ZnO/SiO₂ core/shell nanowires for capturing CpG rich single-stranded DNAs.

Area of Science:

• Materials Science and Nanotechnology
• Biomedical Engineering
• Molecular Biology

Background:

• Atomic Layer Deposition (ALD) offers conformal ultrathin coatings on complex nanostructures.
• Zinc oxide (ZnO) nanowires are versatile platforms for biosensing applications.
• CpG-rich single-stranded DNA (ssDNA) is relevant for cancer biomarker detection.

Purpose of the Study:

• To optimize ALD cycles for ZnO/SiO2 core/shell nanowires for enhanced ssDNA capture.
• To fabricate a microfluidic device using these modified nanowires for ssDNA detection.
• To investigate the relationship between ALD parameters and ssDNA capture efficiency.

Main Methods:

• Surface modification of ZnO nanowires using ALD with varying cycle numbers.
• Fabrication of a ZnO/SiO2 core/shell nanowire microfluidic device.
• Statistical analysis of structural changes and ssDNA capture efficiency.
• Biomolecule capture experiments with CpG-rich ssDNA.

Main Results:

• ALD successfully created conformal SiO2 shells on ZnO nanowires.
• Optimal ALD cycles were identified to tune surface properties and create effective trapping sites.
• The fabricated ZnO/SiO2 nanowire device achieved a high ssDNA capture efficiency of 86.7%.
• Structural analysis correlated ALD cycles with capture performance.

Conclusions:

• Optimized ALD on ZnO nanowires is effective for fabricating high-performance ssDNA capture devices.
• The core/shell nanowire design shows significant potential for biomedical applications, particularly in cancer gene analysis.
• This approach facilitates the development of advanced biosensors for detecting specific DNA sequences.