Related Experiment Video
Updated: Jun 13, 2026
09:43
Interfacial Molecular-level Structures of Polymers and Biomacromolecules Revealed via Sum Frequency Generation Vibrational Spectroscopy
Published on: August 13, 2019
Hydration water/interfacial water in crystalline lens
1Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, Budapest, POB 49, H-1525, Hungary.
Experimental Eye Research
|April 24, 2010
Summary
Avian crystalline lens hydration was quantified using NMR and DSC. Results reveal interfacial water is crucial for protein activity and lens health, distinct from bulk water.
Area of Science:
- Biophysics
- Structural Biology
- Materials Science
Background:
- The avian crystalline lens's protein hydration is key to its transparency and function.
- Understanding protein-water interactions is vital for lens physiology and cataract formation.
Purpose of the Study:
- To quantitatively measure protein hydration in avian crystalline lenses.
- To characterize the protein-water interfacial region and its role in lens health and disease.
Main Methods:
- Wide-line (1)H NMR spectroscopy to measure signal intensity, spin-lattice, and spin-spin relaxation rates.
- Differential scanning calorimetry (DSC) for thermal analysis.
- Measurements conducted across a temperature range of -70°C to +45°C.
Main Results:
- A water mobility transition observed at -60°C indicates melting of interfacial/hydrate water.
- The mobile water fraction (0.4 g/g protein) is essential for protein activity.
- Interfacial water exhibits distinct relaxation dynamics and higher specific heat than bulk water, suggesting strong thermodynamic coupling with the protein matrix.
Conclusions:
- Avian crystalline lens protein and its hydration layer function as a single, interconnected thermodynamic phase.
- These findings are critical for understanding lens physiology and the development of cataracts.
Related Concept Videos
03:13Intermolecular Forces
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen bonds, and dispersion...
02:28Intermolecular Forces in Solutions
The formation of a solution is an example of a spontaneous process, a process that occurs under specified conditions without energy from some external source.
When the strengths of the intermolecular forces of attraction between solute and solvent species in a solution are no different than those present in the separated components, the solution is formed with no accompanying energy change. Such a solution is called an ideal solution. A mixture of ideal gases (or gases such as helium and argon,...
When the strengths of the intermolecular forces of attraction between solute and solvent species in a solution are no different than those present in the separated components, the solution is formed with no accompanying energy change. Such a solution is called an ideal solution. A mixture of ideal gases (or gases such as helium and argon,...
02:42Aqueous Solutions and Heats of Hydration
Water and other polar molecules are attracted to ions. The electrostatic attraction between an ion and a molecule with a dipole is called an ion-dipole attraction. These attractions play an important role in the dissolution of ionic compounds in water.
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
01:12Solvents
A solvent is a substance, most often a liquid, that can dissolve other substances. Here, the substance being dissolved is called a solute. When a solvent and a solute combine, they form a solution - a homogenous mixture of both the solvent and the solute. Water is a universal biological solvent. Its polar structure allows it to dissolve many other polar compounds. The ability of water to dissolve is governed by a balance between water molecules binding to each other and binding to the solute.
A...
A...
01:16Solubility Equilibria: Ionic Product of Water
Pure water is a weak electrolyte; only a small amount ionizes into hydrogen and hydroxide ions. At any given temperature, the concentration of undissociated water is almost constant, so the ionic product of water is the product of the hydrogen and hydroxide ion concentrations, denoted as Kw. The square root of Kw gives the individual ion concentrations.
The ionic product of water varies with temperature, and its value is 1.0 x 10−14 at standard experimental conditions. Per Le Chatelier's...
The ionic product of water varies with temperature, and its value is 1.0 x 10−14 at standard experimental conditions. Per Le Chatelier's...
01:07Cohesion
Cohesion is the attraction between molecules of the same type, such as water molecules. Water molecules have an overall neutral charge but are polar molecule. An oxygen atom in one water molecule has a partial negative charge that can bind to a hydrogen atom with a partial positive charge in a second water molecule, forming a hydrogen bond. Each water molecule can form up to four hydrogen bonds with other water molecules. Hydrogen bonds are responsible for water's cohesive nature.
On a surface,...
On a surface,...