Ricerc@Sapienza

Ten new heterodimers were synthesized in different stoichiometry to explore the role exerted by potential proton-transfer reactions in the supramolecular structures of A-B cocrystals formed by 5-haloderivatives of uracil (halogen = F, Cl, Br, I; coformer A) coupled with aminoazines as 2-aminoadenine simulants (melamine, 2,4,6-triaminopyrimidine, 2,6-diaminopyridine; coformer B) for pyrimidine nucleobase recognition.

To date, despite the crucial role played by cytosine, uracil, and thymine in the DNA/RNA replication process, no examples showing isomorphic and isostructural behavior among binary co-crystals of natural or modified pyrimidine nucleobases have been so far reported in the literature.

Fluorescence resonance energy transfer (FRET) system based on functionalized CdTe-guanine and AuNPs-cytosine bioconjugates for the model nucleobase - guanine detection was developed. Thioglycolic acid coated cadmium telluride quantum dots (QDs) conjugated with guanine and sodium 3-mercapto-1-propanesulfonate stabilized gold nanoparticles (AuNPs) capped by cytosine were obtained and fully characterized. Successful formation of the materials was confirmed by UV–Vis, fluorescence and FTIR spectroscopies. Composition of the conjugates was also characterized with elemental analysis and XPS.