SmallTalks "Formulated fluorescent RNA studied with spectroscopy and scattering techniques"

Abstract 

RNA has emerged as a promising biomolecule for treating diseases currently lacking effective treatment. However, its poor stability and low bioavailability necessitates advanced delivery systems, such as lipid nanoparticles (LNPs). RNA therapeutics and their delivery vehicles are often studied using fluorescence-based techniques, typically by labelling the RNA with conventional bulky fluorophores like cyanine-5 (Cy5), which often perturb the natural behaviour of RNA. To address this problem, we have developed minimally perturbing fluorescent base analogues (FBAs), such as tCo, which can be incorporated directly into RNA and replace the natural bases. In this study, we investigate how and if the fluorescence labelling of RNA alters LNP structures by formulating RNA labelled with tCo or Cy5 and compare it to unlabelled RNA, using small angle X-ray and neutron scattering (SAXS and SANS). We also employ absorption spectroscopy to further investigate label-dependent RNA interactions.