Binding abilities of polyaminocyclodextrins: polarimetric investigations and biological assays

Abstract

Three polyaminocyclodextrin materials, obtained by direct reaction between heptakis(6-deoxy-6-iodo)-β-cyclodextrin and the proper linear polyamines, were investigated for their binding properties, in order to assess their potential applications in biological systems, such as vectors for simultaneous drug and gene cellular uptake or alternatively for the protection of macromolecules. In particular, we exploited polarimetry to test their interaction with some model p-nitroaniline derivatives, chosen as probe guests. The data obtained indicate that binding inside the host cavity is mainly affected by interplay between Coulomb interactions and conformational restraints. Moreover, simultaneous interaction of the cationic polyamine pendant bush at the primary rim was positively assessed. Insights on quantitative aspects of the interaction between our materials and polyanions were investigated by studying the binding with sodium alginate. Finally, the complexation abilities of the same materials towards polynucleotides were assessed by studying their interaction with the model plasmid pUC19. Our results positively highlight the ability of our materials to exploit both the cavity and the polycationic branches, thus functioning as bimodal ligands.

A Two-Component regulatory system with opposite effects on glycopeptide antibiotic biosynthesis and resistance

“…N. gerenzanensis chromosomal DNA was used as template to amplify dbv6 by PCR using the primers 5'-aaaaggatccaatgcgcgttctggtggtgga-3' and 5'-ttttaagctttcagatgcgatatccctcgc-3' (underlines indicate the BamHI and HindIII sites, respectively). The amplified fragment was digested with BamHI plus HindIII and ligated into the BamHI and HindIII sites of pRSETB, yielding pRSET-Dbv6, which was introduced into BL21(DE3)pLysS cells by heat shock treatment 40 . Plasmid pRSET-Dbv6 expresses the entire Dbv6 protein with a His6 tag at its N terminus under the control of the T7 promoter and the lac operator.…”

Water Dynamics at the Solid–Liquid Interface to Unveil the Textural Features of Synthetic Nanosponges

“…The previous results can be interestingly compared with the composition of NS1 and NS2, which contain 5.5 × 10 –4 and 6.8 × 10 –4 mol g –1 of βCD, respectively. In general, p -substituted nitrobenzene derivatives form in solution only 1:1 complexes both with native and chemically modified βCDs; − however, due to the smaller volume of these guests as compared to the host cavity, a simultaneous dynamic coinclusion of solvent molecules occurs . Moreover, evidence has been reported (2D-LFSE solid-state NMR) that, in the case of the inclusion of a p -nitroaniline derivative in a polyamino-cyclodextrin NS, the guest specifically occupies the cyclodextrin cavities and does not reside in the nanochannels .…”

Mononuclear Perfluoroalkyl-Heterocyclic Complexes of Pd(II): Synthesis, Structural Characterization and Antimicrobial Activity

“…The antimicrobial activity was calculated at least as a mean of three replicates. DNA binding activity of 10 mM of the complexes was evaluated by using electrophoretic mobility shift assays (EMSA) of 100 ng of pUC19 DNA plasmid as described elsewhere [ 38 ]. At the end of the electrophoresis, the gel was ethidium bromide stained and photographed.…”