title: Preparation of biocompatible carboxymethyl chitosan nanoparticles for delivery of antibiotic drug.
abstract: OBJECTIVE
  To prepare biocompatible ciprofloxacin-loaded carboxymethyl chitosan nanoparticles (CCC NPs) and evaluate their cell specificity as well as antibacterial activity against Escherichia coli in vitro.
  
  
  METHODS
  CCC NPs were prepared by ionic cross-linking method and optimized by using Box-Behnken response surface method (BBRSM). Zeta potential, drug encapsulation, and release of the obtained nanoparticles in vitro were thoroughly investigated. Minimum inhibitory concentration (MIC) and killing profiles of free or ciprofloxacin-loaded nanoparticles against Escherichia coli were documented. The cytotocity of blank nanoparticles and cellular uptake of CCC NPs were also investigated.
  
  
  RESULTS
  The obtained particles were monodisperse nanospheres with an average hydrated diameter of 151 ± 5.67 nm and surface of charge -22.9 ± 2.21 mV. The MICs of free ciprofloxacin and CCC NPs were 0.16 and 0.08 μg/mL, respectively. Blank nanoparticles showed no obvious cell inhibition within 24 h, and noticeable phagocytosis effect was observed in the presence of CCC NPs.
  
  
  CONCLUSIONS
  This study shows that CCC NPs have stronger antibacterial activity against Escherichia coli than the free ciprofloxacin because they can easily be uptaken by cells. The obtained CCC NPs have promising prospect in drug delivery field.
authors.affiliation: College of Pharmacy, Liaoning Medical University, Jinzhou 121000, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhao
authors.forename: Bingya
authors.initials: B
authors.lastname: Zhu
authors.forename: Yunhong
authors.initials: Y
authors.lastname: Jia
authors.forename: Wenjiu
authors.initials: W
authors.lastname: Hou
authors.forename: Chang
authors.initials: C
authors.lastname: Su
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D001672:Biocompatible Materials / Q000008:administration & dosage / Q000737:chemistry; D002470:Cell Survival / Q000187:drug effects; D048271:Chitosan / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D002939:Ciprofloxacin / Q000494:pharmacology; D016503:Drug Delivery Systems; D004926:Escherichia coli / Q000187:drug effects; D006801:Humans; D053758:Nanoparticles / Q000008:administration & dosage / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; C514968:carboxymethyl-chitosan; D002939:Ciprofloxacin; D048271:Chitosan