Synthesis, structure and photoluminescence properties of heterometallic-based coordination polymers of trimesic acid.

Reacting trimesic acid (H3TMA, C9H6O6) with CaCl2 and MCl2 at 110 °C under hydrothermal conditions gave the isostructural heterobimetallic coordination polymers (CPs) catena-poly[[tetraaquazinc(II)]-µ-5-carboxybenzene-1,3-dicarboxylato-[tetraaquacalcium(II)]-µ-5-carboxybenzene-1,3-dicarboxylato], [CaZn(HTMA)2(H2O)8]n, 1, and catena-poly[[tetraaquacobalt(II)]-µ-5-carboxybenzene-1,3-dicarboxylato-[tetraaquacalcium(II)]-µ-5-carboxybenzene-1,3-dicarboxylato], [CaCo(HTMA)2(H2O)8]n, 2. Compounds 1 and 2 crystallize in the monoclinic space group C2/c. The solid-state structures consist of eight-coordinate CaII ions and six-coordinate MII ions. These ions are connected by a doubly deprotonated HTMA2- ligand to create a one-dimensional (1D) zigzag chain. Poly[[decaaquabis(µ3-benzene-1,3,5-tricarboxylato)calcium(II)dizinc(II)] dihydrate], {[CaZn2(TMA)2(H2O)10]·2H2O}n, 3, was found incidentally as a minor by-product during the synthesis of 1 at a temperature of 140 °C. It forms crystals in the orthorhombic space group Ccce. The structure of 3 consists of a two-dimensional (2D) layer composed of [Zn(TMA)] chains that are interconnected by CaII ions. The presence of aromatic carboxylic acid ligands and water molecules, which can form numerous hydrogen bonds and π-π interactions, increases the stability of the three-dimensional (3D) supramolecular architecture of these CPs. Compounds 1 and 2 exhibit thermal stability up to 420 °C, as indicated by the thermogravimetric analysis (TGA) curves. The powder X-ray diffraction (PXRD) data reveal the formation of unidentified phases in methanol and dimethyl sulfoxide, while 1 exhibits chemical stability in a wide range of solvents. The luminescence properties of 1 dispersed in various low molecular weight organic solvents was also examined. The results demonstrate excellent selectivity, sensitivity and recyclability for detecting acetone molecules in aqueous media. Additionally, a possible sensing mechanism is also outlined.

One-pot synthesis of iron oxide - Gamma irradiated chitosan modified SBA-15 mesoporous silica for effective methylene blue dye removal.

The development of adsorption technology and the processing of radiation have both been influenced by chitosan adsorbent (γ-chitosan), a raw material with unique features. The goal of the current work was to improve the synthesis of Fe-SBA-15 utilizing chitosan that has undergone gamma radiation (Fe-γ-CS-SBA-15) in order to investigate the removal of methylene blue dye in a single hydrothermal procedure. High-resolution transmission electron microscopy (HRTEM), High angle annular dark field scanning transmission electron microscopy (HAADF-STEM), small- and wide-angle X-ray powder diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR) and Energydispersive X-ray spectroscopy (EDS) were used to characterize γ-CS-SBA-15 that had been exposed to Fe. By using N2-physisorption (BET, BJH), the structure of Fe-γ-CS-SBA-15 was investigated. The study parameters also included the effect of solution pH, adsorbent dose and contact time on the methylene blue adsorption. The elimination efficiency of the methylene blue dye was compiled using a UV-VIS spectrophotometer. The results of the characterization show that the Fe-γ-CS-SBA-15 has a substantial pore volume of 504 m2 g-1 and a surface area of 0.88 cm3 g-1. Furthermore, the maximum adsorption capacity (Qmax) of the methylene blue is 176.70 mg/g. The γ-CS can make SBA-15 operate better. It proves that the distribution of Fe and chitosan (the C and N components) in SBA-15 channels is uniform.

Crystal structure of a new europium(III) compound based on thio-phene-acrylic acid.

