Pingli Kang

Detection of reactive oxygen species (ROS) generated by TiO2(R), TiO2(R/A) and TiO2(A) under ultrasonic and solar light irradiation and application in degradation of organic dyes

In the present work, the rutile, anatase and mixed (rutile and anatase) crystal phase TiO(2) powders were irradiated by ultrasound and solar light, respectively, and the generation of reactive oxygen species (ROS) were detected through the oxidation reaction from 1,5-diphenyl carbazide (DPCI) to 1,5-diphenyl carbazone (DPCO). The DPCO can be extracted by the mixed solvent of benzene and carbon tetrachloride and the extract liquors display an obvious absorption peak around 563nm. In addition, the influences of (ultrasonic or solar light) irradiation time, TiO(2) addition amount and DPCI concentration on the quantities of generated ROS were also reviewed. The kinds of generated ROS were determined by using several radical scavengers. At last, the researches on the sonocatalytic and photocatalytic degradation of several organic dyes were also performed. It is wished that this paper might offer some important subjects for broadening the applications of sonocatalytic and photocatalytic technologies.

The investigation of sonocatalytic activity of Er3+:YAlO3/TiO2-ZnO composite in azo dyes degradation

In this work, the emphasis was mainly placed on investigating the sonocatalytic activity of TiO(2)-ZnO mixed with Er(3+):YAlO(3), namely, Er(3+):YAlO(3)/TiO(2)-ZnO composite. It is able to utilize the sonoluminescence light to improve the sonocatalytic degradation of organic dyes. The Er(3+):YAlO(3) as up-conversion luminescence agent was synthesized by sol-gel and auto-combustion method, and then Er(3+):YAlO(3)/TiO(2)-ZnO composite as sonocatalyst were prepared by ultrasonic dispersion and liquids boil method. The prepared up-conversion luminescence agent and composites were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). Acid Red B dye was selected to examine the sonocatalytic activity of Er(3+):YAlO(3)/TiO(2)-ZnO composite. The degradation reaction processes were monitored by UV-vis spectrophotometer and ion chromatogram. The influences on the activity of the Er(3+):YAlO(3)/TiO(2)-ZnO such as Ti/Zn molar ratio, heat-treated temperature and heat-treated time were studied. The results showed that the Er(3+):YAlO(3)/TiO(2)-ZnO composite exhibited a significantly high sonocatalytic activity compared with other catalysts in the degradation of Acid Red B. And the sonocatalyst with 1:1 Ti/Zn molar ratio heat-treated at 550°C for 60min showed the highest sonocatalytic activity. At last, the experiment also indicated that it has a good sonocatalytic activity to degrade other organic dyes.

Synthesis of Er3+:Y3Al5O12 and its effects on the solar light photocatalytic activity of TiO2–ZrO2 composite

The Er3+:Y3Al5O12 as an upconversion luminescence agent, which can transform visible light into ultraviolet light, was synthesized by nitrate–citrate acid and calcined method. Then, a novel photocatalyst, Er3+:Y3Al5O12/TiO2–ZrO2, was prepared using ultrasonic dispersion and liquid boiling method. The samples were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). In succession, the degradation process of organic dye was monitored by UV–Vis spectrum and ion chromatography for verifying the photocatalytic activity of Er3+:Y3Al5O12/TiO2–ZrO2. The influences on its photocatalytic activity such as Ti/Zr molar ratio, heat-treated temperature, and time were studied. In addition, the influences of initial concentration, Er3+:Y3Al5O12/TiO2–ZrO2 amount, solar light irradiation time, and organic dye category on the photocatalytic degradation efficiency were also investigated. It was found the photocatalytic activity of Er3+:Y3Al5O12/TiO2–ZrO2 was superior to Er3+:Y3Al5O12/TiO2 and Er3+:Y3Al5O12/ZrO2. Therefore, the Er3+:Y3Al5O12/TiO2–ZrO2 is a useful photocatalytic material for the wastewater treatment duo to efficient utilization of solar light.

