Enhanced detection of HER2 through a layer-by-layer strategy using a TiVC MXenes/Au nanocomposite amplified analytical biosensor for precise cancer biomarker monitoring

Abstract

This research work explores the development and application of layer-by-layer modified electrochemical apta-sensor for the precise monitoring of HER2, a crucial biomarker associated with breast cancer. The surface of the screen-printed carbon electrode was modified with gold nanoparticle (Au-NP) and TiVC MXene catalyst plus Pb²⁺ loaded aptamer (SPCE/TiVC-MXene/Au NPs/Pb²⁺-aptamer), which showed a high selectivity and affinity toward HER2 and offered a sensitive detection platform. The MXene nano-layer was synthesized and characterized by FT-IR, MAP, EDS, and TEM methods and used as a substrate to improve electrochemical conductivity and loading of biological recognition element. The difference of stripping signals of the Pb²⁺ from the SPCE/TiVC-MXene/Au NPs/Pb²⁺-aptamer before and after incubation in HER2 solution was selected as analytical response to achieve a reliable and quantitative analysis for HER2 concentrations. The results demonstrate a linear dynamic range of 1.0–1200 pg/mL for monitoring of HER2 with limit of detection of 50 fg/mL. Agood affinity of fabricated aptasensor to HER2 in the presence some other biomarkers such as PR, ER, and CEA confirmed the selectivity of the fabricated biosensor towards HER2.