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.

Thermodynamics of adduct formation of cobalt(II) tetraaza Schiff base complexes with organotin(IV)trichlorides.

UV-Vis. spectrophotometric study of the adduct formation of organotin(IV)trichlorides i.e. PhSnCl3 and MeSnCl3 as acceptors with Co(II) tetraaza complexes, such as [Co(ampen)] [N,N'-ethylenebis-(o-amino-α-phenylbenzylideneiminato)cobalt(II)], [Co(campen)] [N,N'-ethylenebis-(5-chloro-o-amino-α-phenylbenzylideneiminato)cobalt(II)], [Co(amaen)] [N,N'-ethylenebis-(o-amino-α-methylbenzylideneiminato)cobalt(II)], [Co(amppn)] [N,N'-propylene bis-(5-chloro-o-amino-α-phenylbenzylideneiminato)cobalt(II)] and [Co(camppn)] [N,N'-propylenebis-(5-chloro-o-amino-α-phenylbenzylideneiminato)cobalt(II)] as donors were studied spectrophotometrically under N2 atmosphere and in N,N'-dimethylformamide solvent. The formation constants and thermodynamic parameters were measured using spectrophotometric titration of adduct formation at various temperatures. The trend of the adduct formations of the cobalt(II) tetraaza complexes with a given organotintrichloride acceptor decreases as follow: [Co(amaen)]>[Co(amppn)]>[Co(ampen)]>[Co(camppn)]>[Co(campen)]. The trend of the formation constants for the studied organotintrichlorides with a given cobalt(II) tetraaza complexes is as follow: PhSnCl3>MeSnCl3.