Synthesis, characterization and antibacterial activity of indium(III) complexes with adamantane-ring containing Schiff bases

Indium(III) chloride tetrahydrate and Schiff-base ligands derived from adamantaneamine and 3-/4-methoxysalicylaldehyde gave two complexes, C22H32Cl3InN2O3 (1) and C36H44Cl3InN2O4 (2), respectively. The complexes were characterized by IR, 1H NMR, elemental analysis, molar conductance, thermal analysis, and single-crystal X-ray diffraction. Complex 1 crystallizes in the monoclinic system, P21/n space group with the asymmetric unit consisting of one indium(III), one N-(3-methoxysalicylidene)-aminoadamantane (L1), three chlorides and one N,N-dimethylformamide molecule. The indium is six-coordinate with reversed triangular-prism geometry via three oxygens and three chlorides. Complex 2 crystallizes in the triclinic system, P 1 space group; the asymmetric unit consists of one indium(III), two N-(4methoxysalicylidene)-aminoadamantane (L2), and three chlorides. The indium is five-coordinate with distorted trigonal-bipyramidal geometry via two oxygens and three chlorides. Antibacterial activities of the complexes have been investigated against Escherichia coli and Staphylococcus aureus.

Syntheses, structural determination, and binding studies of mononuclear nine-coordinate (enH2)[SmIII(egta)(H2O)]2 · 6H2O and 2-D ladder-like nine-coordinate (enH2)1.5[SmIII(ttha)] · 4.5H2O

Two lanthanide complexes, (enH2)[SmIII(egta)(H2O)]2 · 6H2O (1) (en = ethylenediamine and H4egta = ethyleneglycol-bis-(2-aminoethylether)-N,N,N′,N′-tetraacetic acid) and (enH2)1.5[SmIII(ttha)] · 4.5H2O (2) (H6ttha = triethylenetetramine-N,N,N′,N″,N′″,N′″-hexaacetic acid), have been synthesized and characterized by IR spectroscopy, thermal analysis, and single-crystal X-ray diffraction. The (enH2)[SmIII(egta)(H2O)]2 · 6H2O is mononuclear nine-coordinate and crystallizes in the monoclinic crystal space group P21/n with the cell dimensions a = 13.0563(13) Å, b = 12.6895(11) Å, c = 14.9497(15) Å, β = 105.782(2)°. The polymeric (enH2)1.5[SmIII(ttha)] · 4.5H2O is also nine-coordinate crystallizing in the monoclinic crystal space group P21/n, but with cell dimensions a = 17.7800(16) Å, b = 9.7035(10) Å, c = 22.096(2) Å, β = 118.8740(10)°. Each ethylenediammonium (en ) cation in (enH2)[SmIII(egta)(H2O)]2 · 6H2O connects three adjacent [SmIII(egta)(H2O)]− anions through hydrogen bonds, while in (enH2)1.5[SmIII(ttha)] · 4.5H2O, there are two types of en cations, which form hydrogen bonds with the neighboring [SmIII(ttha)]3− anions, leading to the formation of a 2-D ladder-like layer structure.

Spectroscopic studies on interaction and sonodynamic damage of metallochlorophyllin (Chl-M (M = Fe, Zn and Cu)) to protein under ultrasonic irradiation

In this paper, the chlorophyll derivatives, metallochlorophyllin (Chl-M) (M=Fe, Zn and Cu) including chlorophyllin iron (Chl-Fe), chlorophyllin zinc (Chl-Zn) and chlorophyllin copper (Chl-Cu), were adopted as sonosensitizers to combine with ultrasonic irradiation, and the sonodynamic damage of bovine serum albumin (BSA) was investigated. At first, the interaction of Chl-M with BSA was studied by fluorescence spectroscopy. The results show that the quenching mechanism belongs to a static process and among them the affinity of Chl-Fe to BSA is the most obvious. Then, some influence factors on the sonodynamic damage of BSA molecules in the presence of Chl-M under ultrasonic irradiation were also studied. Synchronous fluorescence spectra show that the binding and damage sites of Chl-M to BSA molecule are mainly on the tryptophan (Trp) residues. The generation of ROS in Chl-M sonodynamic process is estimated by the method of Oxidation-Extraction Spectrometry (OEP). This paper may offer some valuable references for the study of the sonodynamic activity of Chl-M and the effect of the central metals. Synchronously, it contributes to the application of Chl-M in SDT for tumor treatment.

Oxidation-extraction spectrometry of reactive oxygen species (ROS) generated by chlorophyllin magnesium (Chl-Mg) under ultrasonic irradiation.

