Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Supramolecular ferric porphyrins as cyanide receptors in aqueous solution.

ABSTRACT: All fundamental data about binding of the cyanide to a supramolecular complex composed of a per-O-methylated ?-cyclodextrin dimer having an imidazole linker (Im3CD) and an anionic ferric porphyrin (Fe((III))TPPS) indicate that the Fe((III))TPPS/Im3CD complex is much better as an cyanide receptor in vivo than hydroxocobalamin, whose cyanide binding ability is lowered by its strong binding to serum proteins in the blood.

SUBMITTER: Watanabe K

PROVIDER: S-EPMC4018087 | biostudies-other | 2011 Dec

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Publications

Supramolecular ferric porphyrins as cyanide receptors in aqueous solution.

Watanabe Kenji K Kitagishi Hiroaki H Kano Koji K

ACS medicinal chemistry letters 20111020 12

All fundamental data about binding of the cyanide to a supramolecular complex composed of a per-O-methylated β-cyclodextrin dimer having an imidazole linker (Im3CD) and an anionic ferric porphyrin (Fe((III))TPPS) indicate that the Fe((III))TPPS/Im3CD complex is much better as an cyanide receptor in vivo than hydroxocobalamin, whose cyanide binding ability is lowered by its strong binding to serum proteins in the blood. ...[more]

PMID: 24900285

Similar Datasets

Ferric Chloride Complexes in Aqueous Solution: An EXAFS Study.

Project description:A series of concentrated aqueous solutions of ferric chloride with different chloride:iron(III) ratios has been studied by means of EXAFS to determine the structure around the iron(III) ion of the dominating species in such solutions. The dominating species in dilute acidic aqueous solution of ferric chloride, at less than 1 mmol·dm-3, are the hydrated iron(III) and chloride ions, while in concentrated aqueous solution and in solutions with an excess of chloride ions, up to 1.0 mol·dm-3, it is the trans-[FeCl2(H2O)4]+ complex. Possible higher chloroferrate(III) or dimeric [Fe2Cl6] complexes at room temperature, as proposed in the literature, were not observed in any of the studied solutions in spite of an excess of chloride ions of 1 mol·dm-3.

| S-EPMC5973949 | biostudies-literature

Equilibrium and kinetic studies of the aggregation of porphyrins in aqueous solution.

Project description:An investigation of the behavior of protoporphyrin IX, deuteroporphyrin IX, haematoporphyrin IX and coproporphyrin III in aqueous solution revealed extensive and complex aggregation processes. Protoporphyrin appears to be highly aggregated under all conditions studied. At concentrations below 4 muM, aggregation of deutero-, haemato- and coproporphyrin is probably restricted to dimerization. At approx. 4muM each of these three porphyrins exhibits sharp changes in spectra consistent with a "micellization" process to form large aggregates of unknown size. This critical concentration increases with increasing temperature and pH, but is not very sensitive to variation in ionic strength. Temperature-jump kinetic studies on deuteroporphyrin also imply an initial dimerization process, the rate constants for which are comparable with those for various synthetic porphyrins, followed by a further extensive aggragation. The ability of a particular porphyrin to dimerize appears to parallel that of the corresponding iron(III) complexes (ferrihaems), although it is thought that ferrihaems do not exhibit further aggregation under these conditions.

| S-EPMC1172573 | biostudies-other

Enhanced removal of As (V) from aqueous solution using modified hydrous ferric oxide nanoparticles.

Project description:Hydrous ferric oxide (HFO) is most effective with high treatment capacity on arsenate [As(V)] sorption although its transformation and aggregation nature need further improvement. Here, HFO nanoparticles with carboxymethyl cellulose (CMC) or starch as modifier was synthesized for the purpose of stability improvement and As(V) removal from water. Comparatively, CMC might be the optimum stabilizer for HFO nanoparticles because of more effective physical and chemical stability. The large-pore structure, high surface specific area, and the non-aggregated nature of CMC-HFO lead to increased adsorption sites, and thus high adsorption capacities of As(V) without pre-treatment (355 mg·g-1), which is much greater than those reported in previous studies. Second-order equation and dual-mode isotherm model could be successfully used to interpret the sorption kinetics and isotherms of As(V), respectively. FTIR, XPS and XRD analyses suggested that precipitation and surface complexation were primary mechanisms for As(V) removal by CMC modified HFO nanoparticles. A surface complexation model (SCM) was used to simulate As adsorption over pH 2.5-10.4. The predominant adsorbed arsenate species were modeled as bidentate binuclear surface complexes at low pH and as monodentate complexes at high pH. The immobilized arsenic remained stable when aging for 270 d at room temperature.

| S-EPMC5241682 | biostudies-literature

An isolated water droplet in the aqueous solution of a supramolecular tetrahedral cage.

