Development of a Sensitive Electrochemical Aptasensor for Non‐Small Cell Lung Cancer Extracellular Vesicle Detection

Abstract Lung cancer is challenging to diagnose due to late symptom manifestation, necessitating non‐invasive, point‐of‐care detection tools. Extracellular vesicles (EVs), nano‐sized particles present in body fluids such as exhaled breath, offer a promising diagnostic route. EVs carry molecular cargo from their parent cells, including cancer‐specific protein biomarkers, making them ideal targets for early detection. This study presents an electrochemical aptasensor platform for detecting EVs associated with non‐small cell lung cancer. A microfabricated gold chip functionalized with AptTex, a thiol‐modified aptamer targeting the CD44 biomarker, is developed. Electrochemical impedance spectroscopy confirms aptamer immobilization, and the platform successfully detectss extracellular vesicles in vitro from non‐small cell lung cancer cells with a detection limit of 3.0 × 10 ⁶ particles/mL and Δ R _et = 476 ± 192 Ω. Calibration plots for generic extracellular vesicles demonstrated a detection limit of 7.0 × 10 ⁶ particles/mL. The platform shows sensitivity, reproducibility, and minimal sample requirements. These findings demonstrate the potential of this aptasensor for future integration into a portable disease breathalyser, enabling non‐invasive early detection of lung cancer.