A general method was developed for promoting peptide assembly and protein polymerization to form nanoscale patterns on various surfaces with an atomic force microscope(AFM) operated in a liquid. By scanning solid surf...A general method was developed for promoting peptide assembly and protein polymerization to form nanoscale patterns on various surfaces with an atomic force microscope(AFM) operated in a liquid. By scanning solid surfaces with an AFM tip, we showed that peptide monomers assemble at a higher rate in the tip-scanned area compared to other regions. The promotion is attributed to the mechanical force applied by the scanning tip. This kind of mechanical-force-promoted assembly was also observed with different peptides on various substrates. The force promoting peptide assembly provides a simple and practical solution for preparing and building peptide and protein architectures for future nanodevices.展开更多
Horseradish peroxidase monolayer was assembled on the surface of PET-CO2 substrate. The reaction kinetics of HRP/PET film and H2O2 in micro reactor was studied using improved spectrophotometer. The relative activity ...Horseradish peroxidase monolayer was assembled on the surface of PET-CO2 substrate. The reaction kinetics of HRP/PET film and H2O2 in micro reactor was studied using improved spectrophotometer. The relative activity of self-assembly HRP/PET film still remains above 80% after storing for 150 days at 4℃. When applied to determination of H2O2 in sample, the recoveries of H2O2 are 96.5%~101.1%.展开更多
细胞内肌动蛋白(actin)通过与actin结合蛋白(actin binding proteins,ABPs)相互作用,形成以F-actin为基础多种ABPs参与装配的高度有序的超分子聚合结构,行使各种重要生理功能。在体外聚合条件下,不存在F-actin稳定剂时纯化的actin主要...细胞内肌动蛋白(actin)通过与actin结合蛋白(actin binding proteins,ABPs)相互作用,形成以F-actin为基础多种ABPs参与装配的高度有序的超分子聚合结构,行使各种重要生理功能。在体外聚合条件下,不存在F-actin稳定剂时纯化的actin主要通过自装配形成大尺度的聚集堆积结构;这种表观无序的结构体系由于被认为不具备细胞功能活性而受到忽视。利用激光原子力显微镜(atomic force microscope,AFM)和透射电子显微镜(transmission electron microscope,TEM)技术,对actin体外通过自装配过程形成的大尺度聚集结构进行了细致的观察和分析。研究发现,actin在体外通过自装配过程除了形成无序的蛋白堆积物之外,还能够聚合形成复杂的离散结构,包括树状分支的纤维丛、无规卷曲的纤维簇以及具有不同直径的长纤维等;这些大尺度纤维复合物明显不同于在ABPs或过量F-actin稳定剂参与下形成的由单根微丝和微丝束构成的聚合结构。表明无ABPs或F-actin稳定剂存在的情况下,体外聚合的F-actin在一定条件下可进一步聚集缠绕形成复杂的纤维结构或无序的蛋白堆积物。事实上,actin自装配过程反映了其固有的聚合热力学特性,深入探索将有助于理解ABPs在体内actin超分子聚合结构体系装配中的调控作用及其分子机制。展开更多
Changes of the surface adhesion forces during the formation of octadecyltrichlorosilane (OTS) self assembled monolayer on glass substrate surface was investigated by Atomic Force Microscope (AFM). The research showed ...Changes of the surface adhesion forces during the formation of octadecyltrichlorosilane (OTS) self assembled monolayer on glass substrate surface was investigated by Atomic Force Microscope (AFM). The research showed that as the reaction proceeded, the hydrophobicities and the adhesion forces of the sample surfaces increased gradually. Afer 15 min reaction, the glass surface was completely hydrophobic with an advancing contact angle of 105° and an inteifacial energy of55. 79 mJ m-2.展开更多
基金supported by the National Natural Science Foundation of China(No.11674344)the National Basic Research Program of China(973 program,No.2013CB932801)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(No.QYZDJ-SSW-SLH019-2)
文摘A general method was developed for promoting peptide assembly and protein polymerization to form nanoscale patterns on various surfaces with an atomic force microscope(AFM) operated in a liquid. By scanning solid surfaces with an AFM tip, we showed that peptide monomers assemble at a higher rate in the tip-scanned area compared to other regions. The promotion is attributed to the mechanical force applied by the scanning tip. This kind of mechanical-force-promoted assembly was also observed with different peptides on various substrates. The force promoting peptide assembly provides a simple and practical solution for preparing and building peptide and protein architectures for future nanodevices.
文摘Horseradish peroxidase monolayer was assembled on the surface of PET-CO2 substrate. The reaction kinetics of HRP/PET film and H2O2 in micro reactor was studied using improved spectrophotometer. The relative activity of self-assembly HRP/PET film still remains above 80% after storing for 150 days at 4℃. When applied to determination of H2O2 in sample, the recoveries of H2O2 are 96.5%~101.1%.
文摘细胞内肌动蛋白(actin)通过与actin结合蛋白(actin binding proteins,ABPs)相互作用,形成以F-actin为基础多种ABPs参与装配的高度有序的超分子聚合结构,行使各种重要生理功能。在体外聚合条件下,不存在F-actin稳定剂时纯化的actin主要通过自装配形成大尺度的聚集堆积结构;这种表观无序的结构体系由于被认为不具备细胞功能活性而受到忽视。利用激光原子力显微镜(atomic force microscope,AFM)和透射电子显微镜(transmission electron microscope,TEM)技术,对actin体外通过自装配过程形成的大尺度聚集结构进行了细致的观察和分析。研究发现,actin在体外通过自装配过程除了形成无序的蛋白堆积物之外,还能够聚合形成复杂的离散结构,包括树状分支的纤维丛、无规卷曲的纤维簇以及具有不同直径的长纤维等;这些大尺度纤维复合物明显不同于在ABPs或过量F-actin稳定剂参与下形成的由单根微丝和微丝束构成的聚合结构。表明无ABPs或F-actin稳定剂存在的情况下,体外聚合的F-actin在一定条件下可进一步聚集缠绕形成复杂的纤维结构或无序的蛋白堆积物。事实上,actin自装配过程反映了其固有的聚合热力学特性,深入探索将有助于理解ABPs在体内actin超分子聚合结构体系装配中的调控作用及其分子机制。
文摘Changes of the surface adhesion forces during the formation of octadecyltrichlorosilane (OTS) self assembled monolayer on glass substrate surface was investigated by Atomic Force Microscope (AFM). The research showed that as the reaction proceeded, the hydrophobicities and the adhesion forces of the sample surfaces increased gradually. Afer 15 min reaction, the glass surface was completely hydrophobic with an advancing contact angle of 105° and an inteifacial energy of55. 79 mJ m-2.
