MH, NR, and GS conceived and designed this study. NR and GS also supervised the project, participated in the discussion on the results, and helped improve the manuscript. All authors read and improved the final manuscript.”
“Background Detection of DNA sequences through hybridization between two complementary single strands is a basic method that is very often exploited at the DNA biosensor development [1]. Now new opportunities have appeared in this route due to synthesis of new nanomaterials which are intensively applied

as the scaffold, transducer, or sensitive detectors. In particular, carbon nanotubes have attracted keen interest of biosensor researchers [2]. GSK1120212 datasheet It was found that single-stranded nucleic acid (ssDNA) binds to the single-walled carbon nanotube (SWNT), forming a stable soluble hybrid in water [3]. In spite of the essential difference in CRM1 inhibitor structures of nanotubes and the biopolymer, ssDNA wraps tightly around the nanotube in water when hydrophobic nitrogen bases are adsorbed onto the nanotube surface via π-π stacking, while the hydrophilic sugar-phosphate

backbone is pointed towards water [3, 4]. The hybridization of nucleic acids on SWNT is extensively investigated [5–22], having in sight the development of DNA-hybridized biosensors on the base of nanotubes. Nevertheless, in spite of 10-year investigations in this field, some questions arise upon the study of DNA hybridization on the nanotube especially when the probe polymer was adsorbed to the tube surface directly. One of the keen questions is the effect of DNA interaction with the tube surface on the polymer hybridization. Effective Protein kinase N1 detection of hybridization of two complementary DNA strands on the nanotube surface was demonstrated in [5–7]; however, in other measurements [12,

14, 17], it was indicated that SWNT hampers effective hybridization of two polymers because of the strong interaction with the nanotube surface, which prevents the necessary conformational mobility of the polymer to be hybridized. Some researchers suppose that the double-stranded DNA (dsDNA) is desorbed from the sidewall of SWNT after hybridization [14, 18–22]. Thus, up to now, the full picture of the biopolymer hybridization on SWNT surface is still unclear, and in some cases, the conclusions are controversial. To clarify this ambiguity, an additional study is required. In this work, we focus our research on the hybridization of polyribocytidylic acid (poly(rC)) adsorbed to the carbon nanotube surface with polyriboinosinic acid (poly(rI)) free in solution.