Amide pectin: A carrier material for colon-targeted controlled drug release

ABSTRACT In order to deliver bioactive components to the colon, an oral colon‐targeted bioadhesive microparticle delivery system based on pectin was developed. Unmodified pectin exhibited a poor hydrophobicity and weak tablet‐crushing strength. Pectin was modified by an amide reaction, which results in a dramatic decrease in water solubility and viscosity, as well as favorable controlled release properties. Amide pectin (AP) were characterized by Fourier transform infrared spectroscopy (FTIR), Nuclear magnetic resonance (1H‐NMR), and Differential scanning calorimetry (DSC). Results of FTIR and 1H‐NMR revealed that amide groups were introduced into the pectin molecules; DSC analysis exhibited that the thermal stability of pectin was decreased. An in vitro release assay demonstrated that matrix tablets prepared by AP could deliver bioactive components to the colon when the pectin content and hydrophobicity were properly controlled. The relationship between the structure and in vitro release properties of amide pectin suggests that an optimal tablet structure and composition can be responsible for a suitable BSA release rate. The optimal tablets making conditions were using methylcellulose (MC) as tablet adhesive, amidation reaction time of 60 min, drug loading of 0.008 g and tableting pressure of 8 kg/mm. The results indicated that matrix tablets made by AP exhibited good colon‐targeted drug release. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43697.