A DNA biosensor based on graphene paste electrode modified with Prussian blue and chitosan.

Area of Science:

• Electrochemistry
• Nanomaterials Science
• Biotechnology

Background:

• Graphene paste electrodes offer unique electrochemical properties.
• Prussian blue (PB) and chitosan are effective modifiers for biosensing applications.
• Developing sensitive and selective DNA detection methods is crucial for diagnostics.

Purpose of the Study:

• To develop a chemically modified graphene paste electrode for enhanced DNA detection.
• To investigate the electrochemical properties of the modified electrode.
• To evaluate the electrode's performance in detecting complementary DNA.

Main Methods:

• Preparation of a graphene paste electrode modified with Prussian blue and chitosan.
• Electrochemical characterization using cyclic voltammetry.
• Optimization of electrode composition and probe DNA immobilization.
• Detection of DNA hybridization through daunomycin intercalation.

Main Results:

• The modified electrode demonstrated superior voltammetric response for complement DNA compared to ordinary carbon paste electrodes.
• The combination of graphene and Prussian blue significantly enhanced the electrode's current response.
• Successful binding of single-stranded DNA (ssDNA) and detection of double-stranded DNA (ds-DNA) hybridization.
• A significant change in current was observed upon daunomycin intercalation with ds-DNA.

Conclusions:

• The developed chitosan and Prussian blue-modified graphene paste electrode is a promising platform for sensitive and selective DNA detection.
• The synergistic effect of graphene and Prussian blue enhances electrochemical performance.
• This modified electrode holds potential for applications in molecular diagnostics and biosensing.