Electrochemical Aptasensor for Determination of Mucin 1 by P-Aminophenol Redox Cycling

Abstract

Mucins, produced by epithelial tissues in most metazoans, have served as reliable molecular biomarkers for cancer diagnosis and prognosis. In this work, a competitive electrochemical aptasensor is reported for the determination of mucin 1 protein by p-aminophenol redox cycling. Specifically, the conjugates produced between biotinylated mucin 1 and streptavidinalkaline phosphatase were captured by an anti-mucin 1 aptamer-modified electrode, which induced the production of electrochemically active p-aminophenol from the p-aminophenyl phosphate substrate. The resulting p-aminophenol was cycled by tris(2-carboxyethyl) phosphine after its oxidization on the electrode, thus enabling an increase in the anodic current. Because the mucin 1 competed with the conjugates to bind the anchored aptamer, the signal decreased with an increase in protein concentration between 0.5 and 6 nM. As a result, a detection limit of 0.1 nM was achieved. To demonstrate the viability of the method for real samples, the effects of glucose, blood serum, and other proteins (e.g., thrombin, human immunoglobulin G, and Zn 7 -metallothionein) were investigated.

Functionalized Thiophene-Based Aptasensors for the Electrochemical Detection of Mucin-1

“…The correlation between MUC1-derived “cancer antigen epitopes” and patient prognosis is therefore a critical element of cancer screening. Indeed, serial CA 15-3 measurements are commonly used to detect early recurrence and monitor metastatic breast cancer patients during follow-up. − Traditional methods such as enzyme-linked immunosorbent assay, dot blotting, western blotting, immunofluorescence, and immunohistochemistry have been utilized for the detection of MUC1, but they are time-consuming, labor-intensive, and require a high level of expertise and dedicated instrumentation, therefore limiting their use in real-time, point-of-care clinical diagnostics. , For widespread adoption of MUC1-based screening of cancer, it is important to develop novel sensors for the rapid, sensitive, and selective detection of MUC1. Electrochemical detection methods have been researched in recent years as a good alternative to more traditional methods of biological detection due to their ease of use, rapid response, and high selectivity and sensitivity. − …”