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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. [ABSTRACT FROM AUTHOR]

Nanotechnology has contributed to the creation of several products and industrial methods. Herein we tested the intercalation of biomaterials into inorganic nanolamellae as pharmaceutical excipients. These materials included sodium and alkylammonium montmorillonite, viscogel B8, ethylcellulose, and chitosan, and the intercalation results success was observed with ethylcellulose and viscogel B8. Thus this nanocomposite was tested with dapsone pills as a model in simulated gastric and enteral fluids and showed a close zero order type kinetics and a higher drug release retardation. This data suggests that this nanocomposite has potential not only for colon specific use but also for prolonged release systems coatings. [ABSTRACT FROM AUTHOR]

The preparation of new biocompatible polymer systems could accelerate processes underlying guided bone tissue regeneration (GBR) by acting as adjuvants. Here, different reaction conditions were investigated to engineer nanocomposites based on chitosan and sodium montimorilonite (Na-Mt) that can be used to generate biocompatible membranes. The goal was a balanced combination of flexibility and tensile strength for use in orthopedic and periodontal surgical procedures for improved GBR. The execution of different experimental protocols aimed to control the polymer intercalation process inside the Na-Mt lamellae, and to avoid their exfoliation, by varying its concentration while applying, at same time, ultrasonic energy as a pretreatment. To increase the therapeutic efficacy of the membranes formed, sodium alendronate was included in the compositions as well as plasticizers to optimize their mechanical and physical-chemical properties. All membranes were analyzed by powder x-ray diffraction, nuclear magnetic resonance, differential scanning calorimetry and thermogravimetric analysis, as well as high performance chromatography to characterize the sodium alendronate content. Surface roughness, water absorption (swelling) and tensile strength were evaluated by scanning electron microscope and profilometry. As a model for human osteoblasts, the proliferation of Saos-2 cells was measured by colorimetric assays and microscopy to assess the potential performance of the membranes in GBR. Membranes with improved mechanical and physical-chemical properties along with excellent biocompatibility could be generated from 33% sodium montmorillonite (w/w) intercalated with chitosan and containing sodium alendronate, glycerol (20% [w/w]) and Labrasol® (3% [w/w]) that also supported the induction of Saos-2 cell proliferation and differentiation, exhibiting potential to develop a novel biomaterial device for GBR [ABSTRACT FROM AUTHOR]

Photoprotective potential and biological consequences (mutagenic potential) of octyl-dimethyl- PABA ( ODP), titanium dioxide ( Ti O2), and montmorillonite ( MMT) upon ultraviolet B ( UVB) irradiation, alone and in different associations [physical mixtures ( PMs)], were evaluated using a Saccharomyces cerevisiae ogg1 mutant (deficient) strain. In addition, we developed and characterized a delaminated Ti O2-pillared MMT, called the Ti O2- MMT nanocomposite ( NC), which was also investigated in terms of its photoprotective and mutagenic potential. Overall, our results revealed an interesting Ti O2- MMT NC endowed with antimutagenic activity that can be associated to organic sunscreen molecule ( ODP) and still maintain its positive effect, whereas its respective PM is unable to grant antimutagenic protection against UVB. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:2539-2545, 2014 [ABSTRACT FROM AUTHOR]

• Montmorillonite (MMT) may play a very crucial role in modulating drug delivery of class II drugs of biopharmaceutical classification system, such as bromopride. • Bromopride was successfully intercalated in the sodium-MMT and the complex showed sustained release during performed assays. • This new bromopride sustained-release system showed an alternative to improve its pharmacological performance in therapeutic applications. • Molecular dynamics simulations showed the bromopride interactions to the montmorillonite layer. The drug delivery systems are an important strategy of pharmaceutical technology to modulate undesirable properties, increasing efficacy, and reducing the side effects of active pharmaceutical ingredients (API). The sustained release is a type of controlled-release system that provides a suitable drug level in the blood through a slow release rate. An interesting alternative to achieve a controlled release is the application of carrier materials such as polymers, cyclodextrins, and clays. Sodium montmorillonite (Na-MMT) is a biocompatible natural clay that allows the insertion of organic compounds in interlamellar space, owing to its high cation exchange capacity and large internal surface area. Bromopride (BPD) is an aminated compound with antiemetic properties classified as class II (low solubility, high permeability) of the Biopharmaceutical Classification System (BCS). Herein, the aim of the study was the development and investigation of a drug delivery system formed by intercalation of BPD with Na-MMT. The results indicate the successful intercalation of this API with the lamellar silicate, meanwhile, there was no evidence of BPD intercalation in organic montmorillonite. The Na-MMT/BPD molecular complex exhibits a sustained release in performed assays. Molecular dynamics simulations suggested that BPD molecules interact with the montmorillonite layer through ion-dipole interactions and also between BPD molecules, forming hydrogen bonds web into montmorillonite interlayer space. The new drug delivery system showed an alternative to achieve the BPD sustained release, which may improve its pharmacological performance in therapeutic applications. [Display omitted] [ABSTRACT FROM AUTHOR]