Preparation and characterization of free films of high amylose/pectin mixtures cross-linked with sodium trimetaphosphate

Graduate Program in Pharmaceutical Sciences, Faculty of Pharmaceutical Sciences, São Paulo State University-UNESP , Araraquara, SP , Brazil.
Drug Development and Industrial Pharmacy (Impact Factor: 2.1). 01/2012; 38(11):1354-9. DOI: 10.3109/03639045.2011.650863
Source: PubMed


High amylose and pectin were mixed at 1:1 mass ratio and cross-linked with sodium trimetaphosphate (STMP) in alkaline medium. Films were prepared from aqueous dispersions of these cross-linked polymer blend at three different concentrations (3, 4 and 5%), by solvent casting method. Characterization of the films included thickness, surface morphology, water uptake, water vapor permeability (WVP), tensile strength measurements and enzymatic digestion. The cross-linking allowed to obtain films with improved mechanical properties and reduced WVP. The high resistance to enzymatic digestion exhibited by these films represents a promising approach to their application in the development of colon drug delivery systems.

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