Films from resistant starch-pectin dispersions intended for colonic drug delivery

• Published in: Carbohydrate polymers 2014, Vol.99, p.140-149
• Main Authors: Bagliotti Meneguin, Andréia, Stringhetti Ferreira Cury, Beatriz, Evangelista, Raul Cesar
• Format: Article
• Language: English
• Subjects: Applied sciences; Biological and medical sciences; Biomimetic Materials - chemistry; Birefringence; Colon - metabolism; Crystallization; Dissolution; Drug Carriers - chemistry; Enzymatic digestion; Exact sciences and technology; Free film; General pharmacology; Glycerol - chemistry; Glycols - chemistry; Hardness; Humans; Medical sciences; Natural polymers; Pancreatin - chemistry; Pectin; Pectins - chemistry; Permeability; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Physicochemistry of polymers; Plasticizers - chemistry; Resistant starch; Rheology; Starch - chemistry; Starch and polysaccharides; Steam; X-Ray Diffraction
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2013.07.077

•Starch was retrograded to prepare films by solvent casting method.•Films were evaluated by mechanical, X-ray diffraction and enzymatic digestion analysis.•Films properties were influenced by proportion of polymer and plasticizer presence. Free films were obtained by the solvent casting method from retrograded starch-pectin dispersions at different polymer proportions and concentrations with and without plasticizer. Film forming dispersions were characterized according to their hardness, birefringence and rheological properties. The polymer dispersions showed a predominantly viscous behavior (G″>G′) and the absence of plasticizers lead to building of stronger structures, while the occurrence of Maltese crosses in the retrograded dispersions indicates the occurrence of a crystalline organization. Analyses of the films included mechanical properties, thickness, superficial and cross sectional morphology, water vapor permeability, liquid uptake ability, X-ray diffractometry, in vitro dissolution and enzymatic digestion. The high resistant starch content (65.8–96.8%) assured the resistance of materials against enzymatic digestion by pancreatin. Changes in the X-ray diffraction patterns indicated a more organized and crystalline structure of free films in relation to isolated polymers. Increasing of pectin proportion and pH values favored the dissolution and liquid uptake of films. Films prepared with lower polymer concentration presented better barrier function (WVP and mechanical properties).