Abstract
An enzymatic assay method using inulase and sorbitol dehydrogenase (SDH) for determination of inulin in human serum and urine was described.
0.2ml of serum or 100 times diluted urine was mixed with lml of O.2M acetate buffer of pH5.Oand 20μl of inulase solution.Following incubation of the mixture for 60min.at 37°, 0.2ml of 1.0M triethanolamine buffer of pH8.2, 20μl of NADH soution and 20μl of LDH solution were added.
The mixture was then incubated further at 37° for ca.10min.lmmediately after addition of SDH solution (50μl), reduction of absorbance was measured at 340nm.
The linear relationship was observed between the amount of inulin and the absorbance.The average recovery of inulin added to the serum and urine were 98.7%and 100.2% respectively.The reproducibility of the me thod was 3.4% (C.V.) with 50.1±1.70mg/dl (mean±S.D.).Giucose present in the sample was found to be inert in the present method.
The results obtained by the present method corresponded with those obtained by the modified Heyrovsky's method.
