Dynamic Light Scattering and X-ray Photoelectron Spectroscopy characterisation of PEGylated polymer nanocarriers: internal structure and surface properties

In this work nanopheres and nanocapsules are precipitated in confined impinging jets mixers through solvent displacement and characterized. Acetone and water are used as solvent and antisolvent together with polymethoxypolyethylene glycol cyanoacrylate-co-hexadecylcyanoacrylate and Miglyol as copolymer and oil, respectively. Characterization is performed with dynamic light scattering, electrophoretic measurements and for the first time with X-ray photo-electron spectroscopy. Results show that the presence of polyethylene glycol chains seems to be more pronounced on the surface of nanospheres than of nanocapsules . The thickness of the copolymer layer in nanocapsules ranges from 1 to 10 nm, depending on the value of the oil to copolymer mass ratio. Fast dilution is confirmed to have a positive effect in suppressing aggregation but can induce further copolymer precipitation.