Silica-gelatin hybrid aerogels of varying gelatin content (from 4 wt.% to 24 wt.%) can be conveniently impregnated with hydrophobic active agents (e.g. ibuprofen, ketoprofen) in supercritical CO2 and used as drug delivery systems. Contrast variation neutron scattering (SANS) experiments show the molecular level hybridization silica components aerogel carriers. The are amorphous, homogeneously dispersed these porous, matrices. Importantly, both fast retarded release achieved silica-gelatin...

Reactions of Al(III) and Ga(III) with citric acid in aqueous solutions, yielded the complexes (NH4)5{M(C6H4O7)2}·2H2O (M(III) = Al (1), Ga (2)) at alkaline pH, (Cat)4{M(C6H5O7)(C6H4O7)}·nH2O (3), (4), Cat. NH4+, n 3; M(III) (5), (6), K+, 4) acidic pH. All compounds were characterized by spectroscopic (FT-IR, 1H, 13C, 27Al NMR, 13C-MAS NMR) X-ray techniques. Complex 1 crystallizes space group P1̄, a 9.638(5) Å, b 9.715(5) c 7.237(4) α 90.96(1)°, β 105.72(1)°, γ 119.74(1)°, V 557.1(3) Å3, Z 1....

This study consists of two parts: The first part comprised an experimental determination the kinetic parameters for exchange water between UO2(H2O)5(2+) and bulk water, including ab initio at SCF MP2 levels geometry UO2(H2O)5(2+), UO2(H2O)4(2+), UO2(H2O)6(2+) thermodynamics their reactions with water. In second we made rate in uranyl complexes investigated how this might depend on inter- intramolecular hydrogen bond interactions. studies, by using 17O NMR, Tb3+ as a chemical shift reagent,...

Dual drug-loaded dendrimer/CD nanohybrids can be developed for fluorescence imaging and enhanced chemotherapy of cancer cells.

Generation 5 (G5) poly(amidoamine) dendrimers with acetyl (G5.NHAc), glycidol hydroxyl (G5.NGlyOH), and succinamic acid (G5.SAH) terminal groups were used to physically encapsulate an anticancer drug doxorubicin (DOX). Both UV-vis spectroscopy multiple NMR techniques including one-dimensional two-dimensional applied investigate the interactions between different DOX. The influence of surface functional G5 on DOX encapsulation, release kinetics, cancer cell inhibition effect was investigated....

In this study, we report the findings of a morphological analysis resorcinol-formaldehyde (RF)-based carbon aerogel (CA) and its graphene oxide (GO)-doped version (CA-GO), prepared for possible applications as an electrode material. Beyond some electron microscopic N2 sorption investigations, mostly used NMR cryoporometry relaxometry to characterize gels in wet state, they are usually applied. The precursor RF polymer was both with without GO subsequently carbonized into aerogel. Modifying...

A cyclen-based ligand containing trans-acetate and trans-methylenephosphonate pendant groups, H6DO2A2P, was synthesized its protonation constants (12.6, 11.43, 5.95, 6.15, 2.88, 2.77) were determined by pH-potentiometry 1H NMR spectroscopy. The first two protonations shown to occur at the macrocyclic ring N–CH2–PO32– nitrogens while third fourth phosphonate groups. In parallel with of −PO32– protons from NH+−CH2−PO32– are transferred N−CH2−COO– nitrogens. stability Ca2+, Cu2+, Zn2+ (ML, MHL,...

The conformational properties of lanthanide(III) complexes with the mono- and biphosphonate analogues 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (DOTA) are investigated by means density functional theory (DFT) calculations NMR spectroscopy. Geometry optimizations performed at B3LYP/6-31G(d) level using a 46 + 4f(n) effective core potential for lanthanides provide two energy minima corresponding to square-antiprismatic (SAP) twisted (TSAP) geometries. Our give relative free energies...

Abstract A detailed study of the structures, thermodynamic stabilities and kinetics dissociation Ga 3+ , In Cu 2+ complexes formed with heptadentate ligand AAZTA is reported. The stability constants (log K ML ) are 22.18, 29.58 22.27, respectively, which suggests that seven‐membered‐ring skeleton suited to accommodation these metal ions. solid‐state structure [Cu(H 2 AAZTA)] · H O shows a distorted octahedral coordination. equatorial coordination sites occupied by one ring N atoms, water...

