Sodium montmorillonite/amine-containing drugs complexes: new insights on intercalated drugs arrangement into layered carrier material

PLoS One. 2015 Mar 24;10(3):e0121110. doi: 10.1371/journal.pone.0121110. eCollection 2015.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amines / analysis
  • Amines / chemistry*
  • Bentonite / analysis
  • Bentonite / chemistry*
  • Drug Carriers / analysis
  • Drug Carriers / chemistry*
  • Drug Delivery Systems / methods
  • Intercalating Agents / analysis
  • Intercalating Agents / chemistry*
  • Models, Molecular
  • Nanotechnology / methods

Substances

  • Amines
  • Drug Carriers
  • Intercalating Agents
  • Bentonite

Grants and funding

Financial support and fellowships from Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) were received for this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.