A europium(III) coordination compound based on thio-phene-acrylic acid (Htpa), tri-aqua-tris-[3-(thio-phen-2-yl)prop-2-enoato-κ2 O,O']europium(III)-3-(thio-phen-2-yl)prop-2-enoic acid (1/3), [Eu(C7H5O2S)3(H2O)3]·3C7H6O2S or [Eu(tpa)3(H2O)3]·3(Htpa) (1), where tpa is the conjugate base of Htpa, has been synthesized and structurally characterized. Compound 1 crystallizes in the trigonal space group R3. The structure of 1 consists of a discrete mol-ecular complex [Eu(tpa)3(H2O)3] species and the Htpa mol-ecule. In the crystal, the two components are involved in O-H⋯O [ring motif R 2 2(8)] and C-H⋯π hydrogen-bonding inter-actions. These inter-actions were further investigated by Hirshfeld surface analysis, which showed high contributions of H⋯H, H⋯C/C⋯H and H⋯O/O⋯H contacts to the total Hirshfeld surfaces.

Crystal structure of catena-poly[[[bis-(1-benzyl-imidazole-κN)copper(II)]-µ-sulfato-κ2 O:O'-[tetra-kis-(1-benzyl-imidazole-κN)copper(II)]-µ-sulfato-κ2 O:O'] N,N-di-methyl-formamide disolvate dihydrate].

The title one-dimensional copper(II) coordination polymer, {[Cu(SO4)(C10H10N2)3]·C3H7NO·H2O} n or {[Cu(bzi)3(µ-O2SO2)]·H2O·DMF} n (bzi = 1-benz-yl-imidazole, C10H10N2; DMF = N,N-di-methyl-formamide, C3H7NO), is constructed by monodentate bzi ligands and bridging sulfate anions, leading to chains propagating parallel to the c axis. Within a chain, there are two crystallographic independent CuII ions, each with site symmetry , which form [CuN2O2] and [CuN4O2] polyhedra alternating along the chain direction. The crystal structure is consolidated by weak hydrogen-bonding, C-H⋯π and π-π inter-actions, leading to the formation of a three-dimensional supra-molecular network.

Novel gamma-irradiated chitosan-doped reduced graphene-CuInS2 composites as counter electrodes for dye-sensitized solar cells.

To address the issues associated with traditional counter electrodes, a novel gamma-irradiated chitosan-doped reduced graphene-CuInS2 composite (Chi@RGO-CIS) was used as the counter electrode (CE). The system was fabricated following a simple hydrothermal method. The prepared Chi@RGO-CIS was characterized by various spectroscopic and microscopic techniques. The synergistic effect between chitosan, CuInS2, and reduced graphene oxide can help in producing a large surface area. It can also help in the generation of catalytic sites toward I-/I3-redox electrolytes. We used a composite (based on electrical considerations) to study the effect of the amount of graphene on the characteristics and photovoltaic efficiency of the Chi@RGO-CIS composites. The solar cell assembled with 1.5% Chi@RGO-CIS exhibited an efficiency of 12.21%. The efficiency was higher than that of a Pt-based device (9.96%) fabricated under the same conditions. Hence, Chi@RGO-CIS can be potentially used as the CE of dye-sensitized solar cells (DSSCs). It can be used as a substitute for Pt in DSSCs.

Crystal structure and Hirshfeld surface analysis of tris-(acetohydrazide-κ2 N,O)(nitrato-κO)(nitrato-κ2 O,O')terbium(III) nitrate.

