Layered Mg-Al hydrotalcite in the chloride form, Mg0.67Al0.33(OH)2Cl0.33 • 0.6 H20, was used as a host to intercalate diclofenac, a non-steroidal antiiflammatory drug. The intercalation compound was prepared by Cl-/diclofenac anionic-exchange. All hydrotalcite Cl- ions were completely exchanged by the diclofenac anions with a consequent expansion of the interlayer distance from 0.78 to 2.36 nm. In vitro drug release from the intercalation compound, containing 55% w/w of drug, was performed in simulated intestinal fluid at pH 7.5 according to USP XX and in a pH 7.0 solution designed to mimic the small intestine condition. Drug release at pH 7.5, attributed to exchange of diclofenac ions with phosphates of the medium, was almost complete whereas at pH 7.0 the drug release from the intercalate was about 70%.
Intercalation Compounds of Hydrotalcite-like Anionic Clays With Anti-inflammatory Agents, II: Uptake of Diclofenac for a Controlled Release Formulation
AMBROGI, Valeria;FARDELLA, Giuseppe;GRANDOLINI, Giuliano;PERIOLI, Luana;TIRALTI, Maria Cristina
2002
Abstract
Layered Mg-Al hydrotalcite in the chloride form, Mg0.67Al0.33(OH)2Cl0.33 • 0.6 H20, was used as a host to intercalate diclofenac, a non-steroidal antiiflammatory drug. The intercalation compound was prepared by Cl-/diclofenac anionic-exchange. All hydrotalcite Cl- ions were completely exchanged by the diclofenac anions with a consequent expansion of the interlayer distance from 0.78 to 2.36 nm. In vitro drug release from the intercalation compound, containing 55% w/w of drug, was performed in simulated intestinal fluid at pH 7.5 according to USP XX and in a pH 7.0 solution designed to mimic the small intestine condition. Drug release at pH 7.5, attributed to exchange of diclofenac ions with phosphates of the medium, was almost complete whereas at pH 7.0 the drug release from the intercalate was about 70%.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
