Journal of Nanoparticle Research

, Volume 12, Issue 7, pp 2629–2644 | Cite as

Nanoparticles based on novel amphiphilic polyaspartamide copolymers

  • Emanuela Fabiola Craparo
  • Girolamo Teresi
  • Maria Chiara Ognibene
  • Maria Pia Casaletto
  • Maria Luisa Bondì
  • Gennara Cavallaro
Research Paper


In this article, the synthesis of two amphiphilic polyaspartamide copolymers, useful to obtain polymeric nanoparticles without using surfactants or stabilizing agents, is described. These copolymers were obtained starting from α,β-poly-(N-2-hydroxyethyl)-dl-aspartamide (PHEA) by following a novel synthetic strategy. In particular, PHEA and its pegylated derivative (PHEA-PEG2000) were functionalized with poly(lactic acid) (PLA) through 1,1′-carbonyldiimidazole (CDI) activation to obtain PHEA–PLA and PHEA-PEG2000–PLA graft copolymers, respectively. These copolymers were properly purified and characterized by 1H-NMR, FT-IR, and Size Exclusion Chromatography (SEC) analyses, which confirmed that derivatization reactions occurred. Nanoparticles were obtained from PHEA–PLA and PHEA-PEG2000–PLA graft copolymers by using the high pressure homogenization-solvent evaporation method, avoiding the use of surfactants or stabilizing agents. Polymeric nanoparticles were characterized by dimensional analysis, before and after freeze-drying process, and Scanning Electron Microscopy (SEM). Zeta potential measurements and X-ray Photoelectron Spectroscopy (XPS) analysis demonstrated the presence of PEG and/or PHEA onto the PHEA-PEG2000–PLA and PHEA–PLA nanoparticle surface, respectively.


α,β-poly-(N-2-hydroxyethyl)-dl-aspartamide (PHEA) Poly(lactic acid) (PLA) Poly(ethylene glycol) (PEG) Graft copolymers Nanoparticles Drug delivery 



The authors thank MIUR (Ministero dell’Istruzione, dell’Università e della Ricerca) for funding. The authors also thank Dr. Paolo Guerra (Dipartimento di Ingegneria Chimica dei Processi e dei Materiali, Università of Palermo), for ESEM technical support.


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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Emanuela Fabiola Craparo
    • 1
  • Girolamo Teresi
    • 1
  • Maria Chiara Ognibene
    • 1
  • Maria Pia Casaletto
    • 2
  • Maria Luisa Bondì
    • 2
  • Gennara Cavallaro
    • 1
  1. 1.Dipartimento di Chimica e Tecnologie FarmaceuticheUniversità di PalermoPalermoItaly
  2. 2.Istituto per lo Studio dei Materiali NanostrutturatiConsiglio Nazionale delle RicerchePalermoItaly

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