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Jinguang Wu

Publications and source records attributed to Jinguang Wu.

At least 19 recordsLinked to original sources
PubMed2005

Crystal structures and spectroscopic characterization of galactitol complexes of trivalent lanthanide and divalent alkaline earth chlorides.

Crystal structures and FT-IR spectra of metal ion-galactitol (C6H14O6, the ligand here abbreviated as L) complexes: 2LaCl3*C6H14O6*10H2O and SrCl2*C6H14O6 complexes are reported. Crystal data of lanthanide chlorides (La3+, Nd3+, Sm3+, Eu3+, Tb3+)-galactitol complexes and alkaline earth chlorides (Ca2+, Sr2+)-galactitol complexes published earlier are summarized. Unlike other lanthanide ion-galactitol complexes (2MCl3*C6H14O6*14H2O), lanthanum ions give rise to two different structures: LaCl3*C6H14O6*6H2O (LaL1) and 2LaCl3*C6H14O6*10H2O (LaL2). Sr2+-galactitol complexes also crystallized with two structures: SrCl2*C6H14O6*4H2O (SrL1) and SrCl2*C6H14O6 (SrL2). These metal ions thus give different coordination structures with galactitol. The crystal structures and FT-IR spectra of lanthanide ion and alkaline earth ion-galactitol complexes were integrated to interpret the coordination modes of different metal ions. Similar IR spectra demonstrate the same coordination modes of the complexes.

Crystallization↗
PubMed2005

Interactions between metal ions and carbohydrates. The coordination behavior of neutral erythritol to lanthanum and erbium ions.

Lanthanide ions and erythritol form metal-alditol complexes with various structures. Lanthanum nitrate and erbium chloride coordinate to erythritol to give new coordination structures. The lanthanum nitrate-erythritol complex (LaEN), 2La(NO3)3.C4H10O(4).8H2O, La3+ exhibits the coordination number of 11 (namely 11 polar atoms bound to one lanthanum) and is 11-coordinated to two hydroxyl groups from one erythritol molecule, six oxygen atoms from three nitrate ions and three water molecules. One erythritol molecule is coordinated to two La3+ ions and links the two metal ions together. The ratio of M:L is 2:1. The erbium chloride-erythritol complex (ErE), ErCl2.C4H9O(4).2C2H5OH was obtained from ErCl3 and erythritol in aqueous ethanol solution and the structure shows that deprotonation reaction occurs in the reaction process. The Er3+ cation is 8-coordinated with three hydroxyl groups of one erythritol molecule, two hydroxyl groups from another erythritol molecule, two ethanol molecules, and one chloride ion. Erythritol provides its three hydroxyl groups to one erbium cation and two hydroxyl groups to another erbium cation, that is, one hydroxyl group is coordinated to two metal ions and therefore loses its hydrogen atom and becomes a oxygen bridge. Another chloride ion is hydrogen bonded in the structure. The results indicate the complexity of metal-sugar coordination.

Crystallization↗
PubMed2005

New, rapid fluorescence stain method for histologic sections using lanthanide complexes.

A new stain method for histologic sections different from traditional hematoxylin and eosin (H&E) methodology used two newly developed stain reagents from the lanthanide series, the antibiotic ofloxacin chelate of europium(III) and the ciprofloxacin hydrochloride chelate of terbium(III), exhibiting excellent fluorescence. These complexes are unique due to their nontoxicity, attractive fluorescent properties, rapid staining, and high water solubility. In this article, we focus on the interactions between biomolecules and synthesized lanthanide complexes and on the staining effect applied for tissue staining.

Ciprofloxacin↗
PubMed2005

FT-IR spectroscopic study on the variations of molecular structures of some carboxyl acids induced by free electron laser.