In the title lanthanide(III) compound, [Tb(NO3)2(C2H6N2O)3]NO3, the asym-metric unit contains one Tb3+ ion, three acetohydrazide (C2H6N2O) ligands, two coordinated nitrate anions, and an isolated nitrate anion. The Tb3+ ion is in a ninefold coordinated distorted tricapped trigonal-prismatic geometry formed by three oxygen atoms and three nitro-gen atoms from three different acetohydrazide ligands and three oxygen atoms from two nitrate anions. In the crystal, the complex mol-ecules and the non-coordinated nitrate anions are assembled into a three-dimensional supra-molecular architecture through extensive N-H⋯O hydrogen-bonding inter-actions between the amine NH groups of the acetohydrazide ligands and the nitrate oxygen atoms. Hirshfeld surface analysis was performed to aid in the visualization of inter-mol-ecular contacts.

Targeted Gold Nanohybrids Functionalized with Folate-Hydrophobic-Quaternized Pullulan Delivering Camptothecin for Enhancing Hydrophobic Anticancer Drug Efficacy.

This study presented a green, facile and efficient approach for a new combination of targeted gold nanohybrids functionalized with folate-hydrophobic-quaternized pullulan delivering hydrophobic camptothecin (CPT-GNHs@FHQ-PUL) to enhance the efficacy, selectivity, and safety of these systems. New formulations of spherical CPT-GNHs@FHQ-PUL obtained by bio-inspired strategy were fully characterized by TEM, EDS, DLS, zeta-potential, UV-vis, XRD, and ATR-FTIR analyses, showing a homogeneous particles size with an average size of approximately 10.97 ± 2.29 nm. CPT was successfully loaded on multifunctional GNHs@FHQ-PUL via intermolecular interactions. Moreover, pH-responsive CPT release from newly formulated-CPT-GNHs@FHQ-PUL exhibited a faster release rate under acidic conditions. The intelligent CPT-GNHs@FHQ-PUL (IC50 = 6.2 µM) displayed a 2.82-time higher cytotoxicity against human lung cancer cells (Chago-k1) than CPT alone (IC50 = 2.2 µM), while simultaneously exhibiting less toxicity toward normal human lung cells (Wi-38). These systems also showed specific uptake by folate receptor-mediated endocytosis, exhibited excellent anticancer activity, induced the death of cells by increasing apoptosis pathway (13.97%), and arrested the cell cycle at the G0-G1 phase. The results of this study showed that the delivery of CPT by smart GNHs@FHQ-PUL systems proved to be a promising strategy for increasing its chemotherapeutic effects.

Starch-Based Super Water Absorbent: A Promising and Sustainable Way to Increase Survival Rate of Trees Planted in Arid Areas.

This research aimed to scale up the production of starch-based super water absorbent (SWA) and to validate the practical benefits of SWA for agricultural applications. SWA was successfully prepared in an up-scaling production by radiation-induced graft polymerization of acrylic acid onto cassava starch. Chemical characterization by FTIR and thermal characterization by TGA showed results that differentiated starting materials from the prepared SWA, thus confirming effective preparation of starch-based SWA via radiation-induced graft polymerization. SEM results visibly revealed a highly porous morphology of the synthesized SWA, substantiating its high swelling ability. Results from the field tests, performed for two seasons, revealed that the prepared SWA was able to increase the survival rate of young rubber trees planted in arid area by up to 40%, while simultaneously enhancing the growth characteristics of the young rubber trees.

New organic/inorganic nanohybrids of targeted pullulan derivative/gold nanoparticles for effective drug delivery systems.