Project description:Water under nanoconfinement at ambient conditions has exhibited low-dimensional ice formation and liquid-solid phase transitions, but with structural and dynamical signatures that map onto known regions of water's phase diagram. Using terahertz (THz) absorption spectroscopy and ab initio molecular dynamics, we have investigated the ambient water confined in a supramolecular tetrahedral assembly, and determined that a dynamically distinct network of 9 ± 1 water molecules is present within the nanocavity of the host. The low-frequency absorption spectrum and theoretical analysis of the water in the Ga4L6 12- host demonstrate that the structure and dynamics of the encapsulated droplet is distinct from any known phase of water. A further inference is that the release of the highly unusual encapsulated water droplet creates a strong thermodynamic driver for the high-affinity binding of guests in aqueous solution for the Ga4L6 12- supramolecular construct.

| S-EPMC7777103 | biostudies-literature

Investigations of ferric heme cyanide photodissociation in myoglobin and horseradish peroxidase.

Project description:The photodissociation of cyanide from ferric myoglobin (MbCN) and horseradish peroxidase (HRPCN) has definitively been observed. This has implications for the interpretation of ultrafast IR (Helbing et al. Biophys. J. 2004, 87, 1881-1891) and optical (Gruia et al. Biophys. J. 2008, 94, 2252-2268) studies that had previously suggested the Fe-CN bond was photostable in MbCN. The photolysis of ferric MbCN takes place with a quantum yield of ~75%, and the resonance Raman spectrum of the photoproduct observed in steady-state experiments as a function of laser power and sample spinning rate is identical to that of ferric Mb (metMb). The data are quantitatively analyzed using a simple model where cyanide is photodissociated and, although geminate rebinding with a rate of kBA ? (3.6 ps)(-1) is the dominant process, some CN(-) exits from the distal heme pocket and is replaced by water. Using independently determined values for the CN(-) association rate, we find that the CN(-) escape rate from the ferric myoglobin pocket to the solution at 293 K is kout ? (1-2) × 10(7) s(-1). This value is very similar to, but slightly larger than, the histidine gated escape rate of CO from Mb (1.1 × 10(7) s(-1)) under the same conditions. The analysis leads to an escape probability kout/(kout + kBA) ~ 10(-4), which is unobservable in most time domain kinetic measurements. However, the photolysis is surprisingly easy to detect in Mb using cw resonance Raman measurements. This is due to the anomalously slow CN(-) bimolecular association rate (170 M(-1) s(-1)), which arises from the need for water to exchange at the ferric heme binding site of Mb. In contrast, ferric HRP does not have a heme bound water molecule and its CN(-) bimolecular association rate is larger by ~10(3), making the CN(-) photolysis more difficult to observe.

| S-EPMC3631277 | biostudies-literature

Molecular recognition and scavenging of arsenate from aqueous solution using dimetallic receptors.

Project description:A series of copper(II), nickel(II) and zinc(II) dimetallic complexes were prepared and their affinities towards arsenate investigated. Indicator displacement assays (IDAs) were carried out to establish the complexes with best affinities towards arsenate. A di-zinc complex (3) was selected and its arsenate-binding abilities investigated by isothermal titration calorimetry (ITC). The X-ray crystal structure of this metallo-receptor bound to arsenate is also reported, which allowed us to establish the binding mode between 3 and this oxyanion. Immobilising 3 onto HypoGel resin yielded a novel adsorbent (Zn-HypoGel) with high affinity for arsenate. Adsorption of arsenate from competitive solutions and natural groundwater was greater than that of the commercially used iron oxide Bayoxide E33. Zn-HypoGel could be efficiently and simply regenerated by washing with sodium acetate solution.

| S-EPMC4517099 | biostudies-literature

Elucidating Atropisomerism in Nonplanar Porphyrins with Tunable Supramolecular Complexes.

Project description:Atropisomerism is a fundamental feature of substituted biaryls resulting from rotation around the biaryl axis. Different stereoisomers are formed due to restricted rotation about the single bond, a situation often found in substituted porphyrins. Previously NMR determination of porphyrin atropisomers proved difficult, if not almost impossible to accomplish, due to low resolution or unresolvable resonance signals that predominantly overlapped. Here, we shed some light on this fundamental issue found in porphyrinoid stereochemistry. Using benzenesulfonic acid (BSA) for host-guest interactions and performing 1D, 2D NMR spectroscopic analyses, we were able to characterize all four rotamers of the nonplanar 5,10,15,20-tetrakis(2-aminophenyl)-2,3,7,8,12,13,17,18-octaethylporphyirin as restricted H-bonding complexes. Additionally, X-ray structural analysis was used to investigate aspects of the weak host-guest interactions. A detailed assignment of the chemical signals suggests charge-assisted complexation as a key to unravel the atropisomeric enigma. From a method development perspective, symmetry operations unique to porphyrin atropisomers offer an essential handle to accurately identify the rotamers using NMR techniques only.

| S-EPMC7839692 | biostudies-literature

Supramolecular Dye Aggregate Assembly Enables Ratiometric Detection and Discrimination of Lysine and Arginine in Aqueous Solution.