Free electron laser has been developed as tunable lasers over a wide range of wavelengths. Devices irradiating in the region of 6-16 microm (1666-625 cm-1) are operable in the Beijing free electron lasers facilities (BFEL). For understanding the interactions between FEL and biological tissues, in this study wavelength-selective infrared-induced structure changes of substances under irradiation by FEL were measured using FT-IR spectroscopy. The carboxyl acids and carboxylates samples investigated include salicylic acid, sulfosalicylic acid, cholic acid, deoxycholic acid, sodium cholate and sodium deoxycholate. The changes of the FT-IR spectra of the molecules prove that the spectral variations of the samples induced by FEL are closely related to their hydrogen bond networks.

Carboxylic Acids↗
PubMed2005

First hydrotalcite-like sulfonate coordination network incorporating robust cationic layers and flexible interlayer interactions.

In this paper, a novel coordination network of D,L-homocysteic acid with strontium chloride is reported. This compound exhibits an infinite microporous multilayered structure, describable as one-dimensional coordination-based microtubes cross-linking into cationic layers. Chloride anions are intercalated between layers to neutralize the charge, and the layers further pack into a three-dimensional solid via electrostatic interactions and hydrogen bonding. Thermogravimetric analysis (TGA), variable-temperature Fourier transform infrared spectroscopy (FT-IR), and powder X-ray diffraction (XRD) are presented to extensively study the structure. Results show that the compound is stable up to 326 degrees C. Below this temperature, the layered structure is sustained in the process of the reversible loss/gain of coordinated water, confirming that the network involves a robust coordination-based cationic layer framework but rather flexible interlayer interactions. This compound and its analogies are expected to have potential applications in anion exchange and gas storage.

Journal Article↗
PubMed2005

Effect of dl-homocysteic acid on W/O microemulsions of potassium naphthenate/1-octanol-n-heptane.

The effect of DL-homocysteic acid (DL-2-amino-4-sulfonobutyric acid) on W/O microemulsion of potassium naphthenate (80%) and naphthenic acid (20%) in mixed solvent (1-octanol and n-heptane) has been found in four phases: (1) Interaction between the amino acid molecules and the polar head groups of the surfactant through hydrogen bonding enhances solubilization in the aqueous cores. (2) The interaction results in the growth of the microemulsion droplets and the homogenization of the particle size distribution. (3) The microstructure of the solubilized water remains unchanged, except that the polarity of the interface is affected. (4) The transition point is reduced to lower water content. A possible mechanism is proposed.

Amino Acids↗
PubMed2005

Interactions between metal ions and carbohydrates. The coordination behavior of neutral erythritol to neodymium ion.

A single crystal of a coordinated complex of neutral erythritol (C4H10O4,E) with a neodymium ion, NdE(II), was synthesized and studied using FT-IR and X-ray diffraction analysis. In NdE(II) (NdCl3.2.5C4H10O4.C2H5OH) the Nd3+ coordinates with one chloride ion and eight OH groups from three erythritol molecules. There are two neodymium centers linked by one erythritol molecule with same coordination structure in the molecule. Two erythritol molecules provide 1,3,4-hydroxyl groups to coordinate with a neodymium ion; another erythritol molecule coordinates to two Nd ions via its 1,2-hydroxyl groups and 3,4-hydroxyl groups, respectively. The OH groups of erythritol act as ligand to coordinate to neodymium ions, and OH groups of erythritol form hydrogen bond networks that link chain and layer together to build three-dimensional structures. The ratio of metal to ligand is 1:2.5. The structure of NdE(II) is more complicated than the previously reported NdE(I), which is NdCl3.C4H10O4.6H2O; in NdE(I), Nd3+ is coordinated to four hydroxyl groups from two erythritol molecules, four water molecules and one chloride ion. The results indicate the complexity of metal-sugar interaction.

Journal Article↗
PubMed2004

Complexation of trivalent lanthanide cations by erythritol in the solid state. The crystal structure and FT-IR study of 2EuCl3.2C4H10O4.7H2O.

