The total helix content has been estimated by circular dichroism measurements for sodium poly(Lglutamate)/ poly(L-lysine) hydrobromide (PLGNa/PLLHBr) mixed systems in aqueous alcohols. The polyion complexes were soluble in the mixed solvents, on account of the rather low total polymer concentration (6.2 ? 10 -4 (base) mol 1-1), except when a polymer mixing ratio of 1:1 equivalents was used. It has been observed that the total helix content significantly decreases with polymer mixing, when compared to that observed in single polymer systems, while by the addition of C104, or a short-chain PLGNa, both of which stabilize the helix conformation of PLL, the respective helix conformations are almost completely retained. These experimental findings, together with those concerning the dependence of the helix content on the alcohol species, are discussed, and possible structures for the polyion complexes are proposed.
Посилання на статтю:
Helix formation of poly(L-glutamic acid) and poly(L-lysine) in the polyion complex prepared in aqueous alcohol solutions / Mitsuru Satoh*, Tetsuya Hirose and Jiro Komiyarna // Polymer. – 1994. – Vol 35. – P. 3492-3498.