Sodium Montmorillonite/Amine-Containing Drugs Complexes: New Insights on Intercalated Drugs Arrangement into Layered Carrier Material

Abstract

Layered drug delivery carriers are current targets of nanotechnology studies since they are able to accommodate pharmacologically active substances and are effective at modulating drug release. Sodium montmorillonite (Na-MMT) is a clay that has suitable properties for developing new pharmaceutical materials due to its high degree of surface area and high capacity for cation exchange. Therefore Na-MMT is a versatile material for the preparation of new drug delivery systems, especially for slow release of protonable drugs. Herein, we describe the intercalation of several amine-containing drugs with Na-MMT so we can derive a better understanding of how these drugs molecules interact with and distribute throughout the Na-MMT interlayer space. Therefore, for this purpose nine sodium montmorillonite/amine-containing drugs complexes (Na-MMT/drug) were prepared and characterized. In addition, the physicochemical properties of the drugs molecules in combination with different experimental conditions were assessed to determine how these factors influenced experimental outcomes (e.g. increase of the interlayer spacing versus drugs arrangement and orientation). We also performed a molecular modeling study of these amine-containing drugs associated with different Na-MMT/drug complex models to analyze the orientation and arrangement of the drugs molecules in the complexes studied. Six amine-containing drugs (rivastigmine, doxazosin, 5-fluorouracil, chlorhexidine, dapsone, nystatin) were found to successfully intercalate Na-MMT. These findings provide important insights on the interlayer aspect of the molecular systems formed and may contribute to produce more efficient drug delivery nanosystems.

Decontamination of T-2 Toxin in Maize by Modified Montmorillonite Clay

“…Montmorillonite clay has pharmaceutical applications where it serves as an excipient in drugs for oral or topical use [21]. The cytotoxicity of montmorillonite clay is low both in vitro and in vivo [22].…”

Recent developments in the use of organic–inorganic nanohybrids for drug delivery

“…In fact, this mechanism along with the remarkable swelling capability (Panahi, Gharekhani, Hamishehkar, Zakeri‐milani, & Gharekhani, ) and adsorptivity (Joshi, Kevadiya, Mody, & Bajaj, ) of clay minerals have paved the basis for extensive use of clay‐based hybrid materials to be explored for their potential use in extended release systems (Jain & Datta, ), site‐specific release systems (Mahkam, Rafi, & Gheshlaghi, ), and drug solubility improvement systems (Zheng, Luan, Wang, Xi, & Yao, ). Enhanced properties such as increased surface area, porosity, and ion exchange capacity may improve clay–drug affinity, and enable extended release of drugs (Bello, Junior, Vieira, Dias, & De, ). Required properties of natural clays have been further improved using thermal and chemical treatments (Q. Wang, Zhang, Zheng, & Wang, ) and polymeric additives.…”

The Use of Some Clay Minerals as Natural Resources for Drug Carrier Applications

“…According to the British, European and United States Pharmacopeias, the use of montmorillonite is mainly as auxiliary material in the pharmaceutical industry for topical or oral dosage forms. MMT indeed, thanks to its physicochemical properties (such as high swelling ratio), can intercalate active compounds between the layers generating a host for oral or topical drug delivery [54,55,56,57,58,59,60,61,62,63,64,65,66]. For montmorillonite topical use, it possesses beneficial effects in cosmetic and dermatological applications (paleotherapy and geotherapy) [1,67].…”