Dendrimers as drug carriers: Dynamics of PEGylated and methotrexate-loaded dendrimers in aqueous solution

Sanja Natali, Jovan Mijovic

Research output: Contribution to journalArticle


An investigation of the dynamics of aqueous solutions of PEG, PEGylated dendrimers, methotrexate, and PEGylated and drug (methotrexate)-loaded dendrimers was carried out with broadband dielectric relaxation spectroscopy (DRS). Two dielectric dispersions were observed in all systems, and the explanation of their molecular origin was offered. The lower frequency process, characterized by an activation energy of 52.2 kJ/mol, was attributed to motions in ice. The higher frequency process is of the Cole Cole type and is assigned to bound water around PEG and methotrexate molecules. The effect of the average number of attached PEG chains and the average number of encapsulated methotrexate molecules was probed. Our results indicate that the dynamics are independent of these numbers but are a strong function of the composition of the complex. Spectral characteristics and temperature dependence of all relaxation processes are described.

Original languageEnglish (US)
Pages (from-to)3011-3017
Number of pages7
Issue number6
StatePublished - May 11 2010


ASJC Scopus subject areas

  • Organic Chemistry
  • Polymers and Plastics
  • Inorganic Chemistry
  • Materials Chemistry

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