Aptamer Pseudoknot-Functionalized Electronic Sensor for Reagent less and Single-Step Detection of Immunoglobulin E in Human Serum

The development of electronic sensors with minimized usage of reagents and washing steps in the sensing protocols will significantly facilitate the detection of biomolecules. In this work, by using a new pseudoknot,design of,the aptamer probes, the construction of an electronic sensor for reagentless and single-Step detection of immunoglobulin E (IgE) in human serum is described. The pseudoknot aptamer-probes-are self-assembled On the disposable electrode ,surface. The association of IgE, with the aptamer probes leads to conformational changes of the pseudoknot aptamer structures and brings, the redox-tags in close proximity to the electrode, resulting in amplified Current response for monitoring IgE. The effects: of the pseudoknot structure and the immobilitation concentration of the aptamer probes on the sensor performance are evaluated. Under optimal conditions,;the detection limit for IgE is estimated to be 60 pm. The sensor is also selective:land can be employed to detect IgE in human serum samples. The developed,sensor achieve reagentless, washing free and low-cost (with the disposable,electrode) electrochemical,detection of proteins, making this device a convenient sensing :platform for the monitoring of different biomarkers When coupled with the appropriate aptamer, probes.