Article

Release of cationic drugs from loaded clay minerals

University of Szeged, Algyő, Csongrád, Hungary
Colloid and Polymer Science (Impact Factor: 2.41). 11/2001; 279(12):1177-1182. DOI: 10.1007/s003960100527

ABSTRACT The adsorption of promethazine chloride [10-(2-dimethylammonium propyl) fenothiazine chloride] and buformin hydrochloride
(1-butylbiguanidine chloride) on montmorillonite was studied in previous work. The present article focuses on the desorption
of these molecules from their organocomplexes in a medium of artificial intestinal juice (pH 7.0 ± 0.1) at the temperature
of the human body (37 ± 0.5 °C). The desorption was investigated by kinetic studies, basal spacing measurements and Fourier
transform IR studies. Important quantitative differences were observed: buformin, which adsorbed in a monolayer coverage,
exhibited a very high desorption rate, whereas promethazine formed a pseudotrilayer arrangement and showed a lower dissolution
rate.

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