The well defined core-shell polymer brush with poly(N-isopropylacrylamide) as shell was investigated by dynamic laser light scattering.Compared with the isolated three-dimensional chain,the grafted PNIPAM chains have ...The well defined core-shell polymer brush with poly(N-isopropylacrylamide) as shell was investigated by dynamic laser light scattering.Compared with the isolated three-dimensional chain,the grafted PNIPAM chains have a broader range in thickness change with a decrease in solvent quality due to the interchain interaction in spherical geometry.With the increasing of the molecule weight of the PNIPAM,the phase transition of grafted chain change from single transition to two stage transition.At T = 250C,the <L>shell can be scale to N as <L>shell∝N0.9±0.1.With increasing of the temperature,the exponential of scaling law of <L>shell and N decrease a little.However,the PNIPAM chains still expand with <L>shell ∝N0.76±0.10 due to the high grafted chain density.展开更多
Supramolecular binary vesicles were constructed by host-guest complex formation between p-sulfonatocalix[4]arene and three cationic gemini surfactants, which were identified by UV-vis, dynamic laser scattering, transm...Supramolecular binary vesicles were constructed by host-guest complex formation between p-sulfonatocalix[4]arene and three cationic gemini surfactants, which were identified by UV-vis, dynamic laser scattering, transmission electron microscopy, scanning electron microscopy, atomic force microscopy, and surface tension experiments. The critical aggregation concentration of gemini surfactants decreased pronouncedly by a factor of ca. 1000 owing to the complexation of p-sulfonato-calix[4]arene.展开更多
Our dynamic laser light scattering(LLS) study shows that the current widely used protocols of dissolving amyloidogenic protein/peptide do not really result in a true solution;namely,there always exist a trace amount o...Our dynamic laser light scattering(LLS) study shows that the current widely used protocols of dissolving amyloidogenic protein/peptide do not really result in a true solution;namely,there always exist a trace amount of interchain aggregates,which greatly affect the association kinetics,partially explaining why different kinetics were reported even for a solution with identical protein and solvent.Recently,using a combination of the conventional dissolution procedure and our newly developed ultra-filtration method,we have developed a novel protocol to prepare a true solution of amyloidogenic protein/peptide without any interchain aggregates.The resultant solutions remain in their monomeric state for at least one week,which is vitally important for further study of the very initial stage of the interchain association under the physiological conditions because more and more evidence suggests that it is those small oligomers rather than large fabric aggregates that are cytotoxic.In addition,this study shows that combining static and dynamic LLS can lead to more physical and microscopic information about the protein association instead of only the size distribution.展开更多
Reversible assembly and disassembly of rod-like large complex micelles have been achieved by applying photoswitching of supramolecular inclusion and exclusion of azobenzene-functionalized hyperbranched polyglycerol a...Reversible assembly and disassembly of rod-like large complex micelles have been achieved by applying photoswitching of supramolecular inclusion and exclusion of azobenzene-functionalized hyperbranched polyglycerol and α-cyclodextrin as driving force, promising a versatile system for self-assembly switched by light. Hydrogen-nuclear magnetic resonance (1H NMR) and Fourier transform infrared (FT-IR) spectroscopy were applied to characterize the azobenzene-functionalized hyperbranched polyglycerol. Atomic force microscopy (AFM), transmission electron microscopy (TEM) and dynamic laser light scattering (DLS) were employed to investigate and track the morphology of the rod-like large complex micelles before and after irradiation of UV light.展开更多
Our dynamic laser light scattering(LLS) study shows that the current widely used protocols of dissolving amyloidogenic protein/peptide do not really result in a true solution;namely,there always exist a trace amount o...Our dynamic laser light scattering(LLS) study shows that the current widely used protocols of dissolving amyloidogenic protein/peptide do not really result in a true solution;namely,there always exist a trace amount of interchain aggregates,which greatly affect the association kinetics,partially explaining why different kinetics were reported even for a solution with identical protein and solvent.Recently,using a combination of the conventional dissolution procedure and our newly developed ultra-filtration method,we have developed a novel protocol to prepare a true solution of amyloidogenic protein/peptide without any interchain aggregates.The resultant solutions remain in their monomeric state for at least one week,which is vitally important for further study of the very initial stage of the interchain association under the physiological conditions because more and more evidence suggests that it is those small oligomers rather than large fabric aggregates that are cytotoxic.In addition,this study shows that combining static and dynamic LLS can lead to more physical and microscopic information about the protein association instead of only the size distribution.展开更多
Sulfonatocalix[4]arene lowers the critical aggregation concentration of fluorocarbon surfactant pronouncedly by a factor of ca.100 to form binary amphiphilic aggregates on the basis of host-guest complexation,which wa...Sulfonatocalix[4]arene lowers the critical aggregation concentration of fluorocarbon surfactant pronouncedly by a factor of ca.100 to form binary amphiphilic aggregates on the basis of host-guest complexation,which was identified by1H NMR spectroscopy,fluorescence spectroscopy,optical transmittance spectroscopy,dynamic laser scattering,high-resolution transmission electron microscopy,scanning electron microscopy,and surface tension experiments.Moreover,the resulting aggregates can respond to external stimuli,including temperature and inclusion of competitor guest.Therefore,the present system may have potential applications in drug delivery systems.展开更多
基金We thank professor Fan Jin of University of Science and Technology of China provided idea and designed the experiments. This work was supported by the National Program on Key Basic Research Project (No.2012CB933802) and the National Natural Science Foundation of China (No.21274141, No.21104071).
