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1.
Int J Mol Sci ; 24(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36613814

RESUMO

Effective capture and safe disposal of radioactive iodine (129I or 131I) during nuclear power generation processes have always been a worldwide environmental concern. Low-cost and high-efficiency iodine removal materials are urgently needed. In this study, we synthesized two aniline-based hypercrosslinked polymers (AHCPs), AHCP-1 and AHCP-2, for iodine capture in both aqueous and gaseous phases. They are obtained by aniline polymerization through Friedel-Crafts alkylation and Scholl coupling reaction, respectively, with high chemical and thermal stability. Notably, AHCP-1 exhibits record-high static iodine adsorption (250 wt%) in aqueous solution. In the iodine vapor adsorption, AHCP-2 presents an excellent total iodine capture (596 wt%), surpassing the most reported amorphous polymer adsorbents. The rich primary amine groups of AHCPs promote the rapid physical capture of iodine from iodine water and iodine vapor. Intrinsic features such as low-cost preparation, good recyclability, as well as excellent performance in iodine capture indicate that the AHCPs can be used as potential candidates for the removal of iodine from radioactive wastewater and gas mixtures.


Assuntos
Iodo , Compostos de Anilina , Gases , Radioisótopos do Iodo , Polímeros , Água
2.
J Am Chem Soc ; 142(15): 7218-7224, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32212652

RESUMO

Hydrogen-bonded organic frameworks (HOFs) show great potential in many applications, but few structure-property correlations have been explored in this field. In this work, we report that self-assembly of a rigid and planar ligand gives rise to flat hexagonal honeycomb motifs which are extended into undulated two-dimensional (2D) layers and finally generate three polycatenated HOFs with record complexity. This kind of undulation is absent in the 2D layers built from a very similar but nonplanar ligand, indicating that a slight torsion of ligand produces overwhelming structural change. This change delivers materials with unique stepwise adsorption behaviors under a certain pressure originating from the movement between mutually interwoven hexagonal networks. Meanwhile, high chemical stability, phase transformation, and preferential adsorption of aromatic compounds were observed in these HOFs. The results presented in this work would help us to understand the self-assembly behaviors of HOFs and shed light on the rational design of HOF materials for practical applications.

3.
Mol Reprod Dev ; 84(12): 1257-1270, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29024157

RESUMO

Nonylphenol (NP) is an environmental chemical that affects apoptosis and male infertility. In our study, we found that a high concentration of NP could down-regulate the expression of microRNA-361-3p (miR-361-3p) in the murine GC-1 spermatogonia cell line and in vivo in murine spermatogonia. Additionally, one direct target of this miR, the 3' untranslated region of Killin (Klln) mRNA, was identified. Klln encodes a transcription factor that directly regulates the expression of Tp73 (transcriptionally active p73), whose encoded protein can up-regulate the expression of Puma (p53 upregulated modulator of apoptosis). Thus, our investigation revealed that the expression of Klln, Tp73, and Puma increased upon NP-dependent down-regulation of miR-361-3p, which eventually leads to apoptosis of spermatogonia.


Assuntos
Apoptose/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , MicroRNAs/biossíntese , Fenóis/toxicidade , Espermatogônias/metabolismo , Regiões 3' não Traduzidas , Animais , Apoptose/genética , Proteínas Reguladoras de Apoptose/biossíntese , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular , Masculino , Camundongos , MicroRNAs/genética , Espermatogônias/patologia , Proteína Tumoral p73/biossíntese , Proteína Tumoral p73/genética , Proteínas Supressoras de Tumor/biossíntese , Proteínas Supressoras de Tumor/genética
4.
Colloids Surf B Biointerfaces ; 222: 113114, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36577345

RESUMO

The monodisperse double emulsions obtained by microfluidic method can serve as ideal templates for preparing core-shell alginate microcapsules, which have attracted much attention in biological applications, such as drug delivery systems and cell encapsulation, tissue engineering. However, the formation behavior and dynamic analysis of double emulsion with an alginate shell is still unclear due to the complex rheological behavior of alginate solutions. Herein, we employ a dual-coaxial microfluidic device to generate the high-quality double emulsion droplets with alginate shell, focusing on the effects of the fluid properties of alginate solution in the middle phase (viscosity, µm) and the fluid flow rate on the droplet formation mechanism. As the viscosity of the middle fluid (µm) increased, the size of compound droplets (D2) increased and the size of inner droplets (D1) decreased, and the break-up regimes occurred a dripping-to-jetting transition when µm = 160 mPa s. The number of encapsulated inner droplets can be predicted and precisely controlled by regulating the generation frequency of inner (f1) and outer droplets (f2). The breakup dynamics of the alginate thread are also analyzed by using the volume-of-fluid/continuum-surface-force (VOF/CSF) method. The results show that the pressure and velocity in the neck of pinch-off is lower in the jetting than that in the dripping regime. This study will provide useful guidance for the rational design and controllable preparation of core-shell alginate microcapsules.


