Direct visualisation of micelles of Pluronic block copolymers in aqueous solution by cryo-TEM

Micelles formed by (ethylene oxide) (propylene oxide) (ethylene oxide) trib lock copolymers (Pluronic F127 and L64) in aqueous solutions have been visu alised by cryogenic transmission electron microscopy (cryo-TEM). The resolu tion achieved allows detailed inspection of the individual micelles, their size, shape, core-shell structure as well as long-range order. The dependen ce of the microstructure on the concentration of the solution as well as on the type (block sizes) of the Pluronic polymer are reported and demonstrat e the sensitivity of the method to these parameters.