title: Evaluation of potential of Zn-pectinate gel (ZPG) microparticles containing mesalazine for colonic drug delivery.
abstract: OBJECTIVE
  Pectin derivatives have been utilized for colonic drug delivery (CDD). In this study the effects of different formulation variables upon the characteristics of pectinate microparticles (MPs) prepared by ionotropic gelation technique for colonic delivery of mesalazine was investigated.
  
  
  METHODS
  In-vitro drug release of MPs was studied using USP XXIV dissolution apparatus type I, in different fluids e.g. simulated gastric fluid (SGF: pH 1.2), simulated intestinal fluid (SIF: pH 7.4), and simulated colonic fluid (SCF: pH 6.8) of volume 900 ml, at 100 rpm maintained at 37±0.2°C. This study was also performed in the presence of 4% w/v rat caecal content (RCC) using phosphate buffer saline (pH 6.8) as SCF. Gamma scintigraphy study was performed on New Zealand rabbit animal model using (99m) Tc.
  
  
  RESULTS
  The results showed that maximum entrapment of mesalazine (86.1±1.7%) and strength of gel network zinc pectinate gel microparticles (ZPGD2) was achieved in cross-linking solution of pH 1.6. Batch of ZPGD2 showed least swelling ratio and drug release. In RCC medium the t(50%) value of CPG-MPs was 3-4 folds greater than ZPG-MPs. Scintigram showed the residence of ZPG-MPs (filled in enteric coated capsule) in colon more than 9 hrs and delivery of almost all the drug loading dose in colon.
  
  
  CONCLUSIONS
  The results of this study suggest the designed formulation of ZPG-MPs has the potential to serve as a colonic drug delivery system.
authors.affiliation: Delhi Institute of Pharmaceutical Sciences and Research (DIPSAR), University of Delhi, New Delhi.
authors.forename: J
authors.initials: J
authors.lastname: Kawadkar
authors.forename: K
authors.initials: K
authors.lastname: Chauhan Meenakshi
authors.forename: A
authors.initials: A
authors.lastname: Ram