We describe an enzymatic method for determining inorganic phosphate in serum and urine, with use of the “CentrifiChem.” The sample is mixed with a combined enzyme-substrate system consisting of the enzymes phosphorylase a, phosphoglucomutase, and glucose-6-phosphate dehydrogenase, the coenzyme NADP, the substrate glycogen, and adenosine 5’-monophosphate as the activator for phosphorylase. The i...

A method for spectrophotometric determination of nitrite and nitrate is described. This method is based on the reduction of phosphomolybdic acid to phosphomolybdenum blue complex by sodium sulfide. The obtained phosphomolybdenum blue complex is oxidized by the addition of nitrite and this causes a reduction in intensity of the blue color. The absolute decrease in the absorbance of the blue colo...

A new spectrophotometric method for the determination of minute amounts of cholesterol in tissues is described. This method is a modification of the Yoshimatsu reaction which is basedon the reduction of the yellow aqueoussolution of phospho-6tungstic-12-molybdic acid by a solution of cholesterol in concentrated sulfuric acid. The color of the resulting hydrosol of “molybdenum/tungsten blue” is ...