PEG-PtS₂ nanosheet-based fluorescence biosensor for label-free human papillomavirus genotyping

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Platinum disulfide (PtS2) nanosheets offer potential for biosensing applications.
• Efficient large-scale production and aqueous dispersion of PtS2 nanosheets are crucial for practical use.
• Fluorescence quenching by nanomaterials is a promising mechanism for sensitive detection.

Purpose of the Study:

• To develop a simple and efficient method for large-scale production of polyethylene glycol-modified PtS2 (PEG-PtS2) nanosheets.
• To investigate the fluorescence quenching mechanism of PEG-PtS2 nanosheets with DNA probes.
• To establish a sensitive and cost-effective biosensor for human papillomavirus (HPV) genotyping.

Main Methods:

• Ultrasonication-assisted liquid exfoliation for PtS2 nanosheet production.
• Surface modification with polyethylene glycol (PEG) for aqueous dispersion.
• Fluorescence spectroscopy to study the interaction between PEG-PtS2 nanosheets and FAM-labeled DNA probes.
• Development of a mix-and-detect assay for DNA determination based on differential fluorescence quenching.

Main Results:

• Successfully produced large-scale PEG-PtS2 nanosheets with improved aqueous dispersion.
• Identified a static quenching effect mechanism for fluorescence quenching of DNA probes by PEG-PtS2 nanosheets.
• Demonstrated a sensitive HPV genotyping assay with a limit of detection of 0.44 nM and a linear range of 0.05-10 nM.
• Achieved easy genotyping of HPV without probe immobilization or washing steps.

Conclusions:

• The developed PEG-PtS2 nanosheets are suitable for sensitive and selective DNA detection.
• The proposed mix-and-detect method offers a simple, low-cost, and efficient strategy for molecular diagnostics.
• This approach holds promise for developing point-of-care diagnostic tools for infectious diseases like HPV.