are 10.4,10.6,10.6 and 9.2,respectively. The incubating time should not exceed 30 minutes, since the rate of increase of activity is not lineal, but disturbed slightly after 25-30 minutes. The optimal substrate concentraions are 2×10^<-2> in serum, 5×10^<-3> in bone, 4×10^<-4> in kidney and 7×10^<-2> mol in intestine. Km calculated are as follows : Serum 1.3×10^<-4>, bone 1.8×10^<-5>, kidney 7.4×10^<-4>, intestine 7.4×10^<-3>
