Pharmaceutical Research

, Volume 18, Issue 3, pp 323–328 | Cite as

Novel Polymeric Micelles Based on the Amphiphilic Diblock Copolymer Poly(N-vinyl-2-pyrrolidone)-block-poly(D,L-lactide)

  • Amina Benahmed
  • Maxime Ranger
  • Jean-Christophe Leroux


Purpose. The purpose of this work was to synthesize a new amphiphilic diblock copolymer of poly(N-vinyl-2-pyrrolidone and poly(D,L-lactide) (PVP-b-PDLLA) capable of self-assembling into polymeric micelles with multiple binding sites and high entrapment efficiency.

Methods. The copolymer was synthesized by ring-opening polymerization of D,L-lactide initiated by potassium PVP hydroxylate. It was characterized by gel permeation chromatography, 1H- and 13C-NMR spectroscopy. The ability of the copolymer to self-assemble was demonstrated by dynamic and static light scattering, spectrofluorimetry and 1H-NMR. The hydrophobic model drug indomethacin was incorporated into the polymeric micelles by a dialysis procedure.

Results. A series of amphiphilic diblock copolymers based on PVP-b-PDLLA were successfully synthesized. The critical association concentrations in water were low, always below 15 mg/L. Micellar size was generally bimodal with a predominant population between 40 and 100 nm. PVP-b-PDLLA micelles were successfully loaded with the poorly water-soluble drug indomethacin and demonstrated an entrapment efficiency higher than that observed with control poly(ethylene glycol)-b-PDLLA micelles. It was hypothesized that specific interactions with the hydrophilic outer shell could contribute to the increase in drug loading.

Conclusion. PVP-b-PDLLA micelles appear to exhibit multiple binding sites and thus represent a promising strategy for the delivery of a variety of drugs.

poly(N-vinyl-2-pyrrolidone) (PVP) poly(D,L-lactide) (PDLLA) colloids diblock copolymer polymeric micelles drug carrier, indomethacin 


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Copyright information

© Plenum Publishing Corporation 2001

Authors and Affiliations

  • Amina Benahmed
    • 1
  • Maxime Ranger
    • 1
  • Jean-Christophe Leroux
    • 1
  1. 1.Faculty of PharmacyUniversity of MontrealSucc. Centre-ville, Montréal (Canada

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