A Low-Cost Paper-Based Electrochemical Aptasensor for HER-2 Detection Using Ti₃C₂T_x MXene.

Area of Science:

• Biomedical Engineering
• Nanomaterials
• Biosensors

Background:

• Breast cancer is a leading cause of mortality in women globally.
• There is a critical need for early, rapid, and cost-effective diagnostic methods.
• Human epidermal growth factor receptor 2 (HER-2) is a key biomarker for breast cancer progression.

Purpose of the Study:

• To develop a low-cost, paper-based electrochemical aptasensor for HER-2 detection.
• To utilize Ti3C2Tx MXene for enhanced sensor performance.
• To provide a tool for accessible, point-of-care breast cancer diagnostics.

Main Methods:

• Fabrication of a sensor on a carbon screen-printed paper electrode (CSPPE).
• Modification of the electrode with Ti3C2Tx MXene for aptamer immobilization.
• Covalent attachment of HER-2 aptamers and use of methylene blue as a redox mediator.

Main Results:

• The aptasensor achieved a wide linear detection range (10 fg/mL to 100 μg/mL).
• Demonstrated a low limit of detection (LOD) of 9.3 fg/mL and limit of quantification (LOQ) of 28.4 fg/mL.
• Exhibited high selectivity, reproducibility, stability, and sensitivity (10.05 μA/fg/mL/mm2).

Conclusions:

• The MXene-modified paper-based aptasensor is a promising platform for sensitive and specific HER-2 detection.
• This technology offers potential for rapid, cost-effective, point-of-care breast cancer diagnostics.
• The sensor's stability and ease of use support its translation to clinical settings.