Assuntos
Alginatos , Microfluídica , Microfluídica/métodos , Emulsões , Cápsulas , Reologia
5.
Environ Sci Pollut Res Int ; 30(6): 16398-16407, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36181599

RESUMO

In this study, ferric chloride and sulfuric acid were used to increase the Fe-containing minerals on the biochar surface before a pyrolysis at 600 °C. The pristine and Fe-modified biochars prepared at different concentrations of sulfuric acid (50FBC and 72FBC) were characterized and analyzed, and their capacity of As(V) adsorption under various pH and ionic strength were evaluated. The results showed that the maximum adsorption capacities of As(V) calculated by the Langmuir model for 50FBC and 72FBC are 10.33 and 15.61 mg g-1, respectively, which are enhanced by 5.0 and 7.8 times compared with the pristine biochar. The higher dosage of H2SO4 (72%) used in the modification leads to a better adsorption capacity of As, especially under neutral to alkaline conditions (7.0 < pH < 10.0). It might result from the increased amounts of Fe-containing minerals formed on the biochar surface, and the enriched functional groups such as phenolic hydroxyl and carboxyl, resulting in the resistance to alkaline conditions. Overall, the Fe-modified biochar, especially 72FBC, had good potential as an environmentally friendly adsorbent for removing As from contaminated water under a wider pH range.


Assuntos
Arsênio , Poluentes Químicos da Água , Adsorção , Carvão Vegetal/química , Poluentes Químicos da Água/química
6.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): o1098, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589959

RESUMO

In the title compound, C(10)H(11)NO(4)·H(2)O, the carboxyl group is twisted at a dihedral angle of 6.1 (3)° with respect to the benzene ring. In the crystal, the organic mol-ecules are linked by pairs of O-H⋯O hydrogen bonds involving both carboxyl groups, forming zigzag chains propagating along the b-axis direction. The water mol-ecules form [100] chains linked by O-H⋯O hydrogen bonds. The organic mol-ecule and water chains are cross-linked by N-H⋯O(water) and O(water)-H⋯O hydrogen bonds, generating (001) sheets.

7.
J Healthc Eng ; 2022: 4733329, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35299689

RESUMO

To investigate the efficacy of super-mini-PCNL (SMP) and ureteroscopy in kidney stone (KS) sufferers and learn the risk factors of postoperative infection. A retrospective analysis was performed on 180 KS sufferers who were diagnosed and treated in our hospital from May 2019 to May 2021. They were enrolled into an observation group (OG, n = 104) and a control group (CG, n = 76) based on different treatment methods. Therein, the former was treated with SMP, while the latter was treated with ureteroscopy. The operation time, blood loss, hospital stay, recent stone-free rate (one week after operation), changes of serum creatinine (SCr), blood urea nitrogen (BUN), and cystatin C (CysC) levels before and after operation and complications were compared. Those sufferers were assigned to infected and uninfected groups based on their postoperative infection. The risk factors were assessed through logistic regression, and the model formula was established. The predictive value of this model for infection was tested through RO. Compared with CG, the operation time of the OG was longer, the blood loss and hospital stay were lower (P < 0.05), and the stone-free rate was higher (P < 0.05). Renal function indexes before and after treatment (P > 0.05) and postoperative complications revealed no significant difference (P > 0.05). Logistic regression analysis manifested that preoperative urinary tract infection (OR: 4.690, 95% CI: 1.170-18.802), preoperative blood glucose level (OR: 11.188, 95% CI: 2.106-59.442), positive urine culture (OR: 10.931, 95% CI: 2.453-48.705), and infectious stones (OR: 3.951, 95% CI: 1.020-15.300) were independently related to infection. The risk prediction equation is logit(p)=-8.913+1.545 × X1+2.415 × X2+2.392 × X3+1.374 × X4, with a goodness-of-fit value of 0.545. The AUC is 0.930, so SMP is superior to ureteroscopy in KS sufferers. Preoperative urinary tract infection, preoperative blood glucose level, positive urine culture, and infectious stones are independently related to infection.


