Sustained-release of oxytetracycline from chitosan microspheres prepared by interfacial acylation and spray hardening methods

Mi Fwu-Long, Tsung Bi Wong, Shin Shing Shyu

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28 Citations (Scopus)


Chitosan microspheres containing oxytetracycline (OTC), an antibiotic agent, were prepared by spray hardening and interfacial acylation methods. The object of this study was to prepare oxytetracycline-containing microspheres for oral administration and injection using different molecular weight (Mw 70,000 ~ 2,000,000) of chitosan. By the spray hardening method, microspheres with particle sizes between 5 and 30 μm could be obtained and might be suitable for intramuscular injection. On the other hand, chitosan microspheres with the ability to extend the dissolution period of oxytetracycline in low pH medium were also prepared by the interfacial acylation method. The result indicated that the releasing of oxytetracycline from various acylated chitosan microspheres was decreased with increasing the molecular weight of chitosan and would show well sustained-release property. Besides, the morphology of various microspheres and crystalline form transition of oxytetracycline were also studied using electron scanning microscope and X-ray analysis.

Original languageEnglish
Pages (from-to)577-591
Number of pages15
JournalJournal of Microencapsulation
Issue number5
Publication statusPublished - Sep 1997
Externally publishedYes



  • Antibiotic agent
  • Chitosan
  • Interfacial acylation
  • Microspheres
  • Oxytetracycline
  • Spray hardening

ASJC Scopus subject areas

  • Chemistry (miscellaneous)
  • Pharmaceutical Science
  • Chemical Engineering(all)
  • Pharmacology

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