摘要
生物黏液在生命活动过程中起着重要的调控作用,然而由于缺少合适的观测手段,目前对于天然状态下生物黏液功能界面超微结构的认知还很不足.原子力显微镜(atomic force microscopy,AFM)的出现为原位研究生物材料的结构和特性提供了新的强大工具,但现有的研究主要在空气环境下进行观测,研究结果难以完全反映溶液状态下的生物材料结构.本文以食虫植物茅膏菜分泌的黏液为研究对象,利用AFM直接在液相环境下实现了对生物黏液纳米结构的高分辨率成像及分析.分别将茅膏菜黏液平铺至载玻片和云母表面,在溶液环境下的AFM成像结果显示茅膏菜黏液中含有大量纳米颗粒.作为对照,在空气中进行的AFM成像结果显示干燥后的茅膏菜黏液中含有大量纳米纤维结构,表明了茅膏菜黏液在空气环境下与溶液环境下的结构差异.进一步利用AFM多参数成像方法对溶液环境下茅膏菜黏液纳米颗粒和纳米纤维的机械特性进行了可视化表征并揭示了纳米颗粒和纳米纤维机械特性的显著差异.研究结果为生物黏液功能界面超微结构原位成像及机械特性研究提供了新的方法和思路,对于生物材料研究具有广泛的基础意义.
Mucus plays an important role in regulating biological activities.Accordingly,investigating the structures and properties of mucus can be beneficial for providing a better understanding of physiological and pathological changes.Due to a lack of adequate observation tools,the ultra-microstructures of native mucus functional interfaces are not yet fully understood.Atomic force microscopy(AFM)provides a novel and powerful tool for investigating the structures and properties of biomaterials in their native states.Nevertheless,to date,studies of biomaterials using AFM are commonly performed in air,which cannot faithfully reflect the structures of biomaterials in liquids.In this paper,by adopting the mucilage secreted by the carnivorous sundew plant as an example,high-resolution AFM imaging and analysis of mucous nanostructures in aqueous conditions were achieved.Sundew mucilage was coated onto the surface of a glass slide or mica,and the subsequent AFM imaging of the mucilage-coated substrates in pure water revealed that a large number of nanoparticles were contained in the sundew mucilage.In contrast,AFM imaging of sundew mucilagecoated substrates in air showed that dried mucilage contained a large number of nanofibers.This underscored the structural differences in sundew mucilage in the air and in a solution.Furthermore,AFM multiparametric imaging was employed to visually characterize the mechanical properties of sundew mucilage nanostructures in pure water and showed significant differences in the mechanics between nanoparticles and nanofibers.This study provides a novel approach for investigating the ultra-microstructures and mechanics of mucus’functional interfaces in their native states in situ,which has fundamental impacts on research focused on biomaterials.
作者
李密
席宁
刘连庆
LI Mi;XI Ning;LIU LianQing(State Key Laboratory of Robotics,Shenyang Institute of Automation,Chinese Academy of Sciences,Shenyang 110016,China;Institute for Robotics and Intelligent Manufacturing,Chinese Academy of Sciences,Shenyang 110169,China;University of Chinese Academy of Sciences,Beijing 100049,China;Department of Industrial and Manufacturing Systems Engineering,The University of Hong Kong,Hong Kong 999077,China)
出处
《中国科学：技术科学》
EI
CSCD
北大核心
2021年第5期543-553,共11页
Scientia Sinica(Technologica)
基金
国家自然科学基金(批准号:61922081,61873258,U1613220,91748212)
中国科学院前沿科学重点研究计划(编号:ZDBS-LY-JSC043)
中国科学院青年创新促进会(编号:2017243)
辽宁省“兴辽英才计划”(编号:XLYC1907072)资助项目。
