What are polymeric micelles?
What are polymeric micelles?
Polymeric micelles are nanoscopic core/shell structures formed by amphiphilic block copolymers. Both the inherent and modifiable properties of polymeric micelles make them particularly well suited for drug delivery purposes. Relevant properties discussed include micellar association, morphology, size and stability.
How do polymeric micelles work?
The functionality of polymeric micelles depends on their core–shell structure, whereby the hydrophobic core carries and protects the drug, while the hydrophilic shell supports and stabilizes the hydrophobic core in the aqueous medium and enhances the water solubility of the polymers; and this also benefits …
Why is a polymer micelle?
Polymeric micelles (PMs) are nanocarriers that are formed by spontaneous arrangement of amphiphilic block copolymers in aqueous solutions. These nanoparticles have a hydrophobic core–hydrophilic shell architecture that facilitates the loading of hydrophobic drugs into the core.
What are advantages of micelles?
Additional advantages of micelles include reduced side effects of the encapsulated drug, easy and reproducible scale-up, the ability to slow down opsonization and the possibility of longer circulation times when hydrophilic moieties such as PEG, that provide an effective steric barrier, are incorporated in the micelles …
What are the types of micelles?
Micelles are usually spherical ranging in size from 2 to 20 nm depending on composition. The most common methods for micelle preparation include oil in water emulsion [98,99], solvent evaporation [100,101], solid dispersion, and dialysis methods [97,102].
Why do micelles form?
Micelles are formed by self-assembly of amphiphilic molecules. The structures contain hydrophilic/polar region (head) and hydrophobic/nonpolar region (tail) . Micelles are formed in aqueous solution whereby the polar region faces the outside surface of the micelle and the nonpolar region forms the core.
How do micelles work?
Micelles act as emulsifiers that allows a compound that is usually insoluble in water to dissolve. Detergents and soap work by inserting the long hydrophobic tails from soap into the insoluble dirt (such as oil) while the hydrophilic head face outside and surround the nonpolar dirt.
What is Alcosol give an example?
(i) Alcosol: A colloidal solution having alcohol as the dispersion medium and a solid substance as the dispersed phase is called an alcosol. For example: colloidal sol of cellulose nitrate in ethyl alcohol is an alcosol. For example: starch sol or gold sol.
What causes micelle?
This phase is caused by the packing behavior of single-tail lipids in a bilayer. The difficulty filling all the volume of the interior of a bilayer, while accommodating the area per head group forced on the molecule by the hydration of the lipid head group, leads to the formation of the micelle.
What is micellization process?
The driving mechanism for micellization is the transfer of hydrocarbon chains from water into the oil-like interior. Compared to the increase of entropy of the surrounding water molecules, this hydrophobic interaction is relatively small. The water molecules are highly ordered around the hydrocarbon chain.
Why are peg-based micelles a novel drug delivery system?
Polymeric micelles (Figure 19.2) serve as a novel drug delivery system due to their target specificity and controlled release of hydrophobic anticancer drugs. PEG-based micelles are biocompatible and biodegradable.
What can be done with a polymeric micelle?
Polymeric micelles are becoming the focus of research and development of neuron-targeted drug delivery. Micelles composed of polymer and lipids as an amphipathic system have a greater advantage in bioimaging and diagnosis as compared to liposome and lipid-based NPs .
How are micelles being used to treat cancer?
The delivery of chemotherapeutic drugs to treat tumors is one of the most advanced areas of research using polymer micelles. Two approaches have been explored to enhance delivery of drug-loaded polymer micelles to the tumor sites: 1) passive targeting and 2) vectorized targeting.
What is the potential of PEG based copolymer micelle?
PEG-based amphiphilic block copolymer micelle carriers possess significant potential for improving drug solubility and stability.