Effect of Oppositely Charged Polymer and Dissolution Media on Rheology of Spray-Dried Ionic Complexes

Abstract

Abstract. The purpose of this research was to address the utility of rheological study in understanding the influence of oppositely charged polymers on release of naproxen sodium encapsulated in chitosan particles. The interaction between oppositely charged κ-carrageenan (κ-Ca) and chitosan leads to relatively higher gel strength, which is proportional to the ability to retard the drug release at acidic pH. The oscillatory tests within the linear viscoelastic range where the stress is proportional to the applied strain were performed on the hydrated sample matrices containing chitosan-naproxen sodium spraydried complexes and k-Ca or hydroxypropyl methylcellulose (HPMC) in various ratios. It was observed that the effect of pH change on the dynamic moduli in spray-dried complexes containing κ-Ca was much stronger than that with HPMC reflecting presence of strong ionic interaction between κ-Ca and chitosan. The combination of oppositely charged polymers in different ratios proved to be useful in modulating the rheological properties of the hydrated formulations and their release-retarding properties. Dynamic moduli can be used to measure gel strength and are significant for the interpretation of oral sustained release spray-dried complexes.

Formulation and in-Vivo Study of Ketoprofen Tablets Prepared Using Chitosan Interpolymer Complexes

“…Moreover, Bhise et al 47 found that, after compression of a mixture of naproxen sodiumloaded chitosan particles and κ-carrageenan into tablets, the interaction between oppositely charged κ-carrageenan and chitosan leads to relatively higher gel strength, which is proportional to the ability to retard the drug release at acidic pH.…”

Polímeros usados como sistemas de transporte de princípios ativos

“…É um polímero semelhante à celulose, apresentando grupos amina na posição C 2 em vez dos grupos hidroxilas. Os grupos aminas conferem ao polímero uma densidade de carga eletrostática elevada, tornando-o disponível para reações químicas e formação de sais [53] . Calvo et al [54] prepararam nanopartículas de quitosana, o qual é adequado para incorporar proteínas.…”

Influences of novel microwave drying on dissolution of new formulated naproxen sodium

“…4 The major factors that can inuence the drug dissolution rate are those that inuence the nature of the interaction of the drug with the dissolution medium and other drug constituents such as the polymer llers and binders. The inuencing factors include the pH and ionic strength of the dissolution medium, drug's ionic nature, [5][6][7] drug's physical and chemical properties, 8 drug-polymer structure 9 and drug formulation. 10 Many studies available in the literature have investigated the inuence of the above-mentioned factors on the dissolution kinetics of drugs from tablets.…”

“…11 Bhise et al showed that the pH of the medium has a strong inuence on the breakup tendency of the organic compounds of drugs into ionic species, which promote the drug release. 7 Poor solubility of orally-administrated drugs can affect the release of drugs and hence its absorption in blood vessels due to the resulting low concentration gradient. 5 Therefore, many studies in the literature have investigated the ways to enhance the dissolution rate of poorly soluble drugs.…”