title: Colon-specific delivery of 5-aminosalicylic acid from chitosan-Ca-alginate microparticles.
abstract: Chitosan-Ca-alginate microparticles for colon-specific delivery and controlled release of 5-aminosalicylic acid after peroral administration were prepared using spray drying method followed by ionotropic gelation/polyelectrolyte complexation. Physicochemical characterization pointed to the negatively charged particles with spherical morphology having a mean diameter less than 9 microm. Chitosan was localized dominantly in the particle wall, while for alginate, a homogeneous distribution throughout the particles was observed. (1)H NMR, FTIR, X-ray and DSC studies indicated molecularly dispersed drug within the particles with preserved stability during microencapsulation and in simulated in vivo drug release conditions. In vitro drug release studies carried out in simulated in vivo conditions in respect to pH, enzymatic and salt content confirmed the potential of the particles to release the drug in a controlled manner. The diffusional exponents according to the general exponential release equation indicated anomalous (non-Fickian) transport in 5-ASA release controlled by a polymer relaxation, erosion and degradation. Biodistribution studies of [(131)I]-5-ASA loaded chitosan-Ca-alginate microparticles, carried out within 2 days after peroral administration to Wistar male rats in which TNBS colitis was induced, confirmed the dominant localization of 5-ASA in the colon with low systemic bioavailability.
authors.affiliation: Ss. Cyril and Methodious University, Faculty of Pharmacy, Vodnjanska 17, 1000 Skopje, Macedonia. krml@ff.ukim.edu.mk
authors.forename: K
authors.initials: K
authors.lastname: Mladenovska
authors.forename: R S
authors.initials: RS
authors.lastname: Raicki
authors.forename: E I
authors.initials: EI
authors.lastname: Janevik
authors.forename: T
authors.initials: T
authors.lastname: Ristoski
authors.forename: M J
authors.initials: MJ
authors.lastname: Pavlova
authors.forename: Z
authors.initials: Z
authors.lastname: Kavrakovski
authors.forename: M G
authors.initials: MG
authors.lastname: Dodov
authors.forename: K
authors.initials: K
authors.lastname: Goracinova
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D001402:B-Lymphocytes / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002118:Calcium / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D048271:Chitosan / Q000737:chemistry*; D003092:Colitis / Q000188:drug therapy / Q000378:metabolism; D003106:Colon / Q000187:drug effects*; D018360:Crystallography, X-Ray; D003692:Delayed-Action Preparations; D004339:Drug Compounding; D016503:Drug Delivery Systems; D004563:Electrochemistry; D005079:Excipients; D005782:Gels; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D019804:Mesalamine / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D008863:Microspheres; D009929:Organ Size / Q000187:drug effects; D010316:Particle Size; D009195:Peroxidase / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D014018:Tissue Distribution
chemical_list: D000464:Alginates; D000894:Anti-Inflammatory Agents, Non-Steroidal; D003692:Delayed-Action Preparations; D005079:Excipients; D005782:Gels; D019804:Mesalamine; D048271:Chitosan; D009195:Peroxidase; D002118:Calcium