Core crosslinkable polymeric micelles from PEG–lipid amphiphiles as drug carriers

Core crosslinkable micelles were prepared based on PEG–lipid amphiphiles. The branched hydrophobic domain was prepared by acylation of 2,2-bis(hydroxymethyl)propionic acid (DMPA) with 10-undecenoyl chloride and pyridine as catalyst. Monohydroxyl poly(ethylene glycol) (m-PEG) was conjugated onto the hydrophobic domain to form the branched polymeric amphiphiles. Following micelle formation of the amphiphiles, the vinylic groups at the peripheral ends of the 10-undecenoyl acid chains were polymerized with AIBN to crosslink the hydrophobic domains in aqueous solution. The solution properties of the crosslinked micelles were evaluated in various solvents and temperatures; relative to the uncrosslinked micelle controls, the core crosslinked micelles demonstrated improved thermodynamic stability in solution to high temperatures and non-selective solvents. Furthermore, the core crosslinked micelles show much higher drug loading capacity (nearly 80 wt%) than the uncrosslinked micelles (ca. 10 wt%).