Silica nanoparticle assists determining liver cancer gene sequence on interdigitated electrode surface

Area of Science:

• Biosensors and Nanotechnology
• Molecular Diagnostics
• Biomedical Engineering

Background:

• Accurate detection of cancer-related genes is crucial for early diagnosis and treatment monitoring.
• Existing biosensing methods often require complex labeling or lack sufficient sensitivity and specificity.
• Silica nanoparticles (SiNPs) offer versatile platforms for biosensor surface modification due to their unique properties.

Purpose of the Study:

• To develop a high-performance interdigitated electrode (IDE) biosensing surface using self-assembled silica nanoparticles (SiNPs).
• To evaluate the complementation of the hairpin forming region of the Mitoxantrone resistance gene 7 (MXR7), a liver cancer-related gene.
• To establish a label-free, sensitive, and specific method for quantifying target DNA sequences.

Main Methods:

• Functionalization of IDEs with 3-aminopropyl triethoxysilane.
• Conjugation of SiNPs with probe sequences and their capture onto the functionalized IDE surface.
• Quantification of MXR7 gene sequences via electrochemical measurements and analysis of current response.

Main Results:

• A significant increment in current response was observed upon successful complementation of the target DNA.
• Achieved a limit of detection as low as 1-10 fM for target DNA, comparable to fluorescent-based methods.
• Demonstrated high specificity, clearly distinguishing complementary sequences from mismatched ones.

Conclusions:

• The SiNP-modified IDE biosurface provides a sensitive and label-free platform for gene sequence detection.
• This strategy is effective for quantifying MXR7, aiding in the determination of liver cancer progression.
• The developed detection strategy holds potential for application in other gene sequence complementation studies.