title: In vitro characterisation of chitosan based xerogels for potential buccal delivery of proteins.
abstract: Chitosan and thiolated-chitosan based xerogels have been prepared by lyophilising aqueous gels of the polymers incorporating glycerol, d-mannitol and BSA with an annealing process. Analytical characterisation was by circular dichroism, infrared spectroscopy, X-ray diffraction and scanning electron microscopy. Swelling capacities of 1,110 ± 23.3% and 480 ± 18.2% were obtained for the chitosan and TG-chitosan xerogels respectively. Thiolation caused improved in vitro mucoadhesive properties by demonstrating peak adhesive force of 4.5 ± 0.7 and 5.8 ± 0.2N, and total work of adhesion of 6.5 ± 1.0 and 19 ± 0.8 mJ for chitosan and thiolated-chitosan xerogels respectively. In vitro drug dissolution studies using Bradford's assay showed BSA release of 91.5 ± 3.7% and 94.4 ± 7.3% from the chitosan and thiolated-chitosan xerogels respectively. These results demonstrate the potential of developing lyophilised thiolated-chitosan xerogels with optimised mucoadhesion characteristics for buccal mucosa delivery of protein based drugs.
authors.affiliation: Department of Pharmaceutical, Chemical and Environmental Sciences, School of Science, University of Greenwich at Medway, Chatham Maritime, Kent ME4 4TB, UK.
authors.forename: Isaac
authors.initials: I
authors.lastname: Ayensu
authors.forename: John C
authors.initials: JC
authors.lastname: Mitchell
authors.forename: Joshua S
authors.initials: JS
authors.lastname: Boateng
mesh_terms: D048271:Chitosan / Q000737:chemistry*; D005782:Gels / Q000737:chemistry*; D066298:In Vitro Techniques; D009055:Mouth / Q000737:chemistry*; D011506:Proteins / Q000008:administration & dosage*
chemical_list: D005782:Gels; D011506:Proteins; D048271:Chitosan