Abstract
Simple and rapid detection of disease-related bio-markers are significant for early clinical diagnosis and can potentially improve the survival rate. However, establishing a high-specificity colorimetric detection method for bio-markers are still challenges due to their inevitable natural antibody used or enzymatic labeling. Herein, a cost-efficient and easy-to-use approach, which called dual molecular imprinting immunosandwich colorimetric strategy (DMI-ICS) was constructed for detection alpha-2-macroglobulin (alpha 2MG) by janus imprinted nanoparticles. The unique detection principle was contained with two mimic antibody parts, the first part was alpha 2MG glass slides molecularly imprinted material (GS-MIP) as a "Separation antibody", which can specifically rapid separate the protein in the complex sample; Another part was asymmetrically modified janus molecularly imprinted gold nanoparticles nanozyme (J-GNPs-MIP) as a "Detection antibody", which has the properties of specific recognition and catalytic substrate color performance at the same time. The concentration of alpha 2MG can be determined by the substrate color changes and observed with naked eyes. Under the optimized conditions, the DMI-ICS had a great performance and offering lower relative standard deviation (RSD, 7.69%), good linear range (0.297-130 mu g/mL, R2 = 0.994), high imprinting factor (IF: 3.74) with lower detection limit (0.089 mu g/mL). This strategy provides an easy operation and low cost signal readout method for direct detection and separation of alpha 2MG in human serum samples, which is a versatile tool for point-of-care diagnosis, while also offering a new perspective on antibody simulation technology, multifunctional antibody preparation and contribute to detection of disease-related bio-marker in nonspecialized laboratory infrastructure. (C) 2021 Elsevier B.V. All rights reserved.

Keywords Plus：ALPHA(2)-MACROGLOBULINNANOMATERIALSIMMUNOASSAYCANCERELISAASSAY

Published in ANALYTICA CHIMICA ACTA，Volume 1184；10.1016/j.aca.2021.339039，NOV 1 2021