Preparation and characterization of in-situ ionic cross-linked pectin films: II. Biodegradation and drug diffusion

In the present study the enzymatic biodegradation of a series of calcium pectinate (CaP) films, produced by in-situ crosslinking of pre-formed low methoxy pectin films in a calcium chloride (CaCl2) solution, has been assessed. The degradation level was determined by measuring the concentration of short chain fatty acid salts (SCFA), which are the natural metabolites of pectin. To this end an ex-vivo model, mimicking the colon's environment, was utilized. The results showed that a fully calcified film from a high concentration of CaCl2 solution did not exhibit any tendency to biodegradability throughout the test time. Contrastively, a low concentration of the crosslinking solution resulted in fully calcified films which could clearly present considerably higher biodegradability. SEM analysis was used to characterize the surface of CaP films after an exposure to human feces. The permeability of CaP films to different model drugs was also tested.