Erythritol was chosen to study the interactions between metal ions and carbohydrates. FTIR spectroscopy results indicate that a EuCl3-erythritol complex different from a previously reported one was obtained. The crystal structure of EuCl3-erythritol complex, 2EuCl3.2C4H10O4.7H2O, Mr=443.49, a=13.846(3) A , b=7.4983(15) A, c=14.140(3) A, beta=116.39(3) degrees, V=1315.1(5) A(3), Z=4, mu=5.394 mm(-1) and R=0.0395 for 2965 observed reflections and 143 parameters, was determined. Characteristic of this complex is the presence of binuclear europium ions with different coordination structures. One Eu3+ ion is nine-coordinated, with five Eu-O bonds from water molecules, and four from hydroxyl groups of two erythritol molecules and another Eu3+ is eight-coordinated with two water molecules, two chloride ions, and four hydroxyl groups from two erythritol molecules. Erythritol provides two hydroxyl groups to one lanthanide ion and the other two to another rare earth ion. The OH, CO stretching and other vibrations are shifted in the IR spectra of the complexes and the results are consistent with the crystal structure.

Cations↗
PubMed2004

Interactions between metal ions and carbohydrates: the coordination behavior of neutral erythritol to transition metal ions.

The single crystals of coordinated complexes of neutral erythritol (C4H10O4) with various transition metal ions were synthesized and studied using FT-IR and single crystal X-ray diffraction analysis. Two CuCl2-erythritol complexes (denoted as CuE(I) and CuE(II)) were obtained. In CuE(I), Cu2+ coordinates with two chloride ions and four OH groups from two erythritol molecules. Two copper centers are linked by one erythritol molecule to form a zigzag chain. For CuE(II), each Cu2+ coordinates with two OH groups from an erythritol molecule and two chloride ions. The crystal of CuE(II) contains complexed and free erythritol, the dimers of [Cu2Cl4(C4H10O4)] further form a [Cu2Cl4(C4H10O4)]infinity chain via secondary Cu...Cl bonds, both the dimer unit of [Cu2Cl4.(C4H10O4)] and non-coordinated C4H10O4 unit exist side by side in the crystal. MnCl2-erythritol complex whose structure is similar to CuE(I) is also acquired. The OH groups of erythritol act as ligand to coordinate to metal ions on one hand, one the other hand, OH groups form hydrogen bonds network that link chain and layer together to build three-dimensional structures.

Carbohydrates↗
PubMed2004

Interactions between metal ions and carbohydrates: the coordination behavior of neutral erythritol to zinc and europium nitrate.

The single crystals of coordinated complexes of neutral erythritol (C4H10O4) with zinc nitrate and europium nitrate were synthesized and studied using FT-IR and single crystal X-ray diffraction analysis. In the structure of Zn(NO3)2.C4H10O4, ZnEN (E denotes erythritol, N represents nitrate), Zn2+ is coordinated to four hydroxyl groups from two erythritol molecules and two oxygen atoms from two nitrates. Two Zn2+ are connected by one erythritol molecule to form Zn(C4H10O4)(NO3)2 chain, and layers formed by above chain pile to produce 3D structures. In the structure of Eu(NO3)3.C4H10O4.C2H5OH, EuEN, Eu3+ is 10-coordinated by six oxygen atoms from three nitrate ions, three hydroxyl groups from one erythritol molecule and one hydroxyl group from ethanol. In the above erythritol complexes, two hydroxyl groups of erythritol coordinate to one metal ion and the other two to another metal ion or erythritol acts as three-hydroxyl groups donor. The OH groups of erythritol act as ligand to coordinate to metal ions on one hand, one the other hand, OH groups form hydrogen bonds network to build three-dimensional structures.

Journal Article↗
PubMed2004

The interaction between amino acids and metal ions (I). The FT-IR spectroscopic study of the binding between D,L-homocysteic acid and alkali metal ions.

