An Enteric DualControlled Gastrointestinal Therapeutic System of Salmon CalcitoninI: Preparation, Characterization, and Preclinical Bioavailability in Rats Academic Article uri icon


  • Conventional dosage forms are disadvantageous for peptide drugs having short half-lives because of cyclic under- or overdosing and problems of patient compliance. The matrix or reservoir type of controlled-release dosage forms provide an alternative. However, bioavailability fluctuations due to gastric pH variations continue to be a problem for many drug candidates. Osmotically controlled drug delivery systems provide a means of eliminating the effect of pH on drug release. The objective of this study was to formulate salmon calcitonin (sCT), a hypocalcemic hormone, and turkey ovomucoid (serine protease inhibitor) along with glycyrrhetinic acid (absorption enhancer) as a bilayered, osmotically controlled tablet coated with a semipermeable membrane of cellulose acetate. Coating was achieved using a Strea-1 fluidized bed coater. Orifices were drilled for drug release and enteric coating was applied in order to bypass the duodenum region. Comparative studies for the drug-additive interactions were performed using X-ray diffraction, differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, and gel electrophoresis. Dissolution was carried out in HCl (0.1 N, pH 1.2) for 2 hr followed by phosphate buffer (pH 7.4) for 4 hrs. Results of X-ray diffraction, DSC, FTIR, and gel electrophoresis did not indicate a strong interaction or defragmentation. Dissolution studies confirmed the enteric and dual-controlled release of sCT and ovomucoid.

published proceedings

  • Clinical Research and Regulatory Affairs

author list (cited authors)

  • Shah, R. B., Nutan, M., & Khan, M. A.

citation count

  • 3

complete list of authors

  • Shah, Rakhi B||Nutan, Mohammad||Khan, Mansoor A

publication date

  • January 2004