Abstract
Using the chromogenic substrate 3,3′‐dichlorophenylsulfonphthaleinyl‐N‐acetyl‐β‐d‐glucosaminide for the activity determination of plasma β‐N‐acetylhexosaminidase (Hex), the temperature conversion factors (TCF) offer a highly significant positive correlation with the relative proportion of Hex B isoenzyme (P < 0.001). The calculation of TCF 37°/25°C allows the isoenzyme composition of Hex to be determined quickly and cheaply. The results may be superimposed over those obtained in a previously described method based on the calculation of the enzyme’s activation energy using four temperatures. However, the use of TCF 37°/30°C does not appear to comply with the required demands. J. Clin. Lab. Anal. 14:327–329, 2000. © 2000 Wiley‐Liss, Inc.
Keywords: plasma β‐N‐acetylhexosaminidase, isoenzymes, temperature conversion factors
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