生物医用纳米颗粒表面的两性离子化设计

Zwitterions in Surface Engineering of Biomedical Nanoparticles

生物医用纳米颗粒的表面设计对维持纳米颗粒稳定性和抑制蛋白质非特异性吸附从而实现体内长效循环等具有重要意义。具有细胞膜仿生结构的两性离子界面能通过离子静电作用形成高效水合层,不仅可有效增强纳米颗粒的稳定性和抗免疫清除能力,通过提高体内循环时间增强其"被动"靶向能力,而且当与环境响应性或生物活性分子复合后,还可有效实现纳米颗粒的"主动"靶向功能,因此"两性离子化"已经发展为纳米颗粒表面设计的新策略。本文主要概述了两性离子材料在生物医用纳米表面设计中的应用进展,包括小分子和聚合物两性离子对无机纳米颗粒的表面修饰、聚合物两性离子组装体用于抗肿瘤药物传递等,同时也介绍了混合电荷材料的一些特殊性质和应用。

Surface engineering of biomedical nanoparticles is of great importance to maintain nano-stability,resist nonspecific biomolecular adsorption so as to enhance in vivo circulation time. Cell membrane mimicking zwitterions can form superhydrophilic antifouling surface which helps to maintain colloidal stability and resist immune elimination via electrostatically induced hydration. The stealthy surface prolongs the blood circulation time to reach ＂passive targeting ＂,further ＂active targeting ＂is also available if combined with stimuli-responsive or bioactive molecules. Hence ＂zwitteration＂has been developed as a new surface engineering strategy of biomedical nanoparticles. This review mainly talks about surface engineering of inorganic nanoparticles w ith small molecular and polymeric zwitterions,zwitterionic polymeric assemblies as drug delivery system and zwitterionic polymeric prodrugs. Introduction of special properities and applications of mixed-charge materials is also involved.