Xudong Jin

Detection and analysis of reactive oxygen species (ROS) generated by nano-sized TiO2 powder under ultrasonic irradiation and application in sonocatalytic degradation of organic dyes

Recently, the sonocatalytic technology using various semiconductors combined with ultrasonic irradiation has been received much attention to solve the environmental problems. In this paper, nano-sized titanium dioxide (TiO(2)) powder as a sonocatalyst was irradiated by ultrasound and the generation of reactive oxygen species (ROS) during sonocatalytic reaction process has been estimated by the method of Oxidation-Extraction Photometry (OEP). That is, the 1,5-diphenylcarbohydrazide (DPCI) can be oxidized by ROS into diphenylcarbonzone (DPCO), which can be extracted by the mixed solution of benzene and carbon tetrachloride and show the great absorbance at 563 nm wavelength. The synergistic effect of TiO(2) and ultrasonic irradiation was estimated and some influencing factors, such as ultrasonic irradiation time and TiO(2) addition amount on the generation of ROS were reviewed. The results indicate that the quantities of generated ROS increase with the increase of ultrasonic irradiation time and TiO(2) addition amount. Moreover, the relationship between quantities of generated ROS and DPCI concentration was also studied. And then, several quenchers were used to determine the kind of the generated ROS. At last, the researches on the sonocatalytic degradation of organic dyes and the corresponding reaction kinetics have also been performed, which is found to follow the pseudo first-order kinetics approximately. This paper may offer some important subjects for broadening the applications of sonocatalytic technology.

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.

Spectroscopic analyses on interaction of o-Vanillin-d-Phenylalanine, o-Vanillin-l-Tyrosine and o-Vanillin-l-Levodopa Schiff Bases with bovine serum albumin (BSA)

In this work, three o-Vanillin Schiff Bases (o-VSB: o-Vanillin-D-Phenylalanine (o-VDP), o-Vanillin-L-Tyrosine (o-VLT) and o-Vanillin-L-Levodopa (o-VLL)) with alanine constituent were synthesized by direct reflux method in ethanol solution, and then were used to study the interaction to bovine serum albumin (BSA) molecules by fluorescence spectroscopy. Based on the fluorescence quenching calculation, the bimolecular quenching constant (K(q)), apparent quenching constant (K(sv)), effective binding constant (K(A)) and corresponding dissociation constant (K(D)) as well as binding site number (n) were obtained. In addition, the binding distance (r) was also calculated according to Fosters non-radioactive energy transfer theory. The results show that these three o-VSB can efficiently bind to BSA molecules, but the binding array order is o-VDP-BSA>o-VLT-BSA>o-VLL-BSA. Synchronous fluorescence spectroscopy indicates that the o-VDP is more accessibility to tryptophan (Trp) residues of BSA molecules than to tyrosine (Tyr) residues. Nevertheless, the o-VLT and o-VLL are more accessibility to Tyr residues than to Trp residues.

Detection and comparison of reactive oxygen species (ROS) generated by chlorophyllin metal (Fe, Mg and Cu) complexes under ultrasonic and visible-light irradiation

In this paper, in order to examine the mechanisms of sonodynamic and photodynamic reactions, the chlorophyllin metal (Chl-M (M=Fe, Mg and Cu)) complexes were irradiated by ultrasound (US) and visible-light (VL), respectively, and the generation of reactive oxygen species (ROS) were detected by the method of Oxidation-Extraction Spectrometry (OES). That is, the 1,5-diphenyl carbazide (DPCI) is oxidized by the generated ROS into 1,5-diphenyl carbazone (DPCO), which can display a various visible absorption around 563 nm wavelength. Besides, some influence parameters on the generation of ROS were also reviewed. The results demonstrated an apparent synergistic effect of Chl-M and ultrasonic or visible-light irradiation for the generation of ROS. Moreover, the quantities of generated ROS increase with the increase of (ultrasonic or visible-light) irradiation time and Chl-M (M=Fe, Mg and Cu) concentration. Finally, several quenchers were used to determine the kind of the generated ROS. It is wished that this paper might offer some valuable references for the study on the sonodynamic therapy (SDT) and photodynamic therapy (PDT) mechanisms and the application of Chl-M in tumor treatment.

Spectroscopic investigation on assisted sonocatalytic damage of bovine serum albumin (BSA) by metronidazole (MTZ) under ultrasonic irradiation combined with nano-sized ZnO

The previous work proved that the bovine serum albumin (BSA) could be damaged under the combined action of ultrasonic irradiation and ZnO. In this work, the assisted sonocatalytic damage of BSA using metronidazole (MTZ) as a sensitizer was further investigated by means of UV-vis and fluorescence spectra. The results indicated that the adding of MTZ could obviously promote the sonocatalytic damage of BSA under ultrasonic irradiation in the presence of nano-sized ZnO powder. Furthermore, it was found that the damage degree of BSA was aggravated by some influencing factors except ionic kind and strength. In addition, the damage site of BSA was also studied with synchronous fluorescence technology. It was found that the damage site was mainly at tryptophan (Trp) residue.

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.

Syntheses, structural determination and binding studies of nine-coordinate mononuclear (EnH2)1.5 [ErIII(Ttha)] · 3H2O and (EnH2)[ErIII(Egta)(H2O)]2 · 6H2O

In this work, the title complexes, (EnH2)1.5[ErIII(Ttha)] · 3H2O (I) and (EnH2)[ErIII(Egta)(H2O)]2 · 6H2O (II), where En = ethylenediamine, H6Ttha = triethylenetetramine-N,N,N′,N″,N″’,N″′-hexaacetic acid, H4Egta = ethyleneglycol-bis-(2-aminoethylether)-N,N,N′,N′-tetraacetic acid, have been successfully synthesized. Their structures have been characterized by IR spectroscopy and single-crystal X-ray diffraction techniques. The X-ray diffraction reveals that I is nine-coordinated and crystallizes in the monoclinic crystal space group P2/n with cell dimensions a = 17.6058(16), b = 9.6249(9), c = 20.560(2) Å, β = 109.7440(10)°, and V = 3279.1(5) Å3. Compound II is also nine-coordinated and crystallizes in the monoclinic crystal space group P21/n with the cell dimensions a = 12.938(6), b = 12.651(5), c = 14.943(6) Å, β = 105.441(5)°, and V = 2357.5(17) Å3. In I, each EnH22+ cation connects three adjacent [ErIII(Egta)(H2O)]− complex anions through hydrogen bonds, while in I, there are two types of EnH22+ anions. One is highly symmetrical, forming hydrogen bonds with two neighboring [ErIII(Ttha)]3− complex anions. The other anion connects three adjacent [ErIII(Ttha)]3− complex anions through hydrogen bonds. These hydrogen bonds lead to the formation of 2D ladder-like layer structure.