Charged polypeptide vesicles with controllable diameter.

Eric P Holowka; Darrin J Pochan; Timothy J Deming

doi:10.1021/ja053557t

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Charged polypeptide vesicles with controllable diameter.

Eric P Holowka·Darrin J Pochan·Timothy J Deming

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Abstract

We report the preparation and characterization of charged, amphiphilic block copolypeptides that form stable vesicles and micelles in aqueous solution. Specifically, we prepared and studied the aqueous self-assembly of a series of poly(L-lysine)-b-poly(L-leucine) block copolypeptides, KxLy, where x ranged from 20 to 80 and y ranged from 10 to 30 residues, as well as the poly(L-glutamatic acid)-b-poly(L-leucine) block copolypeptide, E60L20. Furthermore, the vesicular assemblies show dynamic properties, indicating a high degree of membrane fluidity. This characteristic provides stimuli-responsive properties to the vesicles and allows fine adjustment of vesicle size using liposome-based extrusion techniques. Vesicle extrusion also provides a straightforward means to trap solutes, making the vesicles promising biomimetic encapsulants.

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Biocompatible Materials Hydrophobic and Hydrophilic Interactions Membrane Fluidity Micelles Microscopy, Electron, Scanning Microscopy, Phase-Contrast Nanotechnology Nanotubes Oligopeptides Peptides Polyglutamic Acid Polylysine Journal Article Research Support, Non-U.S. Gov't

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Eric P Holowka, Darrin J Pochan, Timothy J Deming. 2005-09-07. Charged polypeptide vesicles with controllable diameter.. https://doi.org/10.1021/ja053557t

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