Plasmonic Metallic Carbon Nanotube Assemblies Enhancing Raman Optical Activity of DNA for Ultra-Sensitive Detection of KRAS-Gene Point Mutations

Abstract

Highly sensitive methods of chiral Raman optics that allow to record conformational dynamics of deoxyribonucleic acid (DNA) molecules are promising for discrimination of somatic point mutations in the genome of colorectal cancer. The results of the sequencing are important for the correct drug prescription. However, it is challenging due to very low signal intensity of Raman optical activity of DNA. We offer a novel KRAS gene sequencing method which is based on the dependence of Raman band enhancement by plasmonic carbon nanotube assemblies on the DNA helicoidality degree and which registers the change of the DNA Raman optical activity due to formation of a homoduplex between complementary probe and target DNAs. We demonstrate that such a technology is very sensitive one when studying the allele single-nucleotide polymorphism of tumor genome.