MULTIENZYME CONTROL SERUM (SERACLEAR-HE) CONTAINING HUMAN ENZYMES FROM ESTABLISHED CELL-LINES AND OTHER SOURCES .1. PREPARATION AND PROPERTIES

We have developed a new multienzyme control serum, Seraclear-HE, which was designed to function not only as an accuracy and precision contro l serum but also as an intermethod calibrator for unifying interlabora tory clinical enzyme data in terms of reference method values. Seracle ar-HE contains as analytes the following enzymes of human origin only: aspartate aminotransferase (AST, EC 2.6.1.1) and lactate dehydrogenas e (LD, EC 1.1.1.27) from erythrocytes; alanine aminotransferase (ALI, EC 2.6.1.2) from a hepatoma cell line; alkaline phosphatase (ALP, EC 3 .1.3.1) from an amnion cell line; creatine kinase (CK, EC 2.7.3.2) fro m an embryo kidney cell line; gamma-glutamyltransferase (GGT, EC 2.3.2 .2) from a macrophage cell line; and amylase (AMY, EC 3.2.1.1) from ur ine and saliva. The seven partly purified enzymes were lyophilized in partially delipidated human serum containing sucrose (50 g/L), pyridox al 5'-phosphate (30 mmol/L), and other stabilizers. The material is st able for at least 2 years at temperatures less than or equal to 10 deg rees C. For two concentrations of this preparation, reference method v alues (mainly International Federation of Clinical Chemistry and Japan Society of Clinical Chemistry) obtained at both 30 degrees C and 37 d egrees C are assigned.