Polymeric micelles: polyethylene glycol-phosphatidylethanolamine (PEG-PE)-based micelles as an example.

One of the renowned nanosized pharmaceutical carriers for delivery of poorly soluble drugs, especially, in cancer, is micelles, which are self-assembled colloidal particles with a hydrophobic core and hydrophilic shell. Among the micelle-forming compounds, micelles made of polyethylene glycol-phosphatidylethanolamine (PEG-PE) have gained more attention due to some attractive properties such as good stability, longevity, and ability to accumulate in the areas with an abnormal vasculature via the enhanced permeability and retention effect (into the areas with leaky vasculature, such as tumors). Additionally these micelles can be made "targeted" by attaching specific targeting ligand molecules to the micelle surface or can be comprised of stimuli-responsive amphiphilic block copolymers. Addition of second component such as surfactant or another hydrophobic material to the main micelle forming material further improves the solubilizing capacity of micelles without compromising their stability. Micelles carrying various contrast agents may become the imaging agents of choice in different imaging modalities. Here, we have discussed various protocols for preparation and evaluation of PEG-PE-based micelles.