Assuntos
Cálculos Renais , Infecções Urinárias , Glicemia , Feminino , Humanos , Cálculos Renais/cirurgia , Masculino , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Ureteroscopia/efeitos adversos , Ureteroscopia/métodos , Infecções Urinárias/etiologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-36612648

RESUMO

Iron-modified biochar can be used as an environmentally friendly adsorbent to remove the phosphate in wastewater because of its low cost. In this study, Fe-containing materials, such as zero-valent iron (ZVI), goethite, and magnetite, were successfully loaded on biochar. The phosphate adsorption mechanisms of the three Fe-modified biochars were studied and compared. Different characterization methods, including scanning electron microscopy/energy-dispersive spectrometry (SEM-EDS), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS), were used to study the physicochemical properties of the biochars. The dosage, adsorption time, pH, ionic strength, solution concentration of phosphate, and regeneration evaluations were carried out. Among the three Fe-modified biochars, biochar modified by goethite (GBC) is more suitable for phosphate removal in acidic conditions, especially when the pH = 2, while biochar modified by ZVI (ZBC) exhibits the fastest adsorption rate. The maximum phosphate adsorption capacities, calculated by the Langmuir-Freundlich isothermal model, are 19.66 mg g-1, 12.33 mg g-1, and 2.88 mg g-1 for ZBC, GBC, and CSBC (biochar modified by magnetite), respectively. However, ZBC has a poor capacity for reuse. The dominant mechanism for ZBC is surface precipitation, while for GBC and CSBC, the major mechanisms are ligand exchange and electrostatic attraction. The results of our study can enhance the understanding of phosphate removal mechanisms by Fe-modified biochar and can contribute to the application of Fe-modified biochar for phosphate removal in water.


Assuntos
Fosfatos , Poluentes Químicos da Água , Fosfatos/química , Óxido Ferroso-Férrico , Poluentes Químicos da Água/química , Carvão Vegetal/química , Ferro/química , Água , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(12): 3343-6, 2010 Dec.
Artigo em Zh | MEDLINE | ID: mdl-21322236

RESUMO

A novel ligand(L), (N, N'-bis (4-methylbenzyl) ethane-1, 2-diamine), and its transition metal(II) complex, [ML2 (H2O)2]2+ x 2NO3- (M = Cu(II), Co(II, Ni(II), Zn(II)), have been synthesized and characterized by elemental analysis, IR and 1H NMR. The crystal structure of the Cu-L complex was characterized by X-ray single crystal diffraction, and the results showed a regular octahedral structure in which each metal ion is six--coordinated with four nitrogen atoms from two ligands and two oxygen atoms from two water molecules. The interaction of the complex with calf thymus DNA was investigated by UV spectroscopy and fluorescence spectroscopy, and the results suggest that the complex binds to DNA by electrostatic interaction mode. The binding constant(Cu-L, Co-L, Ni-L, Zn-L) was 1.67 x 10(3), 2.5 x 10(3), 1.35 x 10(3) and 9.85 x 10(2), respectively.


Assuntos
Cobre , DNA/química , Elementos de Transição , Aminas , Animais , Bovinos , Cristalografia por Raios X , Ligantes , Metais , Espectrometria de Fluorescência
10.
Dalton Trans ; 49(7): 2308-2316, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32016190

RESUMO

Heteroatom-doped graphene quantum dots (GQDs) have attracted considerable attention due to their potential applications as luminescent materials and in biology. In this work, we developed a solvent-free gram-scale mechanochemical method for the preparation of nitrogen-doped graphene quantum dots (N-GQDs) with the highest solubility (31 mg mL-1) in water reported to date. Commercial graphite was sheared and cut through grinding with solid melamine and then ground with solid KOH to get sub-5 nm-sized, 1-3-layered N-GQDs. Notably, these N-GQDs exhibit white-light emission and broad excitation-dependent full-color photoluminescence from 463 nm to 672 nm. When the excitation light ranged from 325 nm to 485 nm, these mechanochemically obtained N-GQDs exhibited bright white-light emission. Intriguingly, the change in the emission wavelength has two-stage linear relationships with the change in the excitation wavelength, and the inflection point is at 580 nm (excited at 550 nm). The difference between the emission and excitation wavelengths decreases from 138 to 12 nm, which also shows two-stage linear relationships with the change in the excitation wavelength. It is notable that their PL quantum yields are high, up to 26.6%. Furthermore, we studied the inhibitory effect of as-obtained N-GQDs on bladder cancer cells (UMUC-3); as a result, with the increase of the concentration of N-GQDs, the proliferation of cancer cells was obviously prohibited.


