[凝態中心演講] Lecture on March 7, 14:20-15:20, Prof. Chung-Yuan Mou 牟中原教授 (CCMS/Physics Building R104)
消息來源：化學系辦公室
截止日期：2017-03-03
Date：2017/03/07（Tuesday）
Time：14:20 -15:20
Location：CCMS/Physics Building R104
Speaker：Prof. Chung-Yuan Mou, Department of Chemistry, National Taiwan University.
Title：Nano-Confined Water
Abstract:
Water under nano-confinement is different from normal water. It is relevant to life and geoscience because much of the hydration phenomenon in nature occurs in narrowly confined water. Studying confined water will help one to understand the physicochemical effect of water and its interaction with solutes in crowded environment. Mesoporous silica materials with uniform pore size will be the confining media in our study. By using neutron and X-ray scattering techniques, we studied the density and diffusion of water under nanoconfinement. By confining solutes, solubility of a hydrophobic molecule such as Xe in water under nanoconfinement will impact several related problems, (a) solubility of methane in water within nanopores of rock under fracking condition, (b) understanding how hydrophobic effect would be changed in confined water, (c) how protein hydration would change under confinement.
We studied hydration behavior of Xe in water confined in mesoporous silica using Xe-NMR chemical shifts. Temperature change of the signal allows us to determine the enthalpy of hydration. It was found that in pore confined water, the hydration of Xe is more energetically favorable than in bulk water. The increased solubility of Xe in nanopore is in the same trend with computer simulation results of confined methane.
Next, we employed mesoporous silica of matching pore sizes to confine lysozyme in order to mimic enzyme in a crowded environment. The stability and activity of lysozyme immobilized in mesoporous silica nanoparticle (MSN) of various pore sizes were studied and correlated to spectroscopic data of the immobilized enzyme. It was found that the activity of the lysozyme immobilized in the 5.6 nm mesopores of MSNs was higher than those of native enzymes. The enhanced activity was attributed to subtle change in hydration of lysozyme due to increased stability of hydrophobic solvation.
Time：14:20 -15:20
Location：CCMS/Physics Building R104
Speaker：Prof. Chung-Yuan Mou, Department of Chemistry, National Taiwan University.
Title：Nano-Confined Water
Abstract:
Water under nano-confinement is different from normal water. It is relevant to life and geoscience because much of the hydration phenomenon in nature occurs in narrowly confined water. Studying confined water will help one to understand the physicochemical effect of water and its interaction with solutes in crowded environment. Mesoporous silica materials with uniform pore size will be the confining media in our study. By using neutron and X-ray scattering techniques, we studied the density and diffusion of water under nanoconfinement. By confining solutes, solubility of a hydrophobic molecule such as Xe in water under nanoconfinement will impact several related problems, (a) solubility of methane in water within nanopores of rock under fracking condition, (b) understanding how hydrophobic effect would be changed in confined water, (c) how protein hydration would change under confinement.
We studied hydration behavior of Xe in water confined in mesoporous silica using Xe-NMR chemical shifts. Temperature change of the signal allows us to determine the enthalpy of hydration. It was found that in pore confined water, the hydration of Xe is more energetically favorable than in bulk water. The increased solubility of Xe in nanopore is in the same trend with computer simulation results of confined methane.
Next, we employed mesoporous silica of matching pore sizes to confine lysozyme in order to mimic enzyme in a crowded environment. The stability and activity of lysozyme immobilized in mesoporous silica nanoparticle (MSN) of various pore sizes were studied and correlated to spectroscopic data of the immobilized enzyme. It was found that the activity of the lysozyme immobilized in the 5.6 nm mesopores of MSNs was higher than those of native enzymes. The enhanced activity was attributed to subtle change in hydration of lysozyme due to increased stability of hydrophobic solvation.