nitrophenols and 2-amino-2-methyl-1-3-propandiol

Three sets of interrelated specimens containing alkaline phosphatase (ALP) were analyzed: CAP 1977 Enzyme Survey serum, human serum supplemental with calf intestinal ALP, and human serum with increased human liver ALP. Five quite distinct ALP methods were used. In addition, fresh serum from volunteer blood donors and serum from patients with increased serum ALP activities were examined by each of these five methods. Conversion factors for the five different methods based on results from calf-intestine-supplemented interrelated specimens could not be used to interconvert results for fresh human serum. However, the interrelated specimens with increased human liver ALP made interconversion of results for fresh human serum possible.

Topics: Alkaline Phosphatase; Animals; Cattle; Creatine; Female; Humans; Intestines; Isoenzymes; Kinetics; Laboratories; Liver; Male; Nitrophenols; Organophosphorus Compounds; Phenolphthaleins; Propylene Glycols; Quality Control; Sex Factors; Thymolphthalein

The inhibitory effect of inorganic phosphate on the activity determination of isoenzymes of alkaline phosphatase (AP) in diethanolamine (DEA), glycine and 2-amino-2-methyl-1,3-propandiol (AMPD) buffer was studied. This effect depends on the buffer used and isoenzyme investigated. Especially the placental isoenzyme is inhibited; the inhibitory effect in DEA buffer is stronger than in the other buffers used. The requirement of purity for 4-nitrophenylphosphate with respect to its content of inorganic phosphate and conclusions for using control sera enriched with AP isoenzymes are discussed.

Topics: 4-Nitrophenylphosphatase; Alkaline Phosphatase; Bone and Bones; Buffers; Ethanolamines; Female; Glycine; Humans; Intestine, Small; Isoenzymes; Liver; Nitrophenols; Organophosphorus Compounds; Phosphates; Placenta; Pregnancy; Propylene Glycols; Quality Control