Surface characterization and dissolution properties of high amylose corn starch–pectin coatings

Thermal, Mechanical and Microstructures Properties of Cellulose Derivatives Films: A Comparative Study

“…It was observed that higher values of half height correspond to more roughness, independently of the biopolymer type. In accordance with Dimantov et al, 3 a higher roughness corresponds to non-homogeneous structures. From the film topographies, it was possible to corroborate differences in microstructure in the same sample, due to the different roughness observed in the film central or outlying regions.…”

“…2 An enteric cover should protect from the effect of severe conditions in the gastrointestinal tract, including the acid nature of the stomach (pH 1-2), the pH of 6.1-8 of the intestine and the presence of bile and pancreatic enzymes. 2,3 The pharmaceutical industry used various approaches for the development of colon-targeted drug delivery systems, one of them is: embedding in biodegradable matrices in which the matrices of polysaccharides are assumed to remain intact in the physiological environment of stomach and small intestine but once they reach in the colon, they are acted upon by the bacterial polysaccharidases and results in the degradation of the matrices. 4 In this sense, the use of diverse polysaccharides as pectin and their salts, also amylosa, 4 dextrin, guar, 5 hydroxylpropylmethylcellulose ftalato, hydroxylmethylcellulose, 6 quitosano, 7 shellac, 8 carboxylmethylcellulose, 9 acetate of cellulose ftalato, 10 inulina and cyclodextrins, among others, it has been investigated exploring their potential to be used in the liberation of drugs in the colon [11][12][13] and also the design of functional ingredients that should be present in the colon in enough quantity in order to exercise their beneficial effect, as the case of probiotic microorganisms.…”

Matrizes poliméricas reticuladas de alta amilose e pectina para liberação controlada de fármacos

“…Onde: %R é a porcentagem de recuperação, J máx é o ultimo ponto da fase de fluência e J min é o último ponto da fase de recuperação (DOLZ et al, 2008).…”

“…Essa mudança observada no padrão de difração de raios X das amostras com reticulante mostra a ocorrência de modificações físicas e químicas, indicando a alteração da rede tridimensional (DUMOULIN et al, 1998), modificações essas que podem ser atribuídas ao processo de reticulação utilizado nesse trabalho.…”

“…Esse comportamento pode ser explicado pelo aumento da solubilidade da pectina nesse pH (pH= 7,4), devido à ionização dos grupos carboxílicos, tornando assim a liberação do fármaco mais rápida para os comprimidos que apresentam maior proporção desse polímero (DESAI, 2005;DIMANTOV et al, 2004;LIU et al, 2003). O perfil de liberação apresentado pela amostra 11-4-2SR evidencia essa tendência de comportamento, uma vez que a mudança de pH promoveu um aumento abrupto do percentual de fármaco liberado (~60%).…”