Tomaž Čendak

National Institute of Chemistry · Department of Inorganic Chemistry and Technology

Three porous aluminium benzene-1,3,5-tricarboxylates MIL-96(Al), MIL-100(Al) and MIL-110(Al) materials were studied for their hydrothermal stability. The 40-cycles water vapour sorption experiments for the three samples were performed by varying the temperature between 40 and 140 °C at 75% relative humidity to simulate working conditions for materi...

An investigation of hydrotalcite-derived ternary Mg-Al-Ce oxides as catalysts for vapour phase condensation of ethanol to 1-butanol in a flow reactor under atmospheric pressure was carried out. The Mg-Al-Ce oxide systems with Mg/(Al + Ce) ratio from 1 to 4 were synthesized and characterized by XRD, SEM, NMR, and XPS. The study of acid-base characte...

Polyurea-crosslinked alginate (X-M-alginate; M: Co, Ni, Cu) aerogels, prepared from the corresponding M-alginate wet-gels and the aromatic triisocyanate Desmodur RE, are precursors for metal- and nitrogen-doped carbon (X-M-C) aerogels.

The prospects of using cerium as a modifying additive of Mg–Al hydrotalcite-derived oxide system have been estimated by low-temperature nitrogen ad(de)sorption, X-ray diffraction, scanning electron microscopy, 1H and 27Al solid-state nuclear magnetic resonance (NMR), X-ray photoelectron and UV–Vis diffuse reflectance spectroscopy techniques. The ef...

Polyurea-crosslinked calcium alginate (X-Ca-alginate) and chitosan (X-chitosan) aerogel beads have been prepared via reaction of an aliphatic triisocyanate (Desmodur N3300) with the –OH groups of calcium alginate or the –NH2 groups of chitosan preformed wet gels, forming surface urethane or urea groups, respectively, and the subsequent formation of...

High level radioactive actinides are produced as a side product in reprocessing spent nuclear fuel, for which safe long-term-inert immobilizer matrices are needed. Borosilicate glasses are of great potential amongst the candidates of suitable inert materials for radioactive waste immobilization. Understanding the effects of actinide addition to a b...

We have investigated the perturbation of influenza A M2TM in DMPC bilayers. We have shown that (a) DSC and SAXS detect changes in membrane organization caused by small changes (micromolar) in M2TM or aminoadamantane concentration and aminoadamantane structure, by comparison of amantadine and spiro[pyrrolidine-2,2′-adamantane] (AK13), (b) that WAXS...

The synthesis and characterization of the multicomponent crystals formed by salicylic acid and 1,2-phenylenediamine (a diarylamine) are reported. The crystals are in the salt rather than cocrystal form, as witnessed by X-ray photoelectron spectroscopy, solid-state NMR, and infrared spectroscopy. 1H double-quantum–single-quantum NMR was pivotal in c...

The successive vapour phase condensation of ethanol and 1-butanol (via Guerbet reaction) in a flow reactor under atmospheric pressure was studied over catalytic Mg-Al oxide compositions. Wherein the vapour phase condensation of 1-butanol to 2-ethyl-1-hexanol in flow has been investigated for the first time. The acid/base capacity ratio, which is deter...

The investigation and observations made for the M2TM, excess aminoadamantane ligands in DMPC were made using the simpler version of biophysical methods including SDC, SAXS and WAXS, MD simulations and ssNMR. 1H, 31P ssNMR and MD simulations, showed that M2TM in apo form or drug-bound form span the membrane interacting strongly with lipid acyl chain...

Typical zeolite synthesis reaction mixture involves framework atom source, solvent, mineraliser, and structure directing agent. However, these components often have a dual function, and their impact on the nucleation/crystallization process is difficult to be established straightforwardly. The present study deals with the structure directing effect...

Human remains from the skeletal collection of the UNESCO world heritage site of Sedlec (Czechia) have been investigated with ¹H, ³¹P and ¹³C magic‐angle‐spinning nuclear magnetic resonance spectroscopy. The quantitative description of the component of the phosphorus signal attributed to the external amorphous hydrated layer of the mineral apatite p...

Hydrogen Bonds (HB) play a key role in the supramolecular arrangement of crystalline solids and, although they have been extensively studied, the influence of their strength and geometry on crystal packing remains poorly understood. Here we describe the crystal structures of two novel protic gabapentin (GBP) pharmaceutical salts prepared with the c...

The wealth of site‐selective structural information on CO2 speciation, obtained by spectroscopic techniques, is often hampered by the lack of easy‐to‐control synthetic routes. Herein, an alternative experimental protocol that relies on the high sensitivity of 13C chemical shift anisotropy (CSA) tensors to proton‐transfer, is presented to unambiguou...

The separation of CO2/CH4 gas mixtures on mesoporous SBA-15 functionalized with primary, secondary and tertiary amines, and a diamine (primary and secondary), was studied by gas adsorption, solid state nuclear magnetic resonance (ssNMR) and electronic structure density functional theory (DFT) techniques to evaluate the possible application of amine...

HKUST-1 metal-organic framework was crystallized in the NH2-modified mesostructured silica FDU-12 in order to improve its structural stability upon water exposure. In-depth structural characterization studies of the designed composite confirmed successful formation of MOF phase within the ordered spherical mesopores of the silica matrix. In spite o...

Two-dimensional (2D) solid-state nuclear magnetic resonance (NMR) experiments on samples loaded with 13C-labeled CO2, “under controlled partial pressures”, have been performed in this work, revealing unprecedented structural details about the formation of CO2 adducts from its reaction with various amine-functionalized SBA-15 containing amines havin...

Interactions of drug molecules embedded within the pores of drug-delivery matrices significantly influence the drug-release rate and profile. In this Article, we used solid-state NMR experiments to inspect the interactions of indomethacin drug and tetrahydrofuran solvent molecules within mesoporous MIL-101 metal-organic framework materials. MIL-101...

Zinc trimesate material with high hydrothermal stability was studied for water adsorption/desorption dynamics, and we explained the reason for material's stability in water. A zinc trimesate Zn-2(BTC)(OH)-(H2O)center dot 1.67H(2)O with the three-dimensional framework contains [Zn2O6(OH)(H2O)] chains with ZnO2(OH)(2) tetrahedra and ZnO4(OH)-(H2O) oc...

The present work describes the drug:membrane interactions and a drug delivery system of the novel potent AT1 blocker BV6. This designed analog has most of the pharmacological segments of losartan and an additional biphenyltetrazole moiety resulting in increased lipophilicity. We found that BV6:membrane interactions lead to compact bilayers that may...

The structural properties of the mesoscopically confined drug and drug–drug and drug–matrix interactions were investigated in model drug-delivery systems prepared from nonfunctionalized and functionalized SBA-15 mesoporous silicate matrices, loaded with different amounts of indomethacin molecules. 1H MAS and 1H–13C CPMAS NMR spectroscopy indicated...