In order to examine the mechanism and process of sonodynamic reaction, the chlorophyllin magnesium (Chl-Mg) acting as a sonosensitizer was irradiated by ultrasound, and the generation of reactive oxygen species (ROS) were detected by the method of oxidation-extraction spectrometry (OES). That is, under ultrasonic irradiation in the presence of Chl-Mg, the 1,5-diphenyl carbazide (DPCI) is oxidized by generated ROS into 1,5-diphenyl carbazone (DPCO), which can be extracted by mixed organic solvent and display a obvious visible absorption at 563 nm wavelength. Besides, the generation conditions of ROS were also reviewed. The results demonstrated that the quantities of generated ROS increased with the increase of ultrasonic irradiation time, Chl-Mg concentration and DPCI concentration. Finally, several radical scavengers (l-Histidine (His), 2,6-Di-tert-butyl-methylphenol (BHT) and Vitamin C (VC)) were used to determine the kind of the generated ROS. It was found that at least the hydroxyl radical (OH) and singlet oxygen (1O2) were generated in the presence of Chl-Mg under ultrasonic irradiation. It is wish that this paper might offer some valuable references for the study on the mechanism of SDT and the application of Chl-Mg in tumor treatment.

Spectroscopic analyses on interaction of Amantadine-Salicylaldehyde, Amantadine-5-Chloro-Salicylaldehyde and Amantadine-o-Vanillin Schiff-Bases with bovine serum albumin (BSA)

In this work, three Tricyclo [3.3.1.1(3,7)] decane-1-amine (Amantadine) Schiff-Bases, Amantadine-Salicylaldehyde (AS), Amantadine-5-Chloro-Salicylaldehyde (AS-5-C) and Amantadine-o-Vanillin (AS-o-V), were synthesized by direct heating reflux method in ethanol solution and characterized by infrared spectrum and elementary analysis. Fluorescence quenching was used to study the interaction of these Amantadine Schiff-Bases (AS, AS-5-C and AS-o-V) with bovine serum albumin (BSA). According to fluorescence quenching calculations the bimolecular quenching constant (K(q)), apparent quenching constant (K(SV)), effective binding constant (K(A)) and corresponding dissociation constant (K(D)), binding site number (n) and binding distance (r) were obtained. The results show that these Amantadine Schiff-Bases can obviously bind to BSA molecules and the binding strength order is AS<AS-5-C=AS-o-V. Synchronous fluorescence spectroscopy reveals that these Amantadine Schiff-Bases adopt different way to bind with BSA molecules. That is, the AS and AS-5-C are accessibility to tryptophan (Trp) residues more than the tyrosine (Tyr) residues, while the AS-o-V is equally close to the Tyr and Trp residues.

Synthesis and crystal structure of a 2-D yttrium coordination network with propylenediamine-N,N,N′,N′-tetraacetic acid

A 2-D binuclear coordination polymer, {[YIII(Hpdta)(H2O)]2 · 6H2O} n (H4pdta = propylenediamine-N,N,N′,N′-tetraacetic acid), has been synthesized through direct hydrothermal reaction and characterized by infrared spectrum and thermal analysis. Single-crystal X-ray diffraction reveals that Y(III) is eight-coordinate of almost standard square antiprismatic polyhedron.

Synthesis and structural determination of a novel complex [YbIII(HEgta)] · 4H2O in comparison with [YbIII(HEgta)] · 2H2O

One novel ytterbium complex [YbIII(HEgta)] · 4H2O (I), where H4Egta = ethylene glycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid, has successfully been synthesized by the reaction of Yb2O3 with H4Egta in an aqueous solution after refluxing for 18 h. The crystal and molecular structures were determined by the infrared spectrum and X-ray crystallography. The crystal structural analysis reveals that central Yb(III) in I is eight-coordinated in a geometry of pseudo-square antiprismatic polyhedron by two amine N atoms, two ethylene glycol O atoms, and four carboxyl O atoms from one HEgta ligand and crystallizes in the orthorhombic crystal system with P212121 space group. The crystal data are as follows: a = 9.4927(8), b = 12.2627(13), c = 18.3657(17) Å, V=2137.9(4) Å3, Z = 4, ρcalcd = 1.934 mg/m3, μ = 4.448 mm−1, F(000) = 1236, R = 0.0291, and wR = 0.0714 for 8850 observed reflections with I ≥ 2σ(I). In addition, there is a protonated coordinated carboxyl O atom (O(5)) in the [YbIII(HEgta)] moiety.