VSE knjižnice (vzajemna bibliografsko-kataložna baza podatkov COBIB.SI)
  • Structural and dynamical properties of indomethacin molecules embedded within the mesopores of silicates and metal-organic framework materials : a solid-state NMR view
    Mali, Gregor, 1971- ...
    The structural properties of the mesoscopically confined drug, and drug-drug and drug-matrix interactions were investigated in model drug-delivery systems prepared from MCM-41 and SBA-15 mesoporous ... silicate matrices, and Cr-MIL-101, Fe-MIL-101, and Al-MIL-101 metal-organic frameworks, loaded with different amounts of indomethacin molecules. 1H MAS and 1H-13C CPMAS NMR spectra indicated that only when the concentration of indomethacin within the mesopores becomes sufficiently high, hydrogen bonds between the drug molecules become abundant. Nitrogen sorption analysis and comparison of 1H spin-lattice relaxation times in progressively loaded mesoporous matrices suggested that at low loading concentrations indomethacin forms layers on the walls of the mesopores, and that at moderate or high loading concentrations rigid nanoparticles that extend throughout the entire mesopore cross-section are formed. Variable-temperature 1H spin-lattice relaxation measurements showed that the mesoscopically confined indomethacin is significantly different from the bulk amorphous indomethacin. It does not become rubbery and it exhibits a solid-solid transition that is similar to the phase transition of the crystalline indomethacin solvate. The obtained results are important for the understanding of the release kinetics and for the estimation of the total amount of the released drug from the drug-delivery system.
    Vrsta gradiva - prispevek na konferenci
    Leto - 2012
    Jezik - angleški
    COBISS.SI-ID - 5046554