Analyzing duplex formation with abdominal aortic aneurysm biomarker on palladium nanocube attached interdigitated electrodes

Abdominal aortic aneurysm (AAA) is an inflated region in the lower part of body’s major artery (the aorta). Traditional screening methods of imaging are expensive, and researchers focus on alternative methods of biomarker screening with AAA detection. This research developed a method for duplex detection of two AAA biomarkers, namely, insulin like growth factor 1 (IGF1) and IGF binding proteins 1 (IGFBP1) for diagnosing AAA on palladium nanocube-modified interdigitated electrode (IDE) sensor. The probed surface with anti-IGFBP1 monoclonal antibody and anti-IGF1 aptamer was created on aminated palladium and performed the sensing with anti-IGF1 and anti-IGFBP1 antibodies. Palladium improved the probe attachment with aptamer-antibody on IDE surface and significantly enhanced the interactions of IGF1 and IGFBP1. The probe modified surface detects IGF1 and IGFBP1 as low as 10 fg/mL and 10 pg/mL with the R
2
values of 0.9183 [y = 0.1105x
2
– 0.2323x + 0.2181 R
2
= 0.9975], and 0.9032 [y = 0.1123x
2
– 0.2893x + 0.236 R
2
= 0.9953], respectively, on a linear regression. Further, control performances with closely related biomarkers namely C-reactive protein (CRP), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and complementary aptamer sequence did not enhance the current and confirm specific detections IGF1 and IGFBP1. In addition, there is a current increment that was noted in IGF1 and IGFBP1 spiked serum samples without any interferences display the selective detection.