Self‐Assembly of a Hydrophobic Polypeptide Containing a Short Hydrophilic Middle Segment: Vesicles to Large Compound Micelles

Abstract

AbstractThis report describes a facile route to prepare the vesicles and large compound micelles (LCMs) from a series of poly(ε‐benzyloxycarbonyl L‐lysine)‐block‐poly[diethylene glycol bis(3‐amino propyl) ether]‐block‐poly(ε‐benzyloxycarbonyl L‐lysine) (PZLL‐DGBE‐PZLL) in their water solution, depending on molecular weight of the polypeptides. A pyrene probe is used to demonstrate the aggregate formation of PZLL‐DGBE‐PZLL in solution, and also to measure their critical micelle concentration as a function of molecular weight of the polymer. Transmission electron microscopy, atomic force microscopy, dynamic light scattering and confocal laser scanning microscopy are used to observe their aggregate morphologies. Rhodamine B is used as a fluorescent probe to confirm the structure of large compound micelles composed of many reverse micelles with aqueous cores. These polypeptides are prepared by ring‐opening polymerization of α‐amino acid N‐carboxyanhydrides with a small molecule as the initiator. Their structures are confirmed by NMR and SEC‐MALLS. These vesicles and large compound micelles are extremely expected to be used in drug delivery.magnified image