Assuntos
Antineoplásicos/farmacologia , Grafite/farmacologia , Luz , Luminescência , Pontos Quânticos/química , Neoplasias da Bexiga Urinária/tratamento farmacológico , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Grafite/química , Humanos , Processos Fotoquímicos , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/patologia
11.
Chem Sci ; 11(8): 2141-2147, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34123303

RESUMO

We demonstrate a simple method for real-time monitoring of mechanochemical synthesis of metal-organic frameworks, by measuring changes in pressure of gas produced in the reaction. Using this manometric method to monitor the mechanosynthesis of the zeolitic imidazolate framework ZIF-8 from basic zinc carbonate reveals an intriguing feedback mechanism in which the initially formed ZIF-8 reacts with the CO2 byproduct to produce a complex metal carbonate phase, the structure of which is determined directly from powder X-ray diffraction data. We also show that the formation of the carbonate phase may be prevented by addition of excess ligand. The excess ligand can subsequently be removed by sublimation, and reused. This enables not only the synthesis but also the purification, as well as the activation of the MOF to be performed entirely without solvent.

12.
J Am Chem Soc ; 131(20): 6894-5, 2009 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-19453189

RESUMO

The tetracarboxylate organic linker and Zn(II) ions assemble into chiral building blocks for a porous metal-organic framework with ferroelectric and second-order nonlinear optical properties.

13.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 4): m471, 2009 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-21582401

RESUMO

In the title compound, [Zn(2)(C(22)H(36)NS(2))(4)], two bidentate dithio-carbamate groups chelate directly to the Zn(II) atoms, whereas the two remaining dithio-carbamate ligands bridge the Zn atoms via a crystallographic inversion centre. The Zn atoms show a strongly distorted tetra-hedral geometry. Adding the long S⋯S distance with the inversion centre being in the middle, the resulting five-coordinate geometry around the Zn atoms can be considered to be between distorted recta-ngular pyramidal and trigonal bipyramidal, with a calculated τ value of 0.31. In this dimer complex, two inversion-related tetra-decyl carbon chains exhibit all-trans conformations, and the other two chains show a cis conformation at the end of the chains.

14.
Artigo em Inglês | MEDLINE | ID: mdl-18061534

RESUMO

A new tripodal, hydroxyl-rich ligand, tris(2-[(3,4-dihydroxybenzylidene)imino]ethyl)amine (L), and its complexes with lanthanide nitrates were synthesized. These complexes which are stable in air with the general formula of [LnL(NO3)2]NO3.H2O (Ln=La, Sm, Eu, Gd, Y) were characterized by molar conductivity, elemental analysis, IR spectra and thermal analysis. The NO3(-) groups coordinated to lanthanide mono-dentately, and the coordination number in these complexes may be 8. The interaction of complexes with DNA were investigated by ultraviolet and fluorescent spectra, which showed that the binding mode of complexes with DNA was intercalation, and the binding affinity with DNA were La(III) complex>Sm(III) complex>Eu(III) complex>Gd(III) complex>Y(III) complex. Based on these results, it can be shown that the La(III)complex is promising candidate for therapeutic reagents and DNA probes.


Assuntos
Compostos de Benzil/química , DNA/química , Etilaminas/química , Elementos da Série dos Lantanídeos/química , Nitratos/química , Ligantes , Estrutura Molecular , Solubilidade , Espectrometria de Fluorescência , Temperatura
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(2): 374-9, 2008 Feb.
Artigo em Zh | MEDLINE | ID: mdl-18479026

