Molecularly imprinted polymer enhances affinity and stability over conventional aptasensor for blood clotting biomarker detection on regimented carbon nanohorn and gold nanourchin hybrid layers

This study aims to develop a rapid and sensitive biomimetic biosensor for the early detection of bleeding disorders by sensing human blood clotting factor IX protein (FIX). Authors used a dual sensitive detection strategy to identify FIX deficiency in human plasma, by incorporating aptamer recognition mechanism with molecular imprinted polymer (MIP) technology. Amino-modified truncated 2′ fluoro-RNA aptamer was used as macro-monomer in MIP synthesis. Produced MIP nanoparticles were immobilized through carbodiimide on Archimedean spiral interdigitated electrode surface for the electrical detection. The sensitivity was enhanced by surface modification using carbon nanohorn and gold nanourchin. Incorporating these hybrid materials and MIP, the enhanced FIX sensor sensitivity was at 6.06E-6 µA fM−1 µm−2. It was found that MIP incorporated sensor has 3-folds enhanced sensitivity with 40 fM detection limit compared to the conventional aptasensor. Validations have been given by sensing FIX level from human plasma serum with 10.7 pM sensitivity and by enzyme-linked apta-sorbent assay at 8 pM as a sensitivity. Moreover, the specificity of sensor also has proven with discrimination of the analogues. This research produced a novel biosensor for FIX detection and justifies that aptamer embedded MIP plays a crucial role for high-performance protein recognition in bleeding diathesis.