Abstract: P1281 DEVELOPMENT OF A NOVEL HOMOGENEOUS ASSAY FOR QUANTIFICATION OF SMALL DENSE LDL...
1
Poster - EPIDEMIOLOGY OF CVD - Lipoprotein Particles and Heart Disease Abstract: P1281 Citation: Atherosclerosis Supplement 2009, Vol. 10, Issue 2 DEVELOPMENT OF A NOVEL HOMOGENEOUS ASSAY FOR QUANTIFICATION OF SMALL DENSE LDL CHOLESTEROL Y Ito 1 , M Fujimura 1 , M Ohta 1 , T Hirano 2 1 Denka Seiken Co., Ltd., Tokyo; 2 Showa University, School of Medicine, Tokyo Objectives We developed a fully automated assay for quantification of small dense LDL-cholesterol (sd LDL-C). We describe the design of our new assay and report its verification results. Methods Our new assay for sd LDL-C employs two liquid, ready-to-use reagents containing 3 key ingredients: 1) a polyoxyethylene benzylphenyl ether selectively decomposing chylomicron, VLDL and HDL, 2) a polyoxyethylene distyrenelphenyl ether selectively binding to sd LDL to protect it from the action of enzymes, and 3) sphingomyelinase possessing higher affinity to larger LDL than sd LDL. These ingredients eliminate the other lipoproteins than sd LDL. Cholesterol from such non-sd LDL lipoproteins are degraded to water and oxygen by enzymatic reactions. At the 2 nd step, cholesterol is released from sd LDL and lead to color development. The new assay can be applied to serum and plasma, and is completed in 10 minutes without any off-line pretreatment. Results Precision study revealed CVs of 0.8 – 1.7%. Linearity was observed up to 100 mg/dL. No significant interference was seen with bilirubin, hemoglobin, ascorbate. When compared to the traditional ultracentrifugation method using 60 samples, the regression analysis showed: y = 0.99x – 3.4 , r = 0.954. Test samples were stable for 7 days in a refrigerator. Consistent results were obtained with the samples subjected to repeated freezing and thawing. In a case-control study, sd LDL-C measured by this new assay was significantly higher in the CAD group than the non-CAD group (p<0.05). Conclusions Our new assay was verified to possess robust and reliable performance. This new assay may contribute to the wide spread use of sd LDL-C. Funding: The study was financially supported by Denka Seiken Co., Ltd.
Transcript of Abstract: P1281 DEVELOPMENT OF A NOVEL HOMOGENEOUS ASSAY FOR QUANTIFICATION OF SMALL DENSE LDL...
Poster - EPIDEMIOLOGY OF CVD - Lipoprotein Particles and Heart Disease
Abstract: P1281
Citation: Atherosclerosis Supplement 2009, Vol. 10, Issue 2
DEVELOPMENT OF A NOVEL HOMOGENEOUS ASSAY FOR QUANTIFICATION OF SMALL DENSE LDL CHOLESTEROL
Y Ito1, M Fujimura1, M Ohta1, T Hirano2
1Denka Seiken Co., Ltd., Tokyo; 2Showa University, School of Medicine, Tokyo
Objectives We developed a fully automated assay for quantification of small dense LDL-cholesterol (sd LDL-C). We describe the design of our new assay and report its verification results. Methods Our new assay for sd LDL-C employs two liquid, ready-to-use reagents containing 3 key ingredients: 1) a polyoxyethylene benzylphenyl ether selectively decomposing chylomicron, VLDL and HDL, 2) a polyoxyethylene distyrenelphenyl ether selectively binding to sd LDL to protect it from the action of enzymes, and 3) sphingomyelinase possessing higher affinity to larger LDL than sd LDL. These ingredients eliminate the other lipoproteins than sd LDL. Cholesterol from such non-sd LDL lipoproteins are degraded to water and oxygen by enzymatic reactions. At the 2nd step, cholesterol is released from sd LDL and lead to color development. The new assay can be applied to serum and plasma, and is completed in 10 minutes without any off-line pretreatment. Results Precision study revealed CVs of 0.8 – 1.7%. Linearity was observed up to 100 mg/dL. No significant interference was seen with bilirubin, hemoglobin, ascorbate. When compared to the traditional ultracentrifugation method using 60 samples, the regression analysis showed: y = 0.99x – 3.4 , r = 0.954. Test samples were stable for 7 days in a refrigerator. Consistent results were obtained with the samples subjected to repeated freezing and thawing. In a case-control study, sd LDL-C measured by this new assay was significantly higher in the CAD group than the non-CAD group (p<0.05). Conclusions Our new assay was verified to possess robust and reliable performance. This new assay may contribute to the wide spread use of sd LDL-C. Funding: The study was financially supported by Denka Seiken Co., Ltd.