D,L-Homocysteic acid (DLH), an amino acid in the mammalian central nervous system, can excite the cerebral activities and has been proposed as an agonist of endogenous glutamate receptor. It contains -NH(3)(+), -COOH and -SO(3)(-) groups, therefore, the interactions between DLH and metal ions may be expected. In the present investigation, the complexes of DLH with NH4(+), Li+, Na+ and K+ at different pH conditions were synthesized and characterized by Fourier transform infrared (FT-IR) spectroscopy. It was concluded that the structures of the complexes prepared at pH 2.6 and 4.0 are similar to each other and the C=O groups are mono-dentate coordination for these complexes. However, the structures of the complexes synthesized at pH 13.0 change considerably from the complexes at pH 2.6 and 4.0, which show that dissociation has occurred in aqueous solution. The four cations coordinate to DLH, which result in the rearrangement of the hydrogen bond network and the skeletal structure change of the ligand.

Homocysteine↗
PubMed2003

Extraction of inorganic acids with neutral phosphorus extractants based on a reverse micelle/microemulsion mechanism.

The extraction of inorganic acids such as HCl, HNO(3), H(2)SO(4), and HClO(4) has been investigated in three neutral phosphorus compound systems, i.e., tri-n-butyl phosphate (TBP), di-isoamylmethyl phosphonate (DiAMP), and trialkylphosphine oxide (TRPO, C(6)-C(8)), using n-heptane as a diluent. The techniques of electrical conductivity, Fourier transform infrared (FTIR) spectroscopy, 1H NMR, and dynamic laser scattering (DLS) were selected to characterize the organic phases. The results indicate that the interaction between acids and neutral phosphorus compounds follows a molecule-ion combination mechanism. When the acid in the organic phase reaches a certain concentration, the molecular-ion species have a tendency to self-assemble and form reverse micelles/microemulsions (W/O). The further increase of the acid concentration leads the organic phase to split into two layers. Extractants and acids are mainly located in the down layer, in which aggregations are formed. The tendency to form microemulsions follows TRPO > DiAMP > TBP.

Journal Article↗
PubMed2003

Interactions between metal ions and carbohydrates. Coordination behavior of neutral erythritol to Ca(II) and lanthanide ions.

The study of the sugar-metal ion interactions remains one of the main objectives of carbohydrate coordination chemistry because the interactions between metal ions and carbohydrates are involved in many biochemical processes. This paper presents a comparison of coordination structures of erythritol with alkaline-earth-metal and lanthanide chloride and nitrate in the solid state using FT-IR and X-ray diffraction. Neutral, nondeprotonated erythritol (E) reacts with CaCl(2) to give three CaCl(2)(-)erythritol (CaE(I), CaE(II), CaE(III)) complexes, showing that three of the five general features of calcium-carbohydrate complexes deduced in the reference encounter contrary examples. Different coordination structures have been observed for calcium and lanthanide chloride and nitrates. The coordination of carbohydrates to metal ions is complicated, and erythritol, chloride ions, nitrates, water molecules, and ethanol (crystallization medium and reaction solvents) have the chance to coordinate to metal ions. IR spectral results show that different lanthanide ions, from LaCl(3) to TbCl(3), have similar coordination structures with erythritol. The results show that erythritol can act as two bidentate neutral ligands (CaE(I), CaE(II), CaE(III), CaEN, PrE, NdE) or as a three-hydroxyl donor (NdEN). The IR results are consistent with the crystal structures.

Calcium↗
PubMed2003

Sugar interaction with metal ion: crystal structure and spectroscopic study of SrCl2.galactitol.4H2O.

The crystal structure of SrCl(2).galactitol.4H(2)O has been determined. It belongs to monoclinic system, C2/c space group with unit cell dimensions: a=13.9849(3), b=14.1601(5), c=8.3026(3) A, beta=104.621(2) degrees, V=1590.9(9) A(3) and Z=4. Each Sr(2+) ion in the unit cell binds to two molecules of galactitol through O2 and O3 in one alditol and O2' and O3' in the other, as well as to four water molecules. Sr-O distances in SrCl(2).galactitol.4H(2)O complex range from 2.5420 to 2.6359 A. FT-IR, Raman and far-IR spectra of SrCl(2).galactitol.4H(2)O all show that SrCl(2) coordinates with galactitol through OH groups of the sugar molecule to form the new complex.

