Fluorescent and “breathable” CO2 responsive vesicles inspired from green fluorescent protein

Abstract

The design of green fluorescent protein (GFP) chromophore labeled, CO₂ responsive vesicles that can mimic the breathing of jellyfish is described. The vesicles were obtained via the self-assembly of a di-block copolymer bearing a hydrophilic poly(ethylene glycol) (PEG) segment and a hydrophobic, CO₂ responsive poly((diethylamino)ethyl methacrylate) (PDEAEMA) segment, with a GFP chromophore between the two blocks. Like the breathing of a jellyfish, the vesicles’ size and fluorescence changed significantly upon exposure to CO₂, as confirmed by morphology observation and fluorescence measurements. Further analysis suggested that the “breathing” of the vesicles is reversible under a continuous CO₂/N₂ gas flow. The “breathing” behavior of the fluorescent vesicles was also directly observable under a confocal microscope.