An electrochemical aptasensor for monitoring HER2-positive breast cancer biomarker

Abstract

The proposed research showcases a bioelectrode design for an aptasensor with an optimised protocol for a highly favourable binding environment. It utilises a 76-nucleotide long ssDNA aptamer as a recognition element to detect HER2+ breast cancer biomarker with high specificity and sensitivity. Screen Printed Gold Electrodes are used to build the sensor. Electroanalytical techniques namely Cyclic Voltammetry is utilised to clean the SPEs and Electrochemical Impedance Spectroscopy to study the aptamer-HER2 binding on the electrode surface.

HDT (1,6-Hexanedithiol) is employed as a blocking agent to prevent the non-specific adsorption. Due to the ineffectiveness of Co-immobilisation, a Layer-by-layer incubation is adopted . Furthermore, maintaining the 3-D structure of the aptamer and performing experiments below room temperatures were found to be critical for HER2 stability and effective binding.

The outcome is an electrochemical aptasensor for real-time HER2 detection, which can aid clinicians in monitoring treatment efficacy ultimately leading to improved patient outcomes.