文摘The well defined core-shell polymer brush with poly(N-isopropylacrylamide) as shell was investigated by dynamic laser light scattering.Compared with the isolated three-dimensional chain,the grafted PNIPAM chains have a broader range in thickness change with a decrease in solvent quality due to the interchain interaction in spherical geometry.With the increasing of the molecule weight of the PNIPAM,the phase transition of grafted chain change from single transition to two stage transition.At T = 250C,the <L>shell can be scale to N as <L>shell∝N0.9±0.1.With increasing of the temperature,the exponential of scaling law of <L>shell and N decrease a little.However,the PNIPAM chains still expand with <L>shell ∝N0.76±0.10 due to the high grafted chain density.
基金supported by the National Natural Science Foundation of China (20932004)the Prospective Basic Research Subject of China Petroleum (P07009)
文摘Supramolecular binary vesicles were constructed by host-guest complex formation between p-sulfonatocalix[4]arene and three cationic gemini surfactants, which were identified by UV-vis, dynamic laser scattering, transmission electron microscopy, scanning electron microscopy, atomic force microscopy, and surface tension experiments. The critical aggregation concentration of gemini surfactants decreased pronouncedly by a factor of ca. 1000 owing to the complexation of p-sulfonato-calix[4]arene.
基金support of the National Natural Science Foundation of China Project(20934005)the Hong Kong Special Administration Region Earmarked Project(CUHK4046/08P,2160365+1 种基金CUHK4039/08P,2160361 CUHK4042/09P,2160396)
文摘Our dynamic laser light scattering(LLS) study shows that the current widely used protocols of dissolving amyloidogenic protein/peptide do not really result in a true solution;namely,there always exist a trace amount of interchain aggregates,which greatly affect the association kinetics,partially explaining why different kinetics were reported even for a solution with identical protein and solvent.Recently,using a combination of the conventional dissolution procedure and our newly developed ultra-filtration method,we have developed a novel protocol to prepare a true solution of amyloidogenic protein/peptide without any interchain aggregates.The resultant solutions remain in their monomeric state for at least one week,which is vitally important for further study of the very initial stage of the interchain association under the physiological conditions because more and more evidence suggests that it is those small oligomers rather than large fabric aggregates that are cytotoxic.In addition,this study shows that combining static and dynamic LLS can lead to more physical and microscopic information about the protein association instead of only the size distribution.
基金supported by the National Natural Science Foundation of China (20974093)the National Basic Research Program of China (973 Program, 2007CB936004)+3 种基金Qianjiang Talent Foundation of Zhejiang Province (2010R10021)the Fundamental Research Funds for the Central Universities (2009QNA4040)Zhejiang Provincial Natural Science Foundation of China (R4110175)Research Fund for the Doctoral Program of Higher Education of China ( 20100101110049)
文摘Reversible assembly and disassembly of rod-like large complex micelles have been achieved by applying photoswitching of supramolecular inclusion and exclusion of azobenzene-functionalized hyperbranched polyglycerol and α-cyclodextrin as driving force, promising a versatile system for self-assembly switched by light. Hydrogen-nuclear magnetic resonance (1H NMR) and Fourier transform infrared (FT-IR) spectroscopy were applied to characterize the azobenzene-functionalized hyperbranched polyglycerol. Atomic force microscopy (AFM), transmission electron microscopy (TEM) and dynamic laser light scattering (DLS) were employed to investigate and track the morphology of the rod-like large complex micelles before and after irradiation of UV light.
文摘Our dynamic laser light scattering(LLS) study shows that the current widely used protocols of dissolving amyloidogenic protein/peptide do not really result in a true solution;namely,there always exist a trace amount of interchain aggregates,which greatly affect the association kinetics,partially explaining why different kinetics were reported even for a solution with identical protein and solvent.Recently,using a combination of the conventional dissolution procedure and our newly developed ultra-filtration method,we have developed a novel protocol to prepare a true solution of amyloidogenic protein/peptide without any interchain aggregates.The resultant solutions remain in their monomeric state for at least one week,which is vitally important for further study of the very initial stage of the interchain association under the physiological conditions because more and more evidence suggests that it is those small oligomers rather than large fabric aggregates that are cytotoxic.In addition,this study shows that combining static and dynamic LLS can lead to more physical and microscopic information about the protein association instead of only the size distribution.
基金supported by the National Basic Research Program of China(2011CB932502)the National Natural Science Foundation of China(91227107 and 21172119)
文摘Sulfonatocalix[4]arene lowers the critical aggregation concentration of fluorocarbon surfactant pronouncedly by a factor of ca.100 to form binary amphiphilic aggregates on the basis of host-guest complexation,which was identified by1H NMR spectroscopy,fluorescence spectroscopy,optical transmittance spectroscopy,dynamic laser scattering,high-resolution transmission electron microscopy,scanning electron microscopy,and surface tension experiments.Moreover,the resulting aggregates can respond to external stimuli,including temperature and inclusion of competitor guest.Therefore,the present system may have potential applications in drug delivery systems.