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.

Inulin-based polymer coated SPIONs as potential drug delivery systems for targeted cancer therapy

“…It is water soluble and exhibits high hydroxyl functional groups available for common coupling reactions [24]. Various studies have dealt with its chemical modification in order to obtain biocompatible drug delivery systems (DDS), including hydrogels [25], nanoparticles [26], micelles [6] and [27], and macromolecular bioconjugates [28]. Being inulin versatile and highly functionalizable [29] and [30], here we focused our attention on the synthesis of an amphiphilic inulin derivative capable of coating SPIONs once placed in aqueous media.…”

Realization of polyaspartamide-based nanoparticles and in vivo lung biodistribution evaluation of a loaded glucocorticoid after aerosolization in mice

“…Derivatization of PHEA with PEG2000 to obtain PHEA-PEG2000 graft copolymer and its characterization was carried out according to a procedure described elsewhere (Craparo et al, 2006). The DD in PEG (DDPEG) of PHEA-PEG2000 graft copolymer used in this study, determined by 1 H-NMR in DMSO-d6, was 4.0  0.5 mol%; w M of PHEA-PEG2000 used in this study resulted to be 38.7 kDa (Mw/Mn = 1.8).…”

Fluorinated derivatives of a polyaspartamide bearing polyethylene glycol chains as oxygen carriers

“…PHEA-PEG derivative was prepared and purified according to a previously reported procedure [20]. In particular, to a PHEA solution (40 mg/ml) in anhydrous DMF a proper amount of bis(4-nitrophenyl) carbonate (PNPC) was added in a such way to have X = moles of PNPC/moles of PHEA repeating units equal to 0.1.…”