Chitosan–Chondroitin Sulfate Based Matrix Tablets for Colon Specific Delivery of Indomethacin

Abstract

Abstract. The different approaches for targeting orally administered drugs to the colon include coating with pH-dependent polymers, design of time-release dosage forms, and the utilization of carriers that are degraded exclusively by colonic bacteria. The aim of the present study was to develop a single unit, sitespecific drug formulation allowing targeted drug release in the colon. Matrix tablets were prepared by wet granulation using cross-linked chitosan (ChI) and chondroitin sulfate (ChS) polysaccharides as binder and carrier. ChS was used to form polyelectrolyte complexes (PEC) with ChI, and its potential as a colon-targeted drug carrier was investigated. Indomethacin was used as a model drug. The ChI and ChS PEC was characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and powder X-ray diffraction studies (XRD). The matrix tablets were tested in vitro for their suitability as colon-specific drug delivery systems. FTIR demonstrated that the PEC forms through an electrostatic interaction between the protonated amine (NH 3 + ) group of ChI with the free carboxylate (COO − ) group and sulfate (SO 4 2− ) group of ChS. DSC and XRD indicated that the PEC has different thermal characteristics from ChI or ChS. The dissolution data demonstrates that the dissolution rate of the tablet is dependent upon the concentration of polysaccharide used as binder and matrix and time of cross-linking. The study confirmed that selective delivery of indomethacin to the colon can be achieved using cross-linked ChI and ChS polysaccharides.

Eudragit ® FS 30 D polymeric films containing chondroitin sulfate as candidates for use in coating seeking modified delivery of drugs

“…The other combinations containing 5%, 10% and 20% of CS were similar to the control. In the upper spectral region, at 3000 cm -1 , there was a greater intensity of bands proportional to the addition of CS, which may be associated with the OH -group common to both CS and EFS (Evonik, 2015;Amrutkar, Gattani, 2009). When comparing the spectrum of the control film and spectra of films associated with CS, the non-appearance of new bands can be verified, except CS absorption bands.…”

“…In addition to this favorable characteristic, natural polymers are found in abundance, they have low toxicity, low cost and flexibility to chemical modification, making them suitable for use in pharmaceutical coatings (Amrutkar, Gattani, 2009). Chondroitin sulfate is a natural polymer studied as a carrier of drugs in the research and development of new therapeutic systems designed for controlled and site-specific delivery (Bunhak et al, 2015;Amrutkar, Gattani, 2009).…”

Formulation and Evaluation of Isorhamnetin Loaded Poly Lactic-Co-Glycolic Acid Nanoparticles

“…From the FT-IR results, we concluded that -C-N-, -C=C-, N-H, C-N, N-O, O-H, C-Cl, C-Br, and C-H are the functional groups present in IR-PLGA NPs. Previously, FTIR analysis was also performed by other investigators to characterize this type of interactions between drugs and PLGA polymer [35][36][37].…”

Melt-Extruded Eudragit® FS-Based Granules for Colonic Drug Delivery

“…Oral dosage forms delivering drug to colon are highly desirable to treat a variety of bowel diseases such as colon cancer, ulcerative colitis, and local inflammation (1). The target delivery offers the benefit of the direct treatment at the disease sites and fewer systematic side effects.…”