Release of cationic drugs from loaded clay minerals

Nanostructured Materials Research Group of Hungarian Academy of Sciences, 6720 Szeged, Aradi vértanúk tere 1, Hungary HU
Colloid and Polymer Science (Impact Factor: 2.16). 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

  • [Show abstract] [Hide abstract]
    ABSTRACT: To evaluate the cytotoxic effect and the mechanism of the apoptosis of oligo(styrene-co-acrylonitrile)-modified montmorillonite (PSAN-MMT), the present study is focused on the involvement of anti-proliferation, lactate dehydrogenase release, apoptosis level, caspase 3 activity, transcriptional activity of apoptosis-related gene and apoptosis-related protein and mRNA level. Non-cytotoxic montmorillonite (MMT) incubated cells were used as control. Little cytotoxicity was observed in PSAN-MMT treated cells, and lower level of apoptosis was induced by PSAN-MMT when cells were incubated with high montmorillonite content (1 g/L). The apoptosis seemed to follow a transcription-dependent route by activating proapoptotic genes such as p53 and p21. The modified MMT could be a promising candidate of biosafety controlled-release carrier for large drug molecules and for gene delivery.Research Highlights► Montmorillonite modified by oligo(styrene-co-acrylonitrile) (PSAN-MMT). ► PSAN-MMT with little cytotoxicity and low level of apoptosis for the cells. ► The apoptosis followed on a transcription route by activating proapoptotic genes. ► PSAN-MMT as a biosafety controlled-release carrier for drugs and gene delivery.
    Applied Clay Science 01/2011; 51(3):214-219. · 2.34 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The objective of this work was to illustrate the suitability of montmorillonite (MMT) as a drug delivery carrier, by developing a new clay-drug composite of ranitidine hydrochloride (RT) intercalated in MMT. The MMT-RT composite was prepared by ion-exchange process. X-ray diffraction and Fourier transform infrared spectra were employed to confirm the intercalation of RT in the MMT interlayers. The prepared MMT-RT hybrid was coated with cationic polymer Eudragit E-100 by oil-in-water solvent evaporation method. The release processes of RT from MMT-RT and MMT-RT/Eudragit E-100 were monitored under in vitro condition in the gastric fluid. X-ray diffraction and Fourier transform infrared spectra analysis indicated the intercalation of RT molecules within the clay lattice. The in vitro release studies showed that MMT-RT released RT in a controlled manner. In the case of MMT-RT/Eudragit E-100, both the release rate and the release percentages noticeably increased in the presence of Eudragit E-100, because of its effective exchange with intercalated RT molecules. The release kinetics followed parabolic diffusion mechanism. MMT has great potential as a drug delivery carrier with various scenarios. The dosage of the MMT-RT/Eudragit E-100 can be in the tablet form. The hybrid material and polymer-coated hybrids are microparticles.
    Drug Development and Industrial Pharmacy 09/2010; 36(9):1046-53. · 1.54 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Anionic surfactant sodium dodecyl sulfate (SDS), cationic surfactant cetyl trimethyl ammonium bromide (CTAB) and acrylic acid (AA) were introduced as molecular models to study the interaction between montmorillonite and organic molecules with different charge or chain length. The compounds were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and 13C nuclear magnetic resonance (13C NMR). The results show organic anion could interact strongly with montmorillonite, even the molecules could intercalate into the layers of MMT.
    Journal of Wuhan University of Technology-Mater Sci Ed 28(1). · 0.48 Impact Factor