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Avalia??o da pectina fosfatada aplicada na forma??o de filmes isolados: Material candidato a novos sistemas para libera??o modificada de fármacosDOI: 10.1590/S1516-93322008000200006 Keywords: phosphated pectin, free films, α-gluco-olygosaccharides, eudragit? rs 30 d, drugs [modified release]. Abstract: phosphated pectin (pect-tmft) together with α-gluco-oligossacaride (bioecolians?) were incorporated into aqueous dispersion of polymethacrylate (eudragit? rs 30 d) to obtain free films by the casting process (50oc) in teflon? plate. pect-tmft and bioecolians? were added into dispersions of eudragit ? rs 30 d at different rates: 90:05:05, 80:10:10 and 70:20:10 (4% p/v). triethyl citrate (tec) was used as plasticizer (20% of mass of the polymethacrylate). the proposed dispersions showed film formation ability. the free films were characterized by the determination of water vapour transmission (wvt), by the swelling index (ii%) in fluids of gastric simulation (fgs) and intestinal (fis) and by scanning electron microscopy (sem). the increase of modified polysaccharide and bioecolians? in the films favored their permeability to the water vapour and their hydration degree when in fis (ph = 6.8). in that way, the obtained film in the concentration 70:20:10, can prevent the premature release of the drug in the up git when applied to develop oral solid systems coating. besides, the presence of pect-tmft and bioecolians? can contribute to the specific membrane degradation by colonic microflora enzymes, making possible a modified release kinetics of drugs even with the existence of inter-individual variations of ph.
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