title: Mucoadhesive liposomes as ocular delivery system: physical, microbiological, and in vivo assessment.
abstract: BACKGROUND
  Mucoadhesive drug delivery is a promising strategy to overcome ocular biopharmaceutical constraints.
  
  
  OBJECTIVE
  Ciprofloxacin HCl-loaded reverse phase evaporation liposomes were coated with different concentrations and molecular weights of mucoadhesive biocompatible chitosan polymer to form chitosomes. This colloidal mucoadhesive system was evaluated in vitro and in vivo with respect to deliver the antibiotic to ocular surface.
  
  
  CONCLUSIONS
  The results obtained pointed out that liposome coating process resulted in entrapment efficiency reduction and higher chitosan concentration, and molecular weight showed a more pronounced effect. No morphological differences between coated and uncoated liposomes were observed. Diffusion was the drug release mechanism from chitosomes. Concerning rheological behavior, pseudoplastic flow was characteristic to the prepared chitosomal dispersions. In addition, chitosan coating improved the ocular permeation of ciprofloxacin HCl. Microbiologically; this formulated system enhanced antimicrobial activity of ciprofloxacin HCl against both Gram-positive and Gram-negative bacteria. Moreover, this mucoadhesive system was able to inhibit the growth of Pseudomonas aeruginosa in rabbits' eyes for 24 hours when compared to the marketed preparation. In vivo bacterial conjunctivitis model elucidated that symptoms were controlled by the prolonged release formulation such as that done by the marketed product.
authors: Industrial Pharmacy Department, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt.
authors: Mohammed M
authors: MM
authors: Mehanna
authors: Hoda A
authors: HA
authors: Elmaradny
authors: Magda W
authors: MW
authors: Samaha
mesh_terms: D000268:Adhesiveness; D060433:Administration, Ophthalmic; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000494:pharmacology; D048271:Chitosan / Q000737:chemistry*; D002939:Ciprofloxacin / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000494:pharmacology; D003692:Delayed-Action Preparations; D004058:Diffusion; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems; D005260:Female; D006090:Gram-Negative Bacteria / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects; D008081:Liposomes; D008297:Male; D008826:Microbial Sensitivity Tests; D008970:Molecular Weight; D010539:Permeability; D011552:Pseudomonas Infections / Q000188:drug therapy; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D011817:Rabbits; D012212:Rheology; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D008081:Liposomes; D002939:Ciprofloxacin; D048271:Chitosan