title: Design and development of gliclazide-loaded chitosan microparticles for oral sustained drug delivery: in-vitro/in-vivo evaluation.
abstract: OBJECTIVE
  The objective of this study was to prepare gliclazide-chitosan microparticles with tripolyphosphate by ionic crosslinking.
  
  
  METHODS
  Chitosan microparticles were produced by emulsification and ionotropic gelation. The effects of process variables including chitosan concentration, pH of tripolyphosphate solution, glutaraldehyde volume and release modifier agent such as pectin added to the tripolyphosphate crosslinking solution were evaluated. The microparticles were examined with scanning electron microscopy, infrared spectroscopy and differential scanning colorimetry. The serum glucose lowering effect of gliclazide microparticles was studied in streptozotocin-diabetic rabbits compared with the effect of pure gliclazide powder and gliclazide commercial tablets.
  
  
  RESULTS
  The particle sizes of tripolyphosphate-chitosan microparticles were over the range 675-887 µm and the loading efficiency of drug was greater than 94.0%. In-vivo testing of the gliclazide-chitosan microparticles in diabetic rabbits demonstrated a significant antidiabetic effect of gliclazide-chitosan microparticles after 8 h that lasted for 18 h compared with gliclazide powder, which produced a maximum hypoglycaemic effect after 4 h.
  
  
  CONCLUSIONS
  The results suggests that gliclazide-chitosan microparticles are a valuable system for the sustained delivery of gliclazide.
authors.affiliation: Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia. nsybarakat@yahoo.com
authors.forename: Nahla S
authors.initials: NS
authors.lastname: Barakat
authors.forename: Alanood S
authors.initials: AS
authors.lastname: Almurshedi
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects; D002152:Calorimetry, Differential Scanning / Q000379:methods; D048271:Chitosan / Q000008:administration & dosage / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry; D003692:Delayed-Action Preparations; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000188:drug therapy; D004337:Drug Carriers / Q000008:administration & dosage / Q000737:chemistry*; D015195:Drug Design; D005907:Gliclazide / Q000008:administration & dosage / Q000737:chemistry*; D005976:Glutaral / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000737:chemistry*; D008297:Male; D008863:Microspheres; D010316:Particle Size; D010368:Pectins / Q000737:chemistry; D011122:Polyphosphates / Q000737:chemistry; D011208:Powders / Q000008:administration & dosage / Q000737:chemistry; D011817:Rabbits; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013607:Tablets / Q000008:administration & dosage / Q000737:chemistry
chemical_list: D001786:Blood Glucose; D003432:Cross-Linking Reagents; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D007004:Hypoglycemic Agents; D011122:Polyphosphates; D011208:Powders; D013607:Tablets; D010368:Pectins; D048271:Chitosan; D005907:Gliclazide; C005692:triphosphoric acid; D005976:Glutaral