Carbohydrates↗
PubMed2003

The pressure tunning Raman spectral studies of the bilirubinIXalpha and neutral calcium bilirubinate at high external pressure.

The bilirubinIXalpha and its neutral calcium bilirubinate were studied using Raman spectroscopy at high external pressure. The results showed that the bilirubinIXalpha has two pressure-induced phase transitions (15-18 and 30-36 kbar) and three pressure phase areas. Its pressure sensitivities in the low-pressure phase are very low. It is believed that the four internally hydrogen bonds in bilirubinIXalpha molecule cause the atoms to attract each other tightly in the bilirubinIXalpha molecule. Therefore, the low pressure is not strong enough to shorten the bonds significantly. The pressure sensitivities in the middle-pressure phase are much higher than those in the low-pressure phase, but those in the high-pressure phase are slightly lower than in the middle-pressure phase. There is only one pressure-induced phase transition (25-34 kbar) in the neutral calcium bilirubinate. The pressure sensitivities in the low-pressure phase are higher than those in the high-pressure phase as usually.

Bilirubin↗
PubMed2002

A new mechanism of Raman enhancement and its application.

Strong electronic Raman bands corresponding to the transition between 4I9/2 and 4I11/2 manifolds of Nd3+, caused by a Raman-enhancement effect, are observed in the FT-Raman spectrum of Nd2O3. Neither resonance enhancement (RR) nor surface enhancement (SERS) accounts for the Raman enhancement observed here. We propose a new mechanism of Raman enhancement called the "feed-back" mechanism. A YAG laser excites the final state of the Raman transition (4I11/2 of Nd3+) to the 4F3/2 state and causes a significant decrease in the population of Nd3+ at the 4I11/2 state. This causes the population ratio of Nd3+ at 4I9/2 and 4I11/2 to deviate from the value required by Boltzmann's law. To restore equilibrium, Raman scattering is enhanced so that more Nd3+ ions are brought from the 4I9/2 state to the 4I11/2 state. This hypothesis gets support from the temperature-variable FT-Raman spectroscopic results. Additionally, obvious differences between the Stokes and anti-Stokes Raman spectrum of Nd3+ provide further evidence to support the feed-back mechanism. The Raman-enhancement effect confers on the electronic Raman bands a special ability to reflect the variation of coordinated structure around metal ions. The structural variations in polymer-metal ion composites and biomineralization systems have been investigated by using the electronic Raman bands.

Journal Article↗
PubMed2002

Sugar interaction with metal ions. The coordination behavior of neutral galactitol to Ca(II) and lanthanide ions.

The crystal structures of CaCl(2).galactitol.4 H(2)O and 2EuCl(3).galactitol.14 H(2)O were determined to compare the coordination behavior of Ca and lanthanide ions. The crystal system of the Ca-galactitol complex, CaCl(2).C(6)H(14)O(6).4 H(2)O, is monoclinic, Cc space group. Each Ca ion is coordinated to eight oxygen atoms, four from two galactitol molecules and four from water molecules. Galactitol provides O-2, -3 to coordinate to one Ca(2+), and O-4, -5 with another Ca(2+), to form a chain structure. The crystal system of the Eu-galactitol complex, 2EuCl(3).C(6)H(14)O(6).14 H(2)O, is triclinic, P1; space group. Each Eu ion is coordinated to nine oxygen atoms, three from an alditol molecule and six from water molecules. Each galactitol provides O-1, -2, -3 to coordinate with one Eu(3+) and O-4, -5, -6 with another Eu(3+). The other water molecules are hydrogen-bonded in the structure. The similar IR spectra of Pr-, Nd-, Sm-, Eu-, Dy-, and Er-galactitol complexes show that those lanthanide ions have the same coordination mode to neutral galactitol. The Raman spectra also confirm the formation of metal ion-carbohydrate complexes.

Calcium Chloride↗