PURPOSE: To diagnose an arteriosclerosis by measuring α-lipoprotein using a reagent for determining hydrogen peroxide consisting of p-halophenol and 4-aminoantipyrin.
CONSTITUTION: Cholesterol content in α-lipoprotein is colorimetrically measured by using a reagent combination for determining H2O2 consisting of p-halophenol of the formula shown, where X signifies halogen, and 4-aminoantipyrin. That is, cholesterol ester is converted to free cholesterol by cholesterol ester hydrolase, and cholesterol oxidase is reacted with the free cholesterol to oxidize it to Δ4-cholestenone and H2O2. Then, the quantitatively formed H2O2 is reacted with the reagent in the presence of peroxidase to oxidize and condense the 4-aminoantipyrin and the phenol. The formed red quinone color is colorimetrically measured. Thus, even trace amounts of α-lipoprotein in serum can be accurately and rapidly measured, and arteriosclerosis may be diagnosed by the ratio of this value and β-lipoprotein.
YAMANISHI KAZUHIKO
TOKUDA KUNIAKI
HANADA TOSHIROU
