Determination of alpha-amylase, trypsin and lipase in duodenal fluid: comparison of methods.

The three most important enzymes present in duodenal fluid, alpha-amylase, trypsin and lipase, were determined by two different methods. Various dilution fluids for these determinations were compared. Some kinetic data are described together with the reproducibility of the assays. For alpha-amylase the Phadebas method was compared with an UV method. Trypsin was determined using an immunoreactive trypsin test and a titrimetric method, while lipase was determined with a titrimetric method and a Cu-soap method. There was very good agreement between the two alpha-amylase methods and between the two trypsin determinations. There was also good agreement between both lipase methods. The advantages and disadvantages of all the methods are discussed.