We report the construction and characterization of 99mTc-labeled arginine-glycine-aspartic acid (RGD)-polyethylenimine (PEI) conjugates with entrapped gold nanoparticles in cavities (RGD-99mTc-Au PENPs) for dual-mode single-photon emission computed tomography (SPECT)/computed (CT) imaging an orthotopic hepatic carcinoma model. In this study, PEI was successively decorated diethylenetriaminepentaacetic acid, poly(ethylene glycol) (PEG), PEGylated RGD segments, utilized as effective...

Several Bi(III) complexes are used in medicine as drugs. Bi(DO3A-Bu) has recently been proposed a nonionic contrast agent X-ray imaging (H3DO3A-Bu = 10-[2,3-dihydroxy-(1-hydroxymethyl)propyl]-1,4,7,10-tetraazacyclododecane-1,4,7,-triacetic acid). The solution equilibria and NMR structure dynamics of the similar Bi(DOTA)- have investigated (H4DOTA 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic stability constants were determined with study competition between Br- ions ligands DOTA or...

A careful reinvestigation by high-field 19F NMR (470 MHz) spectroscopy has been made of the Al3+/F- system in aqueous solution under carefully controlled conditions pH, concentration, ionic strength (I), and temperature. The spectra show five distinct signals at 278 K I = 0.6 M (TMACl) which have attributed to complexes AlFi(3-i)+(aq) with i < or 5. There was no need invoke AlFi(OH)j(3-i-j)+ mixed model our experimental (pH 6.5), nor any evidence obtained for formation AlF6(3-)(aq) very high...

Generation 5 ethylenediamine (EDA)-cored poly(amidoamine) (PAMAM) dendrimers (E5, E denotes the EDA core and generation number) with different degrees of acetylation carboxylation were synthesized used as a model system to investigate effect charge influence dendrimer surface modifications on electrophoretic mobility (EM) molecular distribution. The surface-modified characterized by size-exclusion chromatography, 1H NMR, MALDI-TOF-MS, PAGE, CE. focus our study was determine how EM changes...

Chemodynamic therapy (CDT) has received increasing attention due to its unique tumor microenvironment (TME) responsiveness and minimal adverse side effects, but the therapeutic effect of CDT alone is always limited low Fenton or Fenton-like reaction efficiency at sites. Herein, Fe-doped layered double hydroxide (LDH) nanosheets were synthesized load anticancer drug epigallocatechin-3-O-gallate (EGCG) then conjugated with boronic acid-modified hyaluronic acid for targeted cooperative...

The effects of dealumination, pore size, and calcination on the efficiency (as expressed in relaxivity) Gd3+-loaded zeolites for potential application as magnetic resonance imaging (MRI) contrast agents were studied. Partial dealumination NaY or NaA by treatment with (NH4)2SiF6 diluted HCl resulted materials that, upon loading Gd3+, had a much higher relaxivity than corresponding non-dealuminated materials. Analysis 1H NMR dispersion profiles various showed that this can be mainly ascribed...

The activation parameters and the rate constants of water-exchange reactions MnIIITE-2-PyP5+ (meso-tetrakis(N-ethylpyridinium-2-yl)porphyrin) as cationic, MnIIITnHex-2-PyP5+ (meso-tetrakis(N-n-hexylpyridinium-2-yl)porphyrin) sterically shielded MnIIITSPP3− (meso-tetrakis(4-sulfonatophenyl)porphyrin) anionic manganese(III) porphyrins were determined from temperature dependence 17O NMR relaxation rates. at 298 K obtained 4.12 × 106 s−1, 5.73 2.74 107 respectively. On basis entropies...

Pore network and adsorption properties of mesoporous silica aerogel: a mechanistic study on the timescale seconds.

The internal spatial structures of PEGylated polyethylenimine-entrapped gold nanoparticles can be effectively analyzed <italic>via</italic> advanced NMR techniques.

Carbon aerogels prepared from resorcinol-formaldehyde are promising platforms for electrodes, catalysts, adsorbents in environmental chemistry and as electric conductors. For these applications the knowledge of their structure behavior aqueous medium is essential. In this work two (RF) carbon different ways were characterized with various NMR methods while pore was stepwise saturated water. The wetting properties studied by vapor adsorption low-field relaxometry, morphology followed...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTKinetic Behavior of Carbonate Ligands with Different Coordination Modes: Equilibrium Dynamics for Uranyl(2+) Carbonato Complexes in Aqueous Solution. A 13C and 17O NMR StudyIstvan Banyai, Julius Glaser, Karoly Micskei, Imre Toth, Laszlo ZekanyCite this: Inorg. Chem. 1995, 34, 14, 3785–3796Publication Date (Print):July 1, 1995Publication History Published online1 May 2002Published inissue 1 July...