Investigation of pantoprazole loading and release from a magnetic-coated chitosan-modified zirconium-based metal-organic framework (MOF) as a nanocarrier in targeted drug delivery systems.

This study reports a novel magnetic and porous nanocomposite, Fe3O4@CS@UIO-66-NH2(Zr), developed by growing a zirconium-based metal-organic framework on magnetite-chitosan. It is designed for targeted and delayed pantoprazole delivery, the nanocomposite exhibits pH-sensitive behavior and functions as an efficient nanocarrier. The synthesis process involved coating magnetite nanoparticles with chitosan, followed by the growth of UIO-66-NH2(Zr) on the coated nanoparticles. The nanocomposite demonstrated high drug loading efficiency (DLE) in acetate buffer (pH 5.0) and deionized water, with loading percentages of 79% and 75%, respectively, within 48 hours. The corresponding drug loading content (DLC) was approximately 14% and 10%. The Freundlich and Langmuir models accurately described the multilayer adsorption behavior of pantoprazole on the nanocomposite's active sites. BET and EDX-map analyses confirmed that the drug was loaded into the nanocomposite's pores and uniformly adsorbed on its surface. The drug release kinetics were best described by the pseudo-second-order model. Due to its porosity, magnetic properties, and favorable drug loading characteristics, the Fe3O4@CS@UIO-66-NH2(Zr) nanocomposite shows potential as an efficient targeted drug delivery system for in vivo applications.

Direct photochemical route to azoxybenzenes via nitroarene homocoupling.

We report on a direct photochemical method for the one-pot, catalyst- and additive-free synthesis of azoxybenzene and substituted azoxy derivatives from nitrobenzene building blocks. This reaction is conducted at room temperature and under air, and can be applied to substrates with a wide range of substituents. Yields of products derived from para- and meta-substituted nitrobenzenes are typically good, while sterically encumbered ortho-substituted substrates are not as fruitful. Photochemical Wallach rearrangement of generated azoxybenzenes to ortho-hydroxyazoxybenzenes was observed in some cases, most markedly in selected ortho-halogenated nitrobenzenes. Overall, this method provides an efficient, green pathway to highly value-added azoxybenzene products.