DNA-Silver Nanocluster Binary Probes for Ratiometric Fluorescent Detection of HPV-related DNA

Herein, we described a ratiometric strategy based on “chameleon” DNA-silver nano-clusters(DNA-AgNCs) fluorescent binary probes. The strategy was applied to detect high-risk human papillomavirus(HPV) DNA sequences, HPV-16. First, DNA-AgNCs were synthesized by a simple reduction method. The obtained nanoprobes showed typical yellow and red fluorescence of AgNCs. Upon the addition of HPV-16 DNA, the yellow fluorescence of AgNCs was reduced greatly, whereas the red fluorescence of AgNCs was increased. The concentration of HPV-16 DNA in the samples was characterized by the ratio of fluorescence intensity at 570 and 630 nm. The ratiometric nanoprobes showed good selectivity for HPV-16 DNA, and the detection limit was 2 nmol/L. In addition, the practical applicability of this strategy was demonstrated by analysing the HPV-16 DNA in human serum, illustrating its potential promise for clinical diagnosis.