Label-free nucleic acids detection based on DNA templated silver nanoclusters fluorescent probe

Area of Science:

• Biochemistry
• Molecular Biology
• Nanotechnology

Background:

• Accurate detection of human immunodeficiency virus type 1 (HIV-1) DNA is crucial for clinical diagnosis and monitoring.
• Existing methods for HIV-1 DNA detection may require complex procedures or lack sufficient sensitivity.
• Development of novel, sensitive, and selective biosensors for rapid HIV-1 DNA detection is an ongoing research area.

Purpose of the Study:

• To develop a label-free fluorescent method for the sensitive and selective detection of HIV-1 DNA.
• To utilize DNA-templated silver nanoclusters (DNA/Ag NCs) as a fluorescent probe for HIV-1 DNA detection.
• To evaluate the method's performance in biological matrices like cell lysate and human serum.

Main Methods:

• Design of a hairpin probe incorporating a target DNA recognition sequence and a guanine-rich sequence.
• Hybridization of the hairpin probe with target HIV-1 DNA, followed by Exo III-mediated hydrolysis to release the target DNA and guanine-rich sequence.
• Detection of the released guanine-rich sequence using a DNA/Ag NCs fluorescent probe, resulting in enhanced fluorescence.

Main Results:

• The developed method achieved a low detection limit of 2.9×10(-10) mol L(-1) for HIV-1 DNA.
• The assay demonstrated excellent selectivity, distinguishing target HIV-1 DNA from mismatched sequences.
• High recovery rates were observed when the method was applied to cell lysate and human serum samples.

Conclusions:

• The label-free fluorescent method based on DNA/Ag NCs is highly sensitive and selective for HIV-1 DNA detection.
• The method shows significant potential for application in the analysis of clinical biological samples.
• This approach offers a promising tool for the rapid and accurate diagnosis of HIV-1 infections.