Basic Concepts in Clinical Biochemistry-A Practical Guide.7z

N-acetylcysteine, thioglycerol, dithiothreitol, cysteine, etc. The reaction sample is
also added with an antibody specific to CK-M subunit which inhibits CK-M
monomer.

Creatine phosphateþADP⇄

CK

CreatineþATP

GlucoseþATP ⇄

Hexokinase

Glucose-6-PhosphateþADP

Glucose-6-PhosphateþNADP!

G 6 P dehydrogenase

6-phosphogluconolactone

þNADPH 2

33.4 Enzyme Reagents

Imidazole buffer (10 mM, pH 7.7)
Phosphocreatine (30 mM)
N-acetylcysteine (20 mM)
Magnesium acetate (10 mM)
Glucose (20 mM)
Glucose-6-phosphate dehydrogenase1.5 KU/L
Hexokinase2.5 KU/L
EDTA, ADP, and NADP (2 mM each)
AMP (5 mM)

33.5 Procedure

Keep enzyme reagent at 37C before use. Take 1 ml of this enzyme reagent in a
thermostated cuvette; add 0.05 ml of diluted serum/plasma, mix thoroughly, and
incubate exactly for 5 min at 37C and then read absorbance at 30 s intervals for
further 3 min.

33.6 Calculation

CK-MB activity/L of serum (IU/L)

¼ΔOD=min 6752 dilution factor

where, factor 6752 is obtained as:

132 33 To Measure Activity of Creatine Kinase in Serum