A sensitive new method for measurement of guanase with 8-azaguanine in bicine bis-hydroxy ethyl glycine buffer as substrate.
Serum guanase activity has been considered as a possible specific indicator of hepatocellular diseases. However, no suitable method is available for routine clinical determination of serum guanase activity. Conventional assay methods are troublesome and inaccurate, since guanine and 8-azaguanine, the substrates of the enzyme, are scarcely soluble in water so that it is not possible to prepare a stable substrate solution of sufficient concentration for use in assays. A new method was developed for assay of guanase activity by direct colorimetric determination of ammonia. In this method, bicine bis-hydroxy ethyl glycine (dotite bicine) buffer is used for preparation of a stable substrate solution and with a fixed concentration of substrate of sufficient strength serum guanase can be measured sensitively and reproducibly. This assay system could be used as a routine clinical laboratory test in the diagnosis of liver damage.
D000619:Aminohydrolases / Q000097:blood*; D001375:Azaguanine; D002021:Buffers; D005260:Female; D005998:Glycine / Q000031:analogs & derivatives*; D006148:Guanine Deaminase / Q000097:blood*; D006801:Humans; D008297:Male; D013379:Substrate Specificity
D002021:Buffers; C027494:N,N-bis(2-hydroxyethyl)glycine; D000619:Aminohydrolases; D006148:Guanine Deaminase; D001375:Azaguanine; D005998:Glycine