Genotyping simplified: rationally designed antisense oligonucleotide-mediated PCR amplification-free colorimetric sensing of viral RNA in HCV genotypes 1 and 3.

Molecular diagnosis of viral genotyping devoid of polymerase chain reaction (PCR) amplification in clinical cohorts has hitherto been challenging. Here we present a simplified molecular diagnostic strategy for direct genotyping of hepatitis C virus (HCV) 1 and 3 (prevalent worldwide) using a combination of rationally designed genotype-specific antisense oligonucleotides (ASOs) and plasmonic gold nanoparticles. The ASOs specific to genotypes 1 and 3 have been designed from the nonstructural region 5A (NS5A) of the viral genome using the ClustalW multiple sequence alignment tool.

Naked-eye colorimetric detection of HCV RNA mediated by a 5' UTR-targeted antisense oligonucleotide and plasmonic gold nanoparticles.

The increasing incidence of hepatitis C viral (HCV) infection worldwide is a major concern for causing liver cirrhosis and hepatocellular carcinoma, leading to increased morbidity and mortality. Currently, the prevalence of HCV infection is estimated to be in the range of ∼3%. According to the World Health Organization, antiviral drugs can cure more than 95% of the HCV infected cases, if timely diagnosis and treatment are provided.

Effects of free patchy ends in ssDNA and dsDNA on gold nanoparticles in a colorimetric gene sensor for Hepatitis C virus RNA.

The presence or absence and nature of the free patchy ends in DNA sequences has a decisive effect on the performance of colorimetric sensors based on the use of gold nanoparticles (Au NPs). The authors have designed two unmodified gene probes (probe 1: a 19-mer; probe 2: an 18-mer). They are complementary to either half of a 37-mer target derived from the conserved region of Hepatitis C Virus (HCV) RNA.