Preparation of injectable auto-forming alginate gel containing simvastatin with amorphous calcium phosphate as a controlled release medium and their therapeutic effect in osteoporosis model rat

  • Tomoko Ito
  • Mami Saito
  • Tomohiro Uchino
  • Mamoru Senna
  • Michele Iafisco
  • Maria Prat
  • Lia Rimondini
  • Makoto Otsuka


Highly soluble amorphous calcium phosphate powder (ACP) was added to the alginate gel as a buffering agent, in an attempt to enable widely controlled release while avoiding an acidification of the gel-environment. Therapeutic effects of the ACP-containing alginate gel which slowly releases a drug, simvastatin, on osteoporosis model rats were examined. A model drug, simvastatin, incorporated in the alginate gel with ACP up to 0.5%, was continuously released for a long time under the acidic condition. The release rate was controlled by the amount of ACP, serving as a buffer to suppress acidity. When the alginate solution intramuscularly injected in the rat, a soft gel was formed in the injected site. Simvastatin released from the gel containing 0.5% of ACP showed high therapeutic effect on osteoporosis rat. Thus, the present injectable long-sustained release system is expected to be a novel drug delivery controlling device.


Alginate Simvastatin Bone Mineral Content Simulated Body Fluid Sodium Alginate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was partly supported by the Japan Society for the Promotion of Science (nos. 21700494).


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Tomoko Ito
    • 1
  • Mami Saito
    • 2
  • Tomohiro Uchino
    • 1
    • 3
  • Mamoru Senna
    • 1
    • 4
  • Michele Iafisco
    • 5
    • 6
  • Maria Prat
    • 5
  • Lia Rimondini
    • 5
  • Makoto Otsuka
    • 1
    • 2
  1. 1.Research Institute of Pharmaceutical Sciences, Musashino UniversityTokyoJapan
  2. 2.Faculty of Pharmaceutical Sciences, Musashino UniversityTokyoJapan
  3. 3.College of Engineering, Nihon UniversityFukushimaJapan
  4. 4.RIKEN Innovation CenterSaitamaJapan
  5. 5.Dipartimento di Scienze Mediche, Università del Piemonte OrientaleNovaraItaly
  6. 6.Dipartimento di Chimica “G. Ciamician”, Alma Mater Studiorum, Università di BolognaBolognaItaly

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