첨부 '1' |
---|
author | Sungnam Park |
---|---|
journal | Phys. Chem. Chem. Phys., 2014, 16, 21747-21754 |
Homepage | http://femtolaser.korea.ac.kr/ |
Dynamics of water in bulk and ionic hydration shells in aqueous ionic solutions are different because of the local environments. However, direct measurements of the dynamics of water in ionic hydration shells apart from those of bulk water are quite challenging experimentally because of poor spectral distinction between water molecules in bulk and ionic hydration shells. Interestingly, the hydroxyl stretch band in the FTIR spectrum of aqueous NaPF6 solution can be resolved into contributions from three distinct subsets of water: (1) water molecules hydrogen-bonded to other water (i.e. bulk water), (2) water molecules in the hydration shells of Na+ ions (i.e. cationic hydration shell), and (3) water molecules hydrogen-bonded to PF6
ions (i.e. anionic hydration shell). Such spectral features allowed us to study the individual dynamics of water in different subsets in aqueous NaPF6 solution. IR pump–probe spectroscopy was used to measure vibrational population relaxation, P(t), and orientational anisotropy decay, r(t), of water in different subsets. The vibrational lifetimes of water in cationic and anionic hydration shells in aqueous 5.0 M NaPF6 solution were directly determined and found to be independent of temperature up to 50 1C. Orientational anisotropy decay of water in ionic hydration shells was observed to be much slower than in bulk. r(t) became faster with increasing temperature, as predicted by the Debye–Stokes–Einstein equation. The activation energies for water orientation in different subsets were measured and found not to differ greatly in cationic and anionic hydration shells. These experiments allowed us to study the dynamics of water in bulk and ionic hydration shells in aqueous NaPF6 solutions in more detail.

http://pubs.rsc.org/en/Content/ArticleLanding/2014/CP/c4cp02823f#!divAbstract
Prev Enhanced NIR Radiation-Triggered Hyperthermia by Mitochondrial Targeting
Enhanced NIR Radiation-Triggered Hyperthermia by Mitochondrial Targeting
2015.03.05by 관리자
Diamine-functionalized metal–organic framework: exceptionally... Next
Diamine-functionalized metal–organic framework: exceptionally...
2015.01.05by

-
Temperature-dependent dynamics of water in aqueous NaPF6 solution
Dynamics of water in bulk and ionic hydration shells in aqueous ionic solutions are different because of the local environments. However, direct measurements of the dynamics of water in ionic hydration shells apart from those of bulk water a... -
Diamine-functionalized metal–organic framework: exceptionally high CO2 capacities from ambient air and flue gas, ultrafast CO2 uptake rate, and adsorption mechanism
A framework en-Mg2(dobpdc) (1-en; en = ethylenediamine) functionalized with the primary amine en was prepared via postmodification. From synchrotron PXRD data, it is revealed that the cell parameters change upon grafting of en and CO2 uptake... -
pH-Dependent Proton Conducting Behavior in a Metal–Organic Framework Material
A porous metal–organic framework (MOF), [Ni2(dobdc)(H2O)2]⋅6 H2O (Ni2(dobdc) or Ni-MOF-74; dobdc4−=2,5-dioxido-1,4-benzenedicarboxylate) with hexagonal channels was synthesized using a microwave-assisted solvothermal reaction. Soaking Ni2(do... -
Template-Guided Solution-Shearing Method for Enhanced Charge Carrier Mobility in Diketopyrrolopyrrole-Based Polymer Field-Effect Transistors
Template-guided solution-shearing (TGSS) is used to fabricate field-effect transistors (FETs) composed of micropatterned prisms as active channels. The prisms comprise highly crystalline PTDPP-DTTE, in which diketopyrrolopyrrole (DPP) is fla... -
Mitochondrial Induced and Self-Monitored Intrinsic Apoptosis by Antitumor Theranostic Prodrug: In Vivo Imaging and Precise Cancer Treatment
Activation of apoptosis, the cell death machinery, in tumor cells by organelle-specific delivery of antitumor theranostic agent is the utmost challenge in cancer therapy. Herein, we developed a highly efficient mitochondria-targeting antitum... -
Two-Color Probe to Monitor a Wide Range of pH Values in Cells
Abstract High-tech pH paper : A “chameleon” pH probe composed of rhodamine (red, see scheme) and fluorescein (green) units emits at wavelengths of 580 nm and 512 nm, where the intensities show a contrary response to pH changes. Confocal micr... -
A Self-Calibrating Bipartite Viscosity Sensor for Mitochondria
Abstract High-tech pH paper : A self-calibrating bipartite viscosity sensor 1 for cellular mitochondria, composed of coumarin and boron-dipyrromethene (BODIPY) with a rigid phenyl spacer and a mitochondria-targeting unit, was synthesized. Th... -
Folate-Based Near-Infrared Fluorescent Theranostic Gemcitabine Delivery
Abstract A series of heptamethine cyanine (1−3) derivatives bearing a carbamate ethyl disulfide group and gemcitabine, an anticancer drug, have been newly synthesized. Their disulfide bonds are readily cleaved by various thiols including glu... -
An Activatable Theranostic for Targeted Cancer Therapy and Imaging
Abstract A new theranostic strategy is described. It is based on the use of an “all in one” prodrug, namely the biotinylated piperazine-rhodol conjugate 4 a. This conjugate, which incorporates the anticancer drug SN-38, undergoes self-immola... -
Toward a Chemical Marker for Inflammatory Disease: A Fluorescent Probe for Membrane-Localized
Abstract Thioredoxin (Trx) is a redox-active protein that plays a key role in mitigating the effects of oxidative stress. The secretion of Trx on the plasma membrane has been suggested as a distinctive feature of inflammation. However, selec...