Plasma beta-N-acetylhexosaminidase isoenzyme composition and temperature conversion factors

Using the chromogenic substrate 3,3'-dichlorophenylsulfonphthaleinyl-N-acet yl-beta -D-glucosaminide for the activity determination of plasma beta -N-a cetylhexosaminidase (Hex), the temperature conversion factors (TCF) offer a highly significant positive correlation with the relative proportion of He x B isoenzyme (P < 0.001). The calculation of TCF 37<degrees>/25 degreesC a llows the isoenzyme composition of Hex to be determined quickly and cheaply . The results may be superimposed over those obtained in a previously descr ibed method based on the calculation of the enzyme's activation energy usin g four temperatures. However, the use of TCF 37 degrees/ 30 degreesC does n ot appear to comply with the required demands. J. Clin. Lab. Anal. 14:327-3 29, 2000. (C) 2000 Wiley-Liss, Inc.