PRINCIPLE AND REFERENCE VALUES The Blood Lipid Test Strip (Dry Chemistry) use a timed-endpoint method to measure the Total Cholesterol (TC), High Density Lipoprotein Cholesterol (HDL) and Triglycerides (TG) concentrations in whole blood, serum or plasma. The concentration of Low Density Lipoprotein Cholesterol (LDL) is calculated by the values of TC, TG and HDL. The system monitors the change in absorbance at 620 nm at a fixed-time interval. The change in absorbance is directly proportional to the concentration of lipid in the specimen. TC: The free cholesterol is oxidized to cholesten-3-one and hydrogen peroxide by cholesterol oxidase. Peroxidase catalyzes the reaction of hydrogen peroxide with 4-aminoantipyrine and phenol to produce a colored quinoneimine product. HDL: The dextran slulphate/Mg2+ on the test strip precipitates the chylomicrons, VLDL and LDL, leaving HDL in the specimen. The cholesterol concentration of this HDL is then determined enzymatically, the same as TC. TG: Triglycerides in the specimen are hydrolyzed to glycerol and free fatty acids by the action of lipase. A sequence of three coupled enzymatic steps using glycerol kinase (GK), glycerophosphate oxidase (GPO), and peroxidase (POD) causes the oxidative coupling of 4-aminoantipyrine to form a blue dye. LDL; When the concentration of TG in the specimen is equal to or lower than 400mg/dL, LDL concentration can be calculated by the meter with the following equation: LDL=TC-HDL-TG/2.2(mmol/L); LDL=TC-HDL-TG/5(mg/dL)