title: The use of natural biopolymer of chitosan as biodegradable beads for local antibiotic delivery: release studies.
abstract: BACKGROUND
  Chitosan is a naturally occurring biopolymer which has been widely used in a variety of biomedical applications including local antibiotic delivery due to its excellent mechanical properties, biodegradability and biocompatibility. Beads are spherical, porous carriers which are prepared from various materials including chitosan.
  
  
  OBJECTIVE
  The current study aimed to fabricate a new controlled delivery system for local anti-infective treatment and to study its release behavior.
  
  
  METHODS
  Twenty beads were prepared from 1% or 2% chitosan solutions and immersed in vancomycin (VM) or teicoplanin (TN) solutions. The antibiotic release kinetics was determined by linear regression analysis supposing first order kinetics.
  
  
  RESULTS
  Immersion for 3 h resulted in significant increase in the total TN release that differed from 0.5 h of immersion, except for the 1% beads immersed in VM. Increasing the chitosan concentration significantly increased the total release and antibiotic load of beads. The release of TN was more delayed compared to that of VM, which allowed a gradual release beyond 3 days. The half-life (mean ± SEM) of both types of TN-containing beads was significantly extended for 3 h immersion in comparison to 0.5 h immersion (26.1 ± 5.9 vs 10.9 ± 1.0 and 17.0 ± 2.1 vs 5.1 ± 1.9; P < 0.001). However, neither increasing the chitosan concentration, nor immersion time did result in any significant increase in the release of VM.
  
  
  CONCLUSIONS
  The current study demonstrated an improved control of TN release impregnated in beads. It can be concluded that chitosan beads might be considered as a novel carrier for TN delivery to infected bone for local anti-infective therapy.
authors.affiliation: Targeted Drug Delivery Research Center, Department of Pharmaceutics, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors.forename: Jebraeel
authors.initials: J
authors.lastname: Movaffagh
authors.affiliation: Targeted Drug Delivery Research Center, Department of Pharmaceutics, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Ghodsi
authors.affiliation: Biotechnology Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors.forename: Bibi Sedigheh
authors.initials: BS
authors.lastname: Fazly Bazzaz
authors.affiliation: Targeted Drug Delivery Research Center, Department of Pharmaceutics, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, IR Iran ; Pharmacological Research Center of Medicinal Plants, School of Medicine, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors.forename: Sayyed Abolghassem
authors.initials: SA
authors.lastname: Sajadi Tabassi
authors.affiliation: Department of Basic Sciences, Fcaulty of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, IR Iran.
authors.forename: Hamideh
authors.initials: H
authors.lastname: Ghodrati Azadi
keywords: Chitosan; Cross-Linking Reagents; Delayed-action Preparations; Teicoplanin