title: PEGylated Nanoparticles based on a polyaspartamide. preparation, physico-chemical characterization, and intracellular uptake.
abstract: Nanoparticles with different surface PEGylation degree were prepared by using as starting material alpha,beta-poly(N-2-hydroxyethyl)-d,l-aspartamide (PHEA). PHEA was functionalized with a PEG amino-derivative for obtaining PHEA-PEG(2000) copolymer. Both PHEA and PHEA-PEG(2000) were derivatized with methacrylic anhydride (MA) for obtaining poly(hydroxyethylaspartamide methacrylated) (PHM) and poly(hydroxyethylaspartamide methacrylated)-PEGylated (PHM-PEG(2000)), respectively. Nanoparticles were obtained by UV irradiation of an inverse microemulsion, using as internal phase an aqueous solution of PHM alone or of the PHM/PHM-PEG(2000) mixture at different weight ratio and as external phase a mixture of propylene carbonate and ethyl acetate. Obtained nanoparticles were characterized by FT-IR analysis, dimensional analysis, and TEM micrography. XPS analysis and zeta potential measurements demonstrated the presence of PEG onto the nanoparticle surface. Moreover, the partial degradation of nanoparticles in the presence of esterase as a function of time was demonstrated. Finally, nanoparticles did not possess any cytotoxic activity against K-562 cells and were able to escape from phagocytosis depending on the surface PEGylation degree.
authors.affiliation: Dipartimento di Chimica e Tecnologie Farmaceutiche, Università di Palermo, via Archirafi, 32-90123 Palermo, Italy.
authors.forename: Emanuela F
authors.initials: EF
authors.lastname: Craparo
authors.forename: Gennara
authors.initials: G
authors.lastname: Cavallaro
authors.forename: Maria L
authors.initials: ML
authors.lastname: Bondì
authors.forename: Delia
authors.initials: D
authors.lastname: Mandracchia
authors.forename: Gaetano
authors.initials: G
authors.lastname: Giammona
mesh_terms: D006801:Humans; D020014:K562 Cells; D009682:Magnetic Resonance Spectroscopy; D008689:Methacrylates / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles; D010316:Particle Size; D010455:Peptides / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014466:Ultraviolet Rays
chemical_list: D008689:Methacrylates; D010455:Peptides; C008965:alpha,beta-poly((2-hydroxyethyl)-aspartamide); D011092:Polyethylene Glycols