Graphene Oxide-Gold Star Construct on Triangular Electrodes for Alzheimer's Disease Identification

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Molecular Diagnostics

Background:

• Nanomaterials significantly enhance biosensor selectivity and sensitivity for medical diagnosis.
• Alzheimer's disease (AD) diagnosis can be improved through advanced biosensing technologies.
• MicroRNA-137 (miRNA-137) has been identified as a potential biomarker for AD.

Purpose of the Study:

• To develop a novel, low-cost biosensor for the specific detection of miRNA-137 for Alzheimer's disease (AD) diagnosis.
• To utilize graphene oxide (GO) and gold nanostars (GNS) for enhanced miRNA detection.
• To establish a sensitive and selective sensing strategy for early AD detection.

Main Methods:

• Fabrication of triangular electrodes modified with graphene oxide (GO).
• Conjugation of gold nanostars (GNS) with capture miRNA-137 and immobilization onto the GO surface via an amine linker.
• Electrochemical detection of target miRNA-137 hybridization using the developed biosensor.

Main Results:

• The biosensor achieved a detection limit of 10 fM and a sensitivity of 1 fM for miRNA-137.
• High specificity was demonstrated, with no significant response to control sequences (miRNA-21) or mismatched miRNA-137.
• A high regression coefficient (0.9038) indicated a reliable linear response.

Conclusions:

• The developed graphene oxide-constructed triangular electrode biosensor, enhanced with gold nanostars, offers a highly sensitive and specific method for detecting miRNA-137.
• This nanotechnology-based approach shows significant potential for the early and accurate diagnosis of Alzheimer's disease (AD).
• The low-cost and effective biosensing strategy contributes to advancements in molecular diagnostics for neurodegenerative diseases.