An Improved Method for the Quantitation of Apolipoprotein B and Apolipoprotein A-1 in Dried Blood Spots

Abstract

An extraction protocol has been developed to elute apolipoprotein B (apo B) and apolipoprotein A-1 (apo A-1) from dried blood spots with assay of the extracted apolipoproteins by automated immunoturbidimetry. Various extraction media were investigated to assess their elution efficiency and the optimum medium was found to be deionized water. Studies on the rate of elution suggested both apolipoproteins were eluted readily in less than an hour with a recovery of 71% for apo B and 65% for apo A-1. Extracted apo B but not apo A-1 was found to be stable for 24 h when kept at 4°C. The within-batch coefficients of variation (CV) for the combined extraction and assay of apo B were found to be 5·9% and 8·5% at 0·6 g/L and 1·2 g/L respectively. The CVs for apo A-1 were found to be 7·4% at 0·7 g/L and 8·9% at 1·5 g/L. Antiserum from three sources (Immuno, Incstar and Bayer) was investigated for immunoreactivity with apo B and apo A-1 and cross-reactivity with red blood cells was also assessed. Although the antisera from the three companies showed similar immunoreactivity towards apo B and apo A-1, antiserum from Bayer was found to cross-react with red cells.

Effects of Promoting Longer-Term and Exclusive Breastfeeding on Cardiometabolic Risk Factors at Age 11.5 Years

“…Circulating levels of adiponectin and apolipoprotein A1 (apoA1) were each quantified from one 3-mm diameter disc (≈ 3 μL of blood) per child using existing assay kit reagents (adiponectin human ELISA, EIA4177, DRG International Inc, New Jersey, and Turbox APO A1 catalogue number 67561, Orion Diagnostica, Finland, respectively) and validated methods for blood spots. 23, 24 We did not assay HDL-C directly, as the direct measurement of cholesterol from dried blood spots is not straightforward or reliable. 25 The assay performance characteristics are given in Supplemental Table 1.…”

Screening for hypercholesterolaemia in 10,000 neonates in a multi-ethnic population

“…The aims of this research were to apply an improved immunoturbidimetric method for apoB and A-1 in dried blood spots to the screening of neonates for hyperlipidaemias [19]. The screening was speci®cally aimed at identifying infants with FH, but the techniques would also identify infants with familial defective apoB-100, familial combined hyperlipidaemia and polygenic hyperlipidaemia.…”

Smart proteolysis samplers for pre‐lab bottom‐up protein analysis – Performance of on‐paper digestion compared to conventional digestion

“…One of the first-mentioned immunometric methods to determine protein concentration from DBS was that of C-reactive protein using enzyme-linked immunoassay [5]. Soon other immunometric assays for protein determination followed for other protein analytes; alpha1antitrypsin, various antibodies [6,7], and apolipoprotein B and apolipoprotein A-1 [8] are only a few of the available examples.…”