RESUMO

Four sulfur-contained D(+)-glucosamine metal complexes were synthesized (M-GLUS, M = Co, Cu, Ni and Zn)and characterized by elementary analysis, molar conductance, and proton nuclear magnetic resonance. The yield of the complex was about 70%, and it dissolved easily in water. The ligand coordinates with metalions mainly between sulphur and metalions, the coordination molar ratio of the ligand to metalion was 2 : 1, and the molar conductivity indicated that all the complexes are nonelectrolyte. The mechanism of the interaction between metal complexes and calf thymus (ct) DNA in Tris buffer (pH = 7. 08), was studied by ultraviolet absorption and fluorescence spectroscopy. The results from varied experiments showed that the intensity of the maximal absorption peaks increased with gradual addition of metal complexes, but the metalions can decrease the maximal absorption and the ligand has no effect on it. Meanwhile, metal complexes could remarkably quench the emission intensity of the DNA-EB system, and the metal complexes could be bound to ct DNA. The quenching mechanism was discussed by Stern-Volmer's equation, the figure showed that it is influenced by static quenching and dynamic quenching, so the partial interaction of the complexes and ct DNA was the major mode. Under physiological pH condition, this study was designed to examine the effect of complexes on human serum albumin and bovine serum albumin by fluorescence. The binding constants and sites of the interaction with SA were analyzed by the Scatchard's equation, the results indicated that there was a strong interaction between the four metal complexes and serum albumin and the binding force was Co-GLUS > Zn-GLUS > Cu-GLUS > Cu-GLUS, and the binding site is only one.


Assuntos
DNA/química , Glucosamina/química , Metais Pesados/química , Albumina Sérica/química , Compostos de Enxofre/química , Animais , Bovinos , Humanos , Concentração de Íons de Hidrogênio , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Compostos de Enxofre/síntese química
16.
Dalton Trans ; 47(14): 5065-5071, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29561003

RESUMO

The use of salts as grinding media to assist the mechanosynthesis, and the following one-pot mechanochemical post-synthesis, of hierarchically porous MOFs was carried out efficiently by ball milling. NaCl or KCl were used as a solid solvent to initially pre-grind with 1,3,5-benzenetricarboxylic acid (H3BTC) and copper acetate monhydrate, respectively, for 1 minute, then both mixtures were combined together for a further 20 minutes of grinding, and the resultant mixture was finally washed with ethanol and water to obtain the hierarchically micro-, meso- and macroporous HKUST-1 with a high yield. Moreover, the post-synthesis of these as-obtained hierarchically porous HKUST-1 was easily performed via grinding triethylenediamine (TED) with the above unwashed crude-products for 20 minutes. By adjusting the amount of NaCl and TED added, we simply fabricated the pore- and function-adjustable hierarchically porous HKUST-1. Furthermore, these as-obtained HKUST-1 products showed high performance in the capture of volatile iodine.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(12): 2550-2, 2007 Dec.
Artigo em Zh | MEDLINE | ID: mdl-18330307

RESUMO

The interaction between Fe3(CO)12 and DNA was investigated by absorption and spectra, fluorescence spectra. The absorption of EB-DNA system in the presence of Fe3 (CO)12 showed that Fe3(CO)12 could partly sustain the place of EB. The result of fluorescence spectra suggested that Fe3(CO)12 could enhance the fluorescence intensity of DNA sharply. All the experimental results indicated that the intercalative binding mode was the major model for the interaction of Fe3(CO)12 cluster complex with DNA.


Assuntos
DNA/química , Compostos Férricos/química , Etídio/química , Conformação de Ácido Nucleico , Espectrometria de Fluorescência
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 65(3-4): 912-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16914368

RESUMO

Three new aryl amide type ligands, N-(phenyl)-2-(quinolin-8-yloxy)acetamide (L(1)), N-(benzyl)-2-(quinolin-8-yloxy)acetamide (L(2)) and N-(naphthalene-1-yl)-2-(quinolin-8-yloxy)acetamide (L(3)) were synthesized. With these ligands, three series of lanthanide(III) complexes were prepared: [Ln(L(1))(2)(NO(3))(2)]NO(3), [Ln(L(2))(2)(NO(3))(2)(H(2)O)(2)]NO(3).H(2)O and [Ln(L(3))(2)(NO(3))(2)(H(2)O)(2)]NO(3).H(2)O (Ln=La, Sm, Eu, Gd). The complexes were characterized by the elemental analyses, molar conductivity, (1)H NMR spectra, IR spectra and TG-DTA. The fluorescence properties of complexes in the solid state and the triplet state energies of the ligands were studied in detail, respectively. It was found that the Eu(III) complexes have bright red fluorescence in solid state. The energies of excited triplet state for the three ligands are 20325 cm(-1) (L(3)), 21053 cm(-1) (L(2)) and 22831 cm(-1) (L(1)), respectively. All the three ligands sensitize Eu(III) strongly and the order of the emission intensity for the Eu(III) complexes with the three ligands