Polymersomes, Filomicelles, and 'marker of Self' Approaches to Evade Clearance and Maximize Delivery

Polymersomes and Filomicelles are self-assembled polymer shells and cylinders composed of block copolymer amphiphiles. The PEG-based amphiphiles possess an amphiphilicity similar to lipids, but they have much larger molecular weights, and so for this reason comparisons with viral capsids and filaments composed of large polypeptide chains seem highly appropriate. They might also lend some insight into the 'Morphology of Virology'. We will summarize the phase diagrams of both established and novel polymers used to make polymersomes and filomicelles along with descriptions of physicochemical properties such as stability and programmed degradability for controlled release of drugs and RNAi. We will also elaborate ongoing studies of in vivo stealthiness, tumor-shrinkage, and additional efforts that aim to transcend the passive compatability of polymers and exploit 'Marker of Self' molecule(s) used by the body's own cells to evade clearance. The more persistent the carrier in the circulation, the more efficacious the delivery.

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