Adsolubilization of drugs onto natural clinoptilolite modified by adsorption of cationic surfactants

Zeolites as Ingredients of Medicinal Products

Development of new medicinal products for particular therapeutic treatment or for better manipulations with better quality and less side effects are possible as a result of advanced inorganic and organic materials application, among which zeolites, due to their properties and versatility, have been gaining attention. This paper is an overview of the development in the use of zeolite materials and their composites and modifications as medicinal products for several purposes such as active agents, carriers, for topical treatments, oral formulations, anticancer, the composition of theragnostic systems, vaccines, parenteral dosage forms, tissue engineering, etc. The objective of this review is to explore the main properties of zeolites and associate them with their drug interaction, mainly addressing the advances and studies related to the use of zeolites for different types of treatments due to their zeolite characteristics such as molecule storage capacity, physical and chemical stability, cation exchange capacity, and possibility of functionalization. The use of computational tools to predict the drug-zeolite interaction is also explored. As conclusion was possible to realize the possibilities and versatility of zeolite applications as being able to act in several aspects of medicinal products.

Performance of HDTMA-Br-Modified Indonesian Zeolite as a Drug Carrier Candidate for Diclofenac Sodium

Diclofenac sodium is a non-steroidal anti-inflammatory drug with a relatively short release time. This short release time promotes a more frequent drug consumption and could lead to side effects in the stomach, e.g., gastrointestinal disorders, gastrointestinal bleeding, and gastric ulcers. A drug delivery system with a slow-release activity is one of the promising technologies to control the drug amount released to the stomach. A surfactant-modified natural zeolite as a carrier for diclofenac sodium has been used in this study. This study focused on the preparation, characterization, and slow-release performance of HDTMA-modified natural zeolite as a carrier for diclofenac sodium. The zeolite underwent chemical and physical activation, as well as milling prior to use. It was proven that the zeolite used was dominated by mordenite and clinoptilolite with high stability properties towards acid treatments, as indicated by the XRD patterns. A modification of the zeolite surface using HDTMABr was also successfully performed, indicated by the appearance of peaks at wavenumbers of 2923.05 cm-1 and 2853.39 cm-1 (symmetrical and asymmetrical CH2 strains of HDTMA molecules, respectively) in the FTIR spectra. The synthesized HDTMA-modified natural zeolite also showed an excellent surface property such as surface area, pore-volume, and size, as indicated by the BET-BJH isotherms on the nitrogen adsorption. The slow-release performance of the zeolite-based drug delivery system was studied by investigating the adsorption-desorption behavior of HDTMA-modified zeolite towards diclofenac sodium. The HDTMA-modified zeolite adsorbed the diclofenac sodium of 54.01% at a pH of 7.5, the contact time of 60 min, and the initial concentration of 100 ppm. The adsorbed diclofenac sodium of 73.95% could be released from the HDTMA-modified adsorbent for 8 h, mimicking the time length of drug metabolism in the human body.

One-pot synthesis of the organomodified layered double hydroxides - glibenclamide biocompatible nanoparticles

In this work, synthesis of sodium dodecyl sulfate (SDS) organomodified LDH Zn₂Al carrying glibenclamide (GLIB) was performed in one step and in one-pot to obtain nanoparticles (NP). XRD data showed GLIB adsolubilization (d = 14.03 Å) and NP coating with Eudragit L100®. In addition, thermal and XRD data showed exfoliated/intercalated nanocomposite for NP S5 (LDH associated with SDS and Eudragit L100®). LDH organophilization and GLIB intercalation reduced surface area (SBET 23.58 m²/g) and NP size (469 nm). In addition, the change in zeta potential (-35.5 ζ) relative to pristine LDH (SBET 41.34 m²/g, 688.8 nm and +14 ζ) indicated that LDH functionalization seems an appropriate approach to produce NP with greater colloidal stability and enhanced functionality. The zinc release data from the LDH matrix (2.96 % ±0.002 ppm) showed the effectiveness of the coating in acid medium (pH 1.2) and the release data from GLIB showed the kinetics of release of zero order with release in simulated intestinal medium (pH 7.4) of 88 % and 73 % (24 h) for uncoated and coated NP, respectively. All NP were considered biocompatible in the WST-1 assay on BALB 3T3 fibroblast strains making these NP promising therapeutically.

Insights into the Interactions of Sulfamethoxazole with Organized Assemblies of Ionic and Nonionic Surfactants

This work reports the physicochemical behavior of antibiotic drug sulfamethoxazole (SMX) in the presence of different surfactants, viz., cetyl trimethyl ammonium bromide (CTAB), dodecyl trimethyl ammonium bromide, didodecyl dimethyl ammonium bromide, sodium dodecyl sulfate, sodium deoxycholate, Tween 80, and Tween 20. The drug-surfactant systems were studied by UV-visible and fluorescence spectroscopies to assess the binding constants ( K_b), partition coefficient ( K_x), free energy of partition (Δ G_p), aggregation number ( N_agg), and quenching constant ( K_SV). Solubilization studies were carried out to understand the encapsulation efficiency of the system, which was found to increase as a function of CTAB concentration. Surface tension measurements enabled us to determine the change in critical micelle concentration as well as to calculate the variation in surface parameters of surfactant in the presence of drug, viz., surface pressure (π), surface excess concentration (γ_max), and minimum area ( A_min). In addition, UV-visible, fluorescence, and circular dichroism studies were carried out to check the effects of surfactant-based SMX formulation on serum proteins.

Design and characterization of chitosan/zeolite composite films--Effect of zeolite type and zeolite dose on the film properties

Chitosan films can be used as wound dressings for the treatment of chronic wounds and severe burns. The antimicrobial properties of these films may be enhanced by the addition of silver. Despite the antimicrobial activity of silver, several studies have reported the cytotoxicity as a factor limiting its biomedical applications. This problem may, however, be circumvented by the provision of sustained release of silver. Silver zeolites can be used as drug delivery platforms to extend the release of silver. The objective of this study was to evaluate the addition of clinoptilolite and A-type zeolites in chitosan films. Sodium zeolites were initially subjected to ion-exchange in a batch reactor. Films were prepared by casting technique using a 2% w/w chitosan solution and two zeolite doses (0.1 or 0.2% w/w). Films were characterized by thermal analysis, color analysis, scanning electron microscopy, X-ray diffraction, and water vapor permeation. The results showed that films present potential for application as dressing. The water vapor permeability is one of the main properties in wound dressings, the best results were obtained for A-type zeolite/chitosan films, which presented a brief reduction of this property in relation to zeolite-free chitosan film. On the other hand, the films containing clinoptilolite showed lower water vapor permeation, which may be also explained by the best distribution of the particles into the polymer which also promoted greater thermal resistance.