These synthetic molecules consist of two covalently linked homopolymer chains. The
homopolymer chains are designed such that one of them carries hydrophobic functionality the
other one consists of hydrophilic repeating units, i.e. these are macroamphiphiles.
Amphiphilic block copolymers
can self- assemble in the presence of a selective solvent for one
of the blocks to form
various aggregates. The morphology of the structures depends on the
chain size and chemistry
and also on the physical variables such as temperature, etc.
Diblock copolymer vesicles can be formed by various methods including :
a) rehydration in the presence of plasticizer
b) thin film rehydration
We have
also investigated novel ways to engineer the formation of structures
from
amphiphilic
block copolymers. For example, vesicles were prepared from a diblock which
composition
favors micelle formation in water by manipulating the hydrophobic portion
of the
diblock.
An image of a vesicle formed in this way is shown below:
Fluorescence image of a vesicle swollen in the presence of
Texas-Red in the water . The fluorescence from the sample exterior
was quenched by addition of anti-dye.