Project description:Constructing sensor systems for rapid and selective detection of small biomolecules such as amino acids is a major area of focus in bioanalytical chemistry. Considering the biological relevance of arginine and lysine, significant efforts have been directed to develop fluorescent sensors for their detection. However, these developed sensors suffer from certain disadvantages such as poor aqueous solubility, technically demanding and time-consuming synthetic protocols, and more importantly, most of them operate through single wavelength measurements, making their performance prone to small variations in experimental conditions. Herein, we report a ratiometric sensor that operates through lysine- and arginine-induced dissociation of a supramolecular assembly consisting of emissive H-aggregates of a molecular rotor dye, thioflavin-T (ThT), on the surface of a polyanionic supramolecular host, sulfated β-cyclodextrin. This disassembly brings out the modulation of monomer-aggregate equilibrium in the system which acts as an ideal scheme for the ratiometric detection of lysine and arginine in the aqueous solution. Besides facile framework of our sensor system, it employs a commercially available inexpensive probe molecule, ThT, which provides an added advantage over other sensor systems that employ synthetically demanding probe molecules. Importantly, the distinctive feature of the ratiometric detection of arginine and lysine provides an inherent advantage of increased accuracy in quantitative analysis. Interestingly, we have also demonstrated that arginine displays a multiwavelength distinctive recognition pattern which distinguishes it from lysine, using a single supramolecular ensemble. Furthermore, our sensor system also shows response in heterogeneous, biologically complex media of serum samples, thus extending its possible use in real-life applications.

| S-EPMC6045403 | biostudies-literature

A Highly Efficient Phosphorescence/Fluorescence Supramolecular Switch Based on a Bromoisoquinoline Cascaded Assembly in Aqueous Solution.

Project description:Despite ongoing research into photocontrolled supramolecular switches, reversible photoswitching between room-temperature phosphorescence (RTP) and delayed fluorescence is rare in the aqueous phase. Herein, an efficient RTP-fluorescence switch based on a cascaded supramolecular assembly is reported, which is constructed using a 6-bromoisoquinoline derivative (G3 ), cucurbit[7]uril (CB[7]), sulfonatocalix[4]arene (SC4A4), and a photochromic spiropyran (SP) derivative. Benefiting from the confinement effect of CB[7], initial complexation with CB[7] arouses an emerging RTP signal at 540 nm for G3 . This structure subsequently coassembles with amphiphilic SC4A4 to form tight spherical nanoparticles, thereby further facilitating RTP emission (≈12 times) in addition to a prolonged lifetime (i.e., 1.80 ms c.f., 50.1 µs). Interestingly, following cascaded assembly with a photocontrolled energy acceptor (i.e., SP), the efficient light-driven RTP energy transfer occurs when SP is transformed to its fluorescent merocyanine (MC) state. Ultimately, this endows the final system with an excellent RTP-fluorescence photoswitching property accompanied by multicolor tunable long-lived emission. Moreover, this switching process can be reversibly modulated over multiple cycles under alternating UV and visible photoirradiation. Finally, the prepared switch is successfully applied to photocontrolled multicolor cell labeling to offer a new approach for the design and fabrication of novel advanced light-responsive RTP materials in aqueous environments.

| S-EPMC9108601 | biostudies-literature

New supramolecular trigonal prisms from zinc(II)- 1,4,7,10-tetraazacyclododecane (cyclen) complexes and trithiocyanurate in aqueous solution.

Project description:The multiple bonding between multinuclear zinc(II)-1,4,7,10-tetraazacyclododecane (cyclen, a 12-membered tetraamine) complexes and multidentate ligands is an effective method for constructing supramolecular complexes having well defined and distinct structures in aqueous solution. Herein we present examples of supramolecular D(3h) prisms formed by self-assembly of linearly dimeric or trimeric zinc(II)-cyclen complexes with a potentially trianionic C(3) subunit trithiocyanuric acid (TCA(3-)), wherein Zn(2+)-S(-) or Zn(2+)-N(-) coordination bonds and hydrogen bonds are responsible for stability of the multicomponent architectures in aqueous solution at neutral pH.

| S-EPMC122690 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data