Optically Triggered Dissociation of Kinetically Stabilized Block Copolymer Vesicles in Aqueous Solution

✍ Scribed by Bin Yan; Jie He; Patrick Ayotte; Yue Zhao

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 415 KB
• Volume: 32
• Category: Article
• ISSN: 1022-1336
• DOI: 10.1002/marc.201100118

✦ Synopsis

Abstract

We demonstrate a strategy for using an optical stimulus to trigger the dissociation of block copolymer (BCP) vesicles in aqueous solution. The BCP, comprising hydrophilic poly(ethylene oxide) (PEO) and a block of poly(methacrylic acid) bearing a number of spiropyran methacrylate comonomer units (P(MAA‐co‐SPMA)), was allowed to firstly self‐assemble into large vesicles in aqueous solution at pH = 3 with protonated carboxylic acid groups, and then become kinetically stable at pH = 8 due to the glassy vesicle membrane of P(MAA‐co‐SPMA). Fast dissociation of the vesicles was achieved through a cascade of events triggered by UV‐induced isomerization from neutral spiropyran to charged merocyanine in the membrane.

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