[en] The development of drug delivery nano-carriers is emerging as a promising therapeutic tool to transport anticancer agents to tumors. In this contribution, preparation of nanoparticles (NPs) highly loaded with cisplatin using the bio-inspired hybrid nucleoside-lipids has been reported. The construction of these NPs using a 'layer-by-layer' approach allows surface functionalization with polyethylene glycol and targeting moieties. Uridine moieties were pegylated for folic acid (FA) functionalization to render specificity for active targeting. The uridine moieties at the surface of the nanoparticle act as ligands for ^99mTc radiolabeling, whereas the lipid chains maintain the structure of the nanoparticle. In vitro, these hybrid NPs are stable and actively internalize in two different cell lines over expressing the folic acid receptor. In vivo scintigraphy shows that nucleo-lipid functionalized NPs notably improved the pharmacokinetic profile of cisplatin (enhanced blood circulation time) and accumulated in the tumor xenografted mice model. (authors)

[en] Three novel phosphine oxide-based conjugated microporous polymers TEPO-1, TEPO-2 and TEPO-3 are designed and synthesized, which are constructed using the phosphine-based building unit tris-(4-ethynyl-phenyl)phosphine oxide with linkers tris(4-ethynyl-phenyl)phosphine oxide, triphenylphosphine oxide and tri(thiophen-2-yl)phosphine oxide via Sonogashira-Hagihara homo-coupling or cross coupling condensation reaction. The adsorption isotherms of N₂ reveal that the Brunauer-Emmett-Teller (BET) specific surface areas of TEPO-1, TEPO-2 and TEPO-3 are 485 m² g^-1, 534 m² g^-1 and 592 m² g^-1, respectively. However, these three polymers have strong affinity for CO₂, which exhibit relatively high sorption abilities for CO₂ (273 K/1.0 bar: 6.52 wt%, 7.62 wt%, and 8.40 wt%). Meanwhile, the TEPOs demonstrate ultrahigh hydrogen uptake and outstanding CO₂/CH₄ selectivity compared to analogous materials with similar BET surface areas using C, Si and N as the nodes. This work reveals clearly that the gas uptake capacity of material is highly dependent on the length of the rigid skeleton and the modification of functional groups in the monomer structure. (authors)

[en] A methyl-modified metal-organic framework (m-TiBDC) shows significantly enhanced hydro-stability than unmodified TiBDC, and thus can maintain almost intact CO₂ gas adsorption capacity even after its immersion in water for 2 h while TiBDC does not. (authors)

[en] The interaction of carbon monoxide with organo-actinides has recently been shown experimentally, particularly by Cloke and co-workers, to result in coupling to give the oligomeric anions C_nO_n^2- (n = 2, 3, 4). In order to model possible intermediates in reactions of this type, we have used density functional theory to explore the systems (C₈H₈)Th(CO)_n (n = 1 to 5) and (C₈H₈)₂Th₂(CO)_n (n = 2 to 7) related to the known 'thorocene', (η₈ -C₈H₈)₂Th. Thorium was chosen as the actinide for this work since its chemistry almost entirely involves the single diamagnetic +4 oxidation state. All of the binuclear (C₈H₈)₂Th₂(CO)_n structures found in this work have long Th-Th distances ranging from 4.4 to 5.0 Angstroms suggesting the absence of direct Th-Th bonds. Two (C₈H₈)₂Th₂(CO)₂ isomers of similar energies in which the two CO groups have coupled to form trans and cis isomers of a bridging η⁴ -μ-C₂O₂ ligand are low energy structures. These bridging η⁴-μ-C₂O₂ ligands exhibit ultralow ν(CO) frequencies around 1000 cm^-1 indicating strong back donation of thorium d and f electrons into C-O antibonding orbitals. Most of the carbonyl richer (C₈H₈)₂Th₂(CO)_n (n = 3 to 7) structures are derived from one of these basic (C₈H₈)₂Th₂(CO)₂ structures by addition of terminal CO groups. An exception is the lowest energy (C₈H₈)₂Th₂(CO)₄ structure which has C_4v symmetry with four equivalent separate ν² -μ-CO groups bridging the thorium atoms. The thermochemistry of these systems suggest (C₈H₈)Th(CO)₄ and (C₈H₈)₂Th₂(CO)_n (n = 2, 4) to be the most promising synthetic objectives, which are potentially obtainable by reductive carbonylation of the known (C₈H₈)ThCl₂. (authors)

[en] A 'bimodal' or upper- and lower-rim functionalized 'calix-crown-5' reported herein was unexpectedly formed preferentially in a cone conformation. This was confirmed both by NMR spectroscopy and by single-crystal X-ray crystallography. The thioacetate functionalities on the new calix-crown-5 enabled it to form stable SAMs on the Au surface of a micro-cantilever, and a sensitive cesium ion sensor. (authors)

[en] As synthetic lanthanide monophosphate (monazite) ceramics are able to be a good nuclear waste disposal material, properties of thorium monophosphate for the disposal of radioactive wastes was done. Through chemical reaction involving thorium oxide (or a thorium salt such as ThCl₄ or Th(NO₃)₄, 4H₂O) and a phosphate compound (BPO₄, NH₄H₂PO₄ or concentrated phosphonic acid H₃PO₄) a systematic investigation of the (ThO₂--P₂O₅) system has confirmed the existence of compounds with 1:2, 1:1, 3:2, and 3:1 ThO₂:P₂O₅ ratio, the corresponding Th₃ (PO₄)₄ compound exists in a low-and a high-temperature form. The conversion temperature is 1250 deg C. The X-ray pattern and physico-chemical properties of Th₃ (PO₄)₄ low-temperature form are presented. (authors). 35 refs., 10 figs., 4 tabs

[en] The structure of Li Zn B O₃ obtained by low temperature hydrothermal reaction has been determined previously in single crystals. We calculated the crystallographic cell of the phases obtained by solid-state reaction without melting by indexing their X-ray powder diffraction patterns. We found evidence that the structure of Li Zn B O₃ depends on the preparation method. The two structures found are monoclinic probably with the same Li-Zn cationic disorder, as evidence by vibrational behavior. The cell parameters for the phase prepared at high temperature are a = 7.9286(6), b = 5.0934(3), c 6.1464(5) A, β = 104.3(5)deg., Z = 4. The magnesium and cobalt compounds are isomorphous and form a total solid solution. Their monoclinic cells is not related to the cells of the zinc derivative. The parameters of the unit cell are a = 9.9155(8), b = 8.88847(11), c = 5.1577(4) A, β 91.231(8)deg., Z = 8 for the magnesium compound and a = 10.1100(7), b 8.8518(8), c = 5.1311(6) A, β = 91.358(7)deg., Z = 8 for the cobalt compound. The lithium cobalt borate is not very thermally stable and it is best synthesized by a two-step procedure. The effect of the lithium isotopic substitution on the vibrational frequencies shows that this cation is in tetrahedral coordination in all the phases. (authors). 6 refs., 3 figs., 5 tabs

[en] Treatment of the organometallic uranium hydride (C₅H₄SiMe₃)₃UH (1) with carbon dioxide afforded the formate derivative (C₅H₄SiMe₃)₃UOCHO which further reacts with (1) to give the dioxymethylene compound (C₅H₄SiMe₃)₃UOCH₂OU(C₅H₄SiMe₃)₃

[en] Willem Verboom, associate professor of organic chemistry at the University of Twente, The Netherlands, considers some of the latest advances in separating highly radioactive components of nuclear waste. (author)

[en] The solid-state behaviour of 2-chloro-4-nitrobenzoic ( 2c4n) acid has been reinvestigated. Infrared spectra, differential scanning calorimetry (DSC), and thermomicroscopy investigations as well as X-ray powder patterns for two modifications of the substance are described. Modification II is the thermodynamically stable crystal form from absolute zero to its transition point which occurs at approximately 97 C according to the DSC analysis. Above that temperature, the material transforms to modification I which undergoes dramatic evolution of its lattice parameters with increasing temperature. Synchrotron powder diffraction measurements confirm the existence of two polymorphic forms. Both modifications have been structurally characterized by single-crystal X-ray diffraction. The acid molecules in both crystal structures are organized into R22(8) dimer units at the first graph set level in modification I and at the second level in modification II.