CONICET | Buscador de Institutos y Recursos Humanos

P { margin-bottom: 0.08in; direction: ltr; color: rgb(0, 0, 0); text-align: left; widows: 2; orphans: 2; }P.western { font-family: "Times New Roman",serif; font-size: 12pt; }P.cjk { font-family: "WenQuanYi Zen Hei","Times New Roman"; font-size: 12pt; }P.ctl { font-family: "Lohit Devanagari","Times New Roman"; font-size: 12pt; }A:link { color: rgb(0, 0, 255); }A.western:link { }A.ctl:link { } A novel class of environmentally benign, non-toxic and recyclable materials based on vinylbenzyl thymine (VBT) and an ionically-charged vinylbenzyl triethylammonium chloride (VBA) monomers was studied. This compounds were bio-inspired in the nitrogen bases interactions that happened in DNA degenerative processes and their reversion possibility using specific enzymes from life organisms. The hydrophilic nature of VBA let us work without using organic solvents in the polymerization process. The technological applications of these polymers has became earlier than the necessary basic studies which could help to understand their behavior and improve their services. We present a study of the influence of the co-polymerization molar relationship VBT:VBA on the short distance structure adopted by the polymers chains. We carried out several Molecular Dynamics simulations of these polymers and also Circular Dichroism experiments. We run simulations of 32 monomers of VBT:VBA (1:1) and 35 monomers of VBT:VBA (1:4) in explicit water (SPC model). The polymer 1:1 showed 75 % of its monomers in helix conformation, while the 1:4 only showed 54 %. We detected thymine piling up between residues (i, i+4) and (i,i+5) in the former and latter polymer respectively. The number of residues in a helix turn was 3.6 and 4.0 for the stoichiometry 1:1 and 1:4 respectively. The helix structure of the polymer 1:4 was interrupted by longer unstructured segments than in the 1:1, showing also more undulations of its backbone. The former also showed a higher number of water molecules, solvent accessible surface and H bond numbers closed to it than the polymer 1:1, indicating that the unstructured segments (in 1:4 polymer) let enter more water close to it. In all cases we found at least one thymine piling up inside the helix segments, which could explain in part the helix stability. In summary, we can conclude that thymine piling up would be responsible (at least in part) of the helix structure of the polymer, helping to lower the SAS of the hydrophobic moiety. The lack of CD signal was in agreement with the simulation results.