Related Experiment Video
Updated: May 28, 2026
10:08
Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
Structural transition in micelles: novel insight into microenvironmental changes in polarity and dynamics
Arunima Chaudhuri1, Sourav Haldar, Amitabha Chattopadhyay
1Centre for Cellular and Molecular Biology, Council of Scientific and Industrial Research, Uppal Road, Hyderabad 500 007, India.
Chemistry and Physics of Lipids
|October 4, 2011
Summary
Structural transitions in charged micelles alter polarity and packing, affecting molecule ionization. Red edge excitation shift (REES) effectively monitors these micellar organization changes, crucial for drug delivery applications.
Area of Science:
- Physical Chemistry
- Biophysics
- Materials Science
Background:
- Structural transitions in charged micelles are vital for cellular physiology.
- These transitions, induced by ionic strength, alter micellar packing and polarity.
- Micellar polarity influences the ionization states of bound molecules.
Purpose of the Study:
- To investigate how structural transitions in charged micelles affect micellar organization and dynamics.
- To explore the utility of Red Edge Excitation Shift (REES) in monitoring these changes.
- To understand the implications of altered micellar properties for drug incorporation.
Main Methods:
- Inducing structural transitions in charged micelles by altering ionic strength.
- Utilizing Red Edge Excitation Shift (REES) spectroscopy to monitor micellar changes.
- Analyzing probe and peptide behavior within micelles of varying shapes and polarities.
Main Results:
- Shape changes in micelles lead to altered packing and reduced micellar polarity.
- Reduced polarity affects the ionization states of micelle-bound molecules.
- REES effectively monitors changes in micellar organization and dynamics, influenced by probe location.
Conclusions:
- Micellar structural transitions significantly impact micellar organization, dynamics, and polarity.
- REES is a valuable tool for studying these transitions.
- Reduced micellar polarity and tighter packing are key factors in drug incorporation into micellar nanocarriers.
Related Concept Videos
01:30Micelles
Micelle formation is an intricate process that hinges on the properties of amphiphilic or amphipathic molecules and the conditions of the system in which they are found. Amphiphilic molecules, which have both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts, play a critical role in this process.In aqueous environments, these molecules arrange themselves such that their hydrophilic heads are turned towards the water phase, while their hydrophobic tails are oriented away...
01:23Membrane Fluidity
Cell membranes are composed of phospholipids, proteins, and carbohydrates loosely attached to one another through chemical interactions. Molecules are generally able to move about in the plane of the membrane, giving the membrane its flexible nature called fluidity. Two other features of the membrane contribute to membrane fluidity: the chemical structure of the phospholipids and the presence of cholesterol in the membrane.
01:26Membrane Fluidity
Membrane fluidity is explained by the fluid mosaic model of the cell membrane, which describes the plasma membrane structure as a mosaic of components—including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character.
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is a relatively...
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is a relatively...
01:28Induced Electric Dipoles
A permanent electric dipole orients itself along an external electric field. This rotation can be quantified by defining the potential energy because the external torque does work in rotating it. Then, the potential energy is minimum at the parallel configuration and maximum at the antiparallel configuration. While the former is a stable equilibrium, the latter is an unstable equilibrium.
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
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...
01:35Asymmetric Lipid Bilayer
Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...