Pharmaceutical Research

, Volume 12, Issue 5, pp 663–668 | Cite as

Prolonged Blood Circulation in Rats of Nanospheres Surface-Modified with Semitelechelic Poly[N-(2-Hydroxypropyl)methacrylamide]

  • Shigeru Kamei
  • Jindřich Kopeček


Semitelechelic poly[N-(2-hydroxypropyl)methacrylamide]s (ST-PHPMA) containing one amino end-group and differing in molecular weight were synthesized by radical polymerization in the presence of 2-aminoethanethiol (AET) as chain transfer agent. These polymers were covalently attached via amide bonds to the surface of nanospheres based on a copolymer of methyl methacrylate, maleic anhydride, and methacrylic acid. When compared to unmodified nanospheres, those with the surface modified with ST-PHPMA possessed a decreased protein (albumin, IgG, fibrinogen) adsorption in vitro, an increased intravascular half-life as well as a decreased accumulation in the liver after intravenous administration into rats. The higher the molecular weight of the ST-PHPMA, the more pronounced the changes in these properties. The results obtained have clearly demonstrated that covalently attached ST-PHPMA chains are efficient in decreasing the biorecognition of negatively charged (hydrophilic) polymer surfaces.

semitelechelic poly[N-(2-hydroxypropyl)methacrylamide] nanospheres surface modification prolonged blood circulation avoidance of RES 


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Copyright information

© Plenum Publishing Corporation 1995

Authors and Affiliations

  • Shigeru Kamei
    • 1
  • Jindřich Kopeček
    • 1
  1. 1.Department of Pharmaceutics and Pharmaceutical Chemistry/CCCDUniversity of UtahSalt Lake City

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