Detection of HPV-16 by a Simple and Cost-Effective DNA Probe: Polyadenine-Polythymine-Decorated Gold Nanoparticles (PolyA-PolyT@AuNPs).

Abstract

HPV-16 identification is crucial for point-of-care molecular diagnosis of cervical cancer. However, the diagnostic methods currently in use are unable to combine both high analytical performance and cost-efficient medical diagnosis. To circumvent this, we have developed a novel nanobiosensor for diagnosis of the HPV-16 L1 gene sequence through colorimetric methods. Using a unique conjugation technique of polyvalent DNA to gold nanoparticles (AuNPs), quickly synthesizing AuNPs synthesis in situ at the particular probe-polyadenine-polythymine (A₁₅-T₁₀) strands was developed. Transmission electron microscopy (TEM), dynamic light scattering (DLS), gel electrophoresis, UV-Vis spectroscopy, and visual detection demonstrate that the Poly(A)₁₅-(T)₁₀ strand can create separate anisotropic AuNPs so that a thick layer of DNA is functionalized on each AuNP, therefore generating polyvalent (p)DNA-AuNPs. Moreover, the hybridization test, UV-Vis spectroscopy, TEM, visual detection, and DLS results further confirmed the innovative sensing applicability, showing more excellent attractiveness of pDNA-AuNPs conjugation in diagnostics in biomedicine and particular sequence detection, such as double-stranded DNA (dsDNA) by employing probe-polyA-polyT extra-strands that are in harmony with the intended sequence. This sensor demonstrated good performance levels with a sensitivity of up to 1.9 nM for pUCm-T. Additionally, the sensor showed intense discrimination against actual clinically collected HPV-16 samples, consistent stability, and good repeatability.