Binding-induced fluorescence turn-on assay using aptamer-functionalized silver nanocluster DNA probes

Area of Science:

• Biotechnology
• Analytical Chemistry
• Nanotechnology

Background:

• Developing sensitive and specific protein detection assays is crucial for diagnostics and research.
• Existing methods often require complex procedures like washing or separation steps.
• Silver nanoclusters (Ag NCs) offer unique fluorescence properties for biosensing applications.

Discussion:

• This study introduces a binding-induced fluorescence turn-on assay utilizing aptamers and guanine-rich DNA sequences.
• The assay leverages affinity binding to trigger DNA hybridization and subsequent fluorescence enhancement of Ag NCs.
• The method was successfully demonstrated for human alpha-thrombin detection with high sensitivity.

Key Insights:

• The assay achieves a low detection limit of 1 nM for human alpha-thrombin.
• A broad linear dynamic range of 5 nM-2 μM was established for protein quantification.
• The homogeneous assay format simplifies the detection process by eliminating washing and separation steps.

Outlook:

• The described principle can be adapted for detecting other target molecules by designing specific aptamer probes.
• This versatile platform holds potential for developing point-of-care diagnostic tools.
• Further research can explore the integration of this assay into microfluidic devices for enhanced throughput.