Related Experiment Video
Updated: Jun 6, 2026
09:49
Sedimentation Equilibrium of a Small Oligomer-forming Membrane Protein: Effect of Histidine Protonation on Pentameric Stability
Published on: April 2, 2015
Beyond the second virial coefficient: Sedimentation equilibrium in highly non-ideal solutions
1Chemical and Physical Biology Programme, Centro de Investigaciones Biológicas, CSIC, Madrid, Spain. grivas@cib.csic.es
Methods (San Diego, Calif.)
|November 30, 2010
Summary
This study summarizes sedimentation equilibrium (SE) theory and techniques for analyzing interacting solutes. Non-ideal tracer sedimentation equilibrium (NITSE) is detailed for characterizing molecular interactions in complex mixtures.
Area of Science:
- Biophysical Chemistry
- Macromolecular Science
- Analytical Biochemistry
Background:
- Sedimentation equilibrium (SE) is a powerful technique for studying macromolecular solutions.
- Understanding solute interactions is crucial for fields like protein science and polymer chemistry.
- Existing SE methods may have limitations with complex or concentrated systems.
Purpose of the Study:
- To provide a comprehensive overview of sedimentation equilibrium theory and practical data acquisition.
- To introduce and detail the non-ideal tracer sedimentation equilibrium (NITSE) method.
- To review experimental applications of SE and NITSE for characterizing intermolecular interactions.
Main Methods:
- Summarizing the general theory of sedimentation equilibrium for interacting solutes.
- Describing practical techniques for obtaining reliable SE data.
- Detailing the methodology of non-ideal tracer sedimentation equilibrium (NITSE).
Main Results:
- SE theory is applicable to interacting solutes at various concentrations.
- NITSE enables the detection and quantification of intermolecular interactions.
- Experimental studies demonstrate the utility of SE and NITSE in protein and polymer solutions.
Conclusions:
- Sedimentation equilibrium provides a robust framework for analyzing macromolecular solutions.
- NITSE is an effective method for probing molecular interactions in complex mixtures.
- These techniques are valuable for advancing our understanding of solution behavior in biophysical and polymer systems.
More Related Videos
10:28Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids
Published on: January 3, 2014
11:51Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
Related Concept Videos
01:29Nonideal Two-Component Liquid Solutions
Nonideal liquid solutions, also known as real solutions, do not strictly follow Raoult's law. Raoult's law is a rule of thumb in physical chemistry. However, not all mixtures adhere to this law due to varying molecular interactions. For example, in an acetone/chloroform solution, the individual vapor pressures of the components are lower than expected, resulting in a total vapor pressure below that predicted by Raoult's law, causing a negative deviation.On the other hand, in an ethanol/water...
02:24Ideal Solutions
According to Raoult’s law, the partial vapor pressure of a solvent in a solution is equal or identical to the vapor pressure of the pure solvent multiplied by its mole fraction in the solution. However, Raoult's Law is only valid for ideal solutions. For a solution to be ideal, the solvent-solute interaction must be just as strong as a solvent-solvent or solute-solute interaction. This suggests that both the solute and the solvent would use the same amount of energy to escape to the vapor phase...
01:26The Van der Waals Equation
The ideal gas law is based on two simplifying assumptions: first, that there are no intermolecular attractions between gas molecules, and second, that the volume occupied by the molecules themselves is negligible compared with the volume of the container. However, these assumptions don't hold up under all conditions - specifically, at high pressures and low temperatures, as gas tends to deviate from ideal gas behavior.The van der Waals equation is an enhanced version of the ideal gas law,...
01:59Solution Equilibrium and Saturation
Imagine adding a small amount of sugar to a glass of water, stirring until all the sugar has dissolved, and then adding a bit more. You can repeat this process until the sugar concentration of the solution reaches its natural limit, a limit determined primarily by the relative strengths of the solute-solute, solute-solvent, and solvent-solvent attractive forces. You can be certain that you have reached this limit because, no matter how long you stir the solution, undissolved sugar remains. The...
01:20Chemical Equilibria: Redefining Equilibrium Constant
The effect of an inert salt on the solubility of a sparingly soluble salt is known as the salt effect. The degree of the salt effect varies with the ionic strength of the solution, which in turn depends on the activity of the species in the solution. The activity is expressed as the product of concentration and the activity coefficient of the species.
To calculate the equilibrium constants of solutions of moderately high ionic strength, one must account for the salt effect. This redefined...
To calculate the equilibrium constants of solutions of moderately high ionic strength, one must account for the salt effect. This redefined...
01:29The Colloidal State
The formation of a colloidal system is exemplified by an aqueous solution containing Cl− ions is introduced to another containing Ag+ ions, resulting in the precipitation of solid AgCl as extremely tiny crystals. Instead of settling out as a filterable precipitate, these crystals remain suspended in the liquid, showcasing a colloidal system.A colloidal system involves colloidal particles within the approximate range of 1 to 1000 nm in at least one dimension, dispersed in a medium called the...