Yancheva Elena, Paneva Dilyana, Maximova Vera, Mespouille Laetitia, Dubois Philippe, Manolova Nevena, Rashkov Iliya
Laboratory of Bioactive Polymers, Institute of Polymers, Bulgarian Academy of Sciences, Acad. G. Bonchev Street Bl. 103A, 1113 Sofia, Bulgaria.
Biomacromolecules. 2007 Mar;8(3):976-84. doi: 10.1021/bm061029j. Epub 2007 Feb 22.
Novel polyelectrolyte complexes (PECs) between N-carboxyethylchitosan (CECh) and well-defined (quaternized) poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA) have been obtained. The modification of chitosan into CECh allows the preparation of PECs in a pH range in which chitosan cannot form complexes. The CECh/PDMAEMA complex is formed in a narrow pH range around 7. The quaternization of the tertiary amino groups of PDMAEMA enables complex formation with CECh both in neutral and in alkaline medium. Cross-linked CECh is also capable of forming complexes with (quaternized) PDMAEMA. The antibacterial activity of (cross-linked) CECh, (quaternized) PDMAEMA, and their complexes against Escherichia coli has been evaluated. In contrast to (quaternized) PDMAEMA, (cross-linked) CECh exhibits no antibacterial activity. The complex formation between cross-linked CECh and (quaternized) PDMAEMA results in a loss of the inherent antibacterial activity of the latter in neutral medium. In acidic medium, the complexes exhibit strong antibacterial activity due to complex disintegration and release of (quaternized) PDMAEMA.
已获得N-羧乙基壳聚糖（CECh）与结构明确的（季铵化）聚甲基丙烯酸2-（二甲氨基）乙酯（PDMAEMA）之间的新型聚电解质复合物（PEC）。将壳聚糖改性为CECh可在壳聚糖无法形成复合物的pH范围内制备PEC。CECh/PDMAEMA复合物在pH约为7的狭窄范围内形成。PDMAEMA叔氨基的季铵化使得其在中性和碱性介质中均能与CECh形成复合物。交联的CECh也能够与（季铵化）PDMAEMA形成复合物。已评估了（交联）CECh、（季铵化）PDMAEMA及其复合物对大肠杆菌的抗菌活性。与（季铵化）PDMAEMA不同，（交联）CECh没有抗菌活性。交联CECh与（季铵化）PDMAEMA之间形成复合物导致后者在中性介质中丧失其固有的抗菌活性。在酸性介质中，由于复合物分解并释放出（季铵化）PDMAEMA，则复合物表现出较强的抗菌活性。
