Multilayer Dry Film Element for Clinical Diagnosis Based on Enzymatic Triglycerides Assay

Abstract

Multilayer film elements are used for clinical diagnosis. They contain all chemicals for colorimetric reaction sequence. To assay the concentration of TG (Triglycerides) in blood is important in relation to adiposis and heart diseases. We have developed a multilayer film element for determining the concentration of TG based on enzymatic analysis. There are two major assay methods of TG. TG is hydrolyzed to glycerine and fatty acids by LPL (Lipoprotein lipase) . Then, glycerine is phospholylated by GK (Glycerol kinase) . These two steps are same, but the third step is different between two methods. Glycerophosphate is oxidized by GPO (Glycerophosphate oxidase) and H₂O₂ is formed. H₂O₂, POD (Peroxidase) and leuco precursor form dye. On the other hand, NADH is produced by glycerophosphate and GPDH (Glycerophosphate dehydrogenase) . NADH, DI (Diaphorase) and NTB (Nitrotetrazolium blue) form another dye. Our method is the latter, however, this method has some defects. Because GPDH is expensive, we have changed the assay method of TG. We report some advantages of the method using GPO. It needs four minutes to determine the concentration of TG, while the method using GPDH needs five minutes per one specimen. By using this multilayer film element, we can obtain the concentration of TG easily without any other experiments except for setting the multilayer film element and specimen to an analyzer.