Hand-Fabricated CNT/AgNPs Electrodes using Wax-on-Plastic Platforms for Electro-Immunosensing Application

Area of Science:

• Electrochemistry
• Materials Science
• Biosensing

Background:

• Flexible and inexpensive electronic sensors are crucial for biochemical and biomedical applications.
• Existing fabrication methods can be costly and complex, limiting widespread use.
• There is a need for simple, adaptable sensor fabrication techniques.

Purpose of the Study:

• To explore the hand fabrication of carbon nanotube (CNT) modified silver nanoparticle (AgNPs) electrodes on flexible substrates.
• To evaluate the electrochemical performance and application of these electrodes in immunosensing.
• To demonstrate the detection of a cancer biomarker, carcinoembryonic antigen (CEA).

Main Methods:

• Utilizing wax-on-plastic platforms with polyethylene terephthalate substrates for electrode patterning.
• Hand-painting silver nanoparticle (AgNPs) ink for conductive layers and drop-casting CNTs to enhance electrochemical signals.
• Characterization using scanning electron microscopy and electrochemical techniques (cyclic voltammetry, differential pulse voltammetry, amperometry).

Main Results:

• Successfully fabricated flexible CNT/AgNPs electrodes via a simple hand-painting method.
• CNT/AgNPs electrodes exhibited superior electrochemical performance (faster, higher, more selective) compared to unmodified AgNPs electrodes.
• Demonstrated successful application in electrochemical immunosensing for carcinoembryonic antigen (CEA) detection.

Conclusions:

• Hand-fabricated CNT/AgNPs electrodes offer a cost-effective and flexible platform for electrochemical sensing.
• The integration of CNTs significantly enhances electrode performance for biosensing applications.
• This approach provides a promising method for developing sensitive and selective diagnostic tools, with a low detection limit for CEA (0.46 ng/mL).