Fig. 3
From: Nanosensors based on polymer vesicles and planar membranes: a short review
Illustration shows the main concept of SO2-sensing and self-assembly of the vesicles with functionalized surface. The hydrophobic HBPO core of the sensor is blue, the hydrophilic PEO arms are red. The TAA groups (green) undergo proton exchange with cresol red and cresol red-immobilized vesicles (purple) are formed. In the presence of SO2, the protonated yellow cresol red is released [20]