This study aimed to develop new organic/inorganic nanohybrids of targeted pullulan derivative/gold nanoparticles (FA-PABA-Q188-PUL@AuNPs) to improve the selectivity and efficacy of drugs. The chemical structure of targeted pullulan derivative, folic acid-decorated para-aminobenzoic acid-quat188-pullulan (FA-PABA-Q188-PUL), was designed for reducing, stabilizing, capping, and functionalizing AuNPs. Here, the key factors, including pH, temperature, and FA-PABA-Q188-PUL concentrations, were systematically optimized to control the morphology, size, and functionalization of multifunctional FA-PABA-Q188-PUL@AuNPs. Spherical FA-PABA-Q188-PUL@AuNPs obtained by a green, simple, and bio-inspired strategy under the optimum conditions were thoroughly characterized and had an average size of 12.6 ± 1.5 nm. The anticancer drug DOX was successfully loaded on monodispersed FA-PABA-Q188-PUL@AuNPs and the system exhibited excellent intracellular uptake, specificity, and physicochemical properties. The pH-responsive DOX release from FA-PABA-Q188-PUL@AuNPs-DOX showed fast release (85% after 72 h) under acidic conditions. Furthermore, FA-PABA-Q188-PUL@AuNPs-DOX enhanced the anticancer activity of DOX toward Chago-k1 cancer cells up to 4.8-fold and showed less cytotoxicity toward normal cells than free DOX. The FA-PABA-Q188-PUL@AuNPs-DOX induced the death of cells by increasing late apoptotic cells (26.4%) and arresting the cell cycle at S-G2/M phases. These results showed that innovative FA-PABA-Q188-PUL@AuNPs should be considered as new candidate platforms for anticancer drug delivery systems.

Facile and green synthesis of pullulan derivative-stabilized Au nanoparticles as drug carriers for enhancing anticancer activity.

In this work, we report for the first time AuNPs reduced/stabilized/capped with modified para-aminobenzoic acid-quat188-pullulan (PABA-QP) as excellent nanocarriers for delivery of doxorubicin to enhance the activity and safety of these systems. Spherical AuNPs@PABA-QP obtained by facile and green synthesis under optimum conditions were characterized by UV-VIS, TEM, EDS, SAED, XRD, ATR-FTIR and zeta-potential analyses and showed a narrow size distribution of 13.7 ±â€¯1.9 nm. DOX was successfully loaded onto AuNPs@PABA-QP via intermolecular interactions with high drug loading. DOX-AuNPs@PABA-QP (IC50 = 0.39µM) showed a 2.1-fold higher cytotoxicity against Chago cells than DOX alone (IC50 = 0.82µM), while exhibiting less cytotoxicity against normal cells (Wi-38). Moreover, DOX-AuNPs@PABA-QP also demonstrated high intracellular uptake by endocytosis, arrested in S and G2-M phases of the cell cycle (total S/G2-M increased to approximately 18.0%), induced excellent cytotoxicity, and increased the fraction of late-apoptotic cells (18.6%). Consequently, it is suggested that the novel combination of DOX-AuNPs@PABA-QP has the potential to be developed for human cancer treatment.

Highly efficient and facile fabrication of monodispersed Au nanoparticles using pullulan and their application as anticancer drug carriers.

This work presented a simple, rapid, green and efficient approach to the synthesis of gold nanoparticles using pullulan as a reducing/stabilizing/capping agent for drug delivery systems to increase the safety and efficacy of these systems. Monodispersed AuNPs@pullulan with prolonged stability were fully characterized by UV-VIS, FTIR, TEM, EDX, TGA and zeta potential analyses. A mechanism of AuNPs formation was proposed in which pullulan created reducing species for the reduction of Au3+ to AuNPs (Au0) that resulted in the formation of spherical AuNPs@pullulan with an average size of approximately 11±5nm, while the hydroxyl groups of pullulan were oxidized to carboxylate compounds. Novel cassiarin A chloride derivatives (3d and 3i) as candidate anticancer drugs were successfully loaded onto AuNPs@pullulan through electrostatic interactions. AuNPs@pullulan-3d (IC50=6.0±0.1µM) and AuNPs@pullulan-3i (5.2±0.1µM) exhibited a 10.2-fold and 7.1-fold higher cytotoxicity against KATO-III cells than free compounds 3d (60.9±0.6µM), 3i (37.1±0.2µM) and cisplatin (64.5±0.9µM), respectively. AuNPs@pullulan exhibited high cellular uptake, biocompatibility and non-cytotoxicity to normal cells. Therefore, AuNPs@pullulan-3d or AuNPs@pullulan-3i have the potential to be developed for treatment of gastric cancer.