2017 Bio-inspired peptide decorated dendrimers for a robust antibacterial coating on hydroxyapatite

Authors: Yaping Gou, Xiao Yang, Libang He, Xinyuan Xu, Yanpeng Liu, Yuebo Liu, Yuan Gao, Qin Huang, Kunneng Liang, Chunmei Ding, Jiyao Li, Changsheng Zhao and Jianshu Li.

Journal: Polym. Chem., 2017,8, 4264-4279  DOI: 10.1039/C7PY00811B

College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, China
State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China


Bacterial colonization on implanted biomaterials remains a clinically significant problem. In order to achieve relatively long-term antibacterial activity and reduce the incidence of infections associated with the use of biomaterials, a salivary statherin protein (SSP) inspired poly(amidoamine) dendrimer (SSP-PAMAM-NH2) was synthesized and characterized. PAMAM-NH2 has numerous peripheral amino groups, and thus possesses effective antibacterial activity. The SSP bio-inspired peptide sequence DDDEEKC was conjugated to PAMAM-NH2 since it has a strong capability of adsorbing on hydroxyapatite (HA). Moreover, SSP-PAMAM-NH2 is a zwitterionic polymer possessing cationic amino groups and anionic carboxylic groups, thus it can form aggregates by intermolecular electrostatic interactions, thereby promoting its adsorption on HA. Adsorption tests by ATR-IR, UV, QCM-D, and CLSM, all indicated that SSP-PAMAM-NH2 can tightly adsorb on the HA surface. We found that even after being incubated in PBS for 4 weeks, the SSP-PAMAM-NH2 treated HA disks still retained stable antibacterial activity, while the inhibitory impact of PAMAM-NH2 treated disks had disappeared. Animal experiments also demonstrated that SSP-PAMAM-NH2 could significantly reduce infection of HA implanted into the medullary cavity of rats.