Related Experiment Video
Updated: Jul 30, 2026
11:11
Determination of Plasma Membrane Partitioning for Peripherally-associated Proteins
Published on: June 15, 2018
The purification of membranes by affinity partitioning
Summary
Biospecific affinity partitioning is a novel method for isolating membranes, organelles, cells, and viruses. This technique utilizes specific ligands to selectively separate target structures in aqueous two-phase systems, enabling efficient purification.
Area of Science:
- Biochemistry
- Cell Biology
- Biotechnology
Background:
- Membrane structures like organelles, cells, and viruses require effective isolation techniques for research.
- Current methods may lack specificity or efficiency in separating complex biological structures.
- Affinity partitioning offers a biospecific approach to target these delicate structures.
Purpose of the Study:
- To introduce and detail affinity partitioning as a preparative method for isolating membranes and membraneous structures.
- To discuss the principles and considerations for developing new affinity partitioning systems.
- To highlight the potential of biospecific affinity partitioning in biological research.
Main Methods:
- Utilizing aqueous polymer two-phase systems, typically polyethylene glycol and dextran.
- Employing biospecific affinity ligands (e.g., lectins, antibodies) conjugated to a phase polymer.
- Optimizing two-phase conditions to facilitate selective partitioning of target membranes.
Main Results:
- Demonstrated the principle of affinity partitioning for separating membraneous structures.
- Identified key factors for successful development of new affinity partitioning protocols.
- Highlighted the need for high ligand receptor densities in target membranes for current applications.
Conclusions:
- Affinity partitioning is a viable preparative method for isolating various biological structures.
- Further development is needed to broaden the application of affinity partitioning with new ligands.
- The method holds promise for advancing purification strategies in cell biology and virology.
Related Concept Videos
01:18Detergent Purification of Membrane Proteins
Detergents are used to purify the integral proteins of the membrane. The hydrophobic portion of the detergent can replace membrane phospholipids while solubilizing the membrane proteins. When detergent monomers reach a specific concentration in a solution called critical micelle concentration (CMC), they form micelles. Above CMC, the concentration of the detergent monomers remains in equilibrium with the micelle. The number of detergent monomers present in the CMC varies for each detergent, and...
01:32Subcellular Fractionation
The homogenate obtained after cell lysis contains various membrane-bound organelles that can be further separated into pure fractions by subcellular fractionation. These isolates are used to study specific cellular components, analyze localized protein activity, and are even employed in diagnostics. Fractionation is typically achieved using centrifugation methods, the most common being density-gradient and differential centrifugation.
Differential Centrifugation
Differential centrifugation is...
Differential Centrifugation
Differential centrifugation is...
01:15Dialysis
Dialysis is a diffusion-based purification process that separates analyte molecules from a complex matrix. This is accomplished by allowing molecules in the solution to pass through a semipermeable membrane into a liquid on the other side. The membrane is usually made of cellulose acetate or cellulose nitrate, and the second liquid must be miscible with the solution. Ions (e.g., chloride or sodium) or organic molecules (e.g., glucose) can pass through the membrane pores, which generally have...
01:03Affinity Chromatography
Affinity chromatography is a powerful technique extensively utilized for separating and purifying specific biomolecules from complex mixtures. It capitalizes on the highly selective binding between an analyte and its counterpart, such as antibody-antigen interactions. The counterpart is immobilized on the stationary phase, forming an affinity column. The stationary phase typically consists of solid support, such as agarose or porous glass beads, immobilizing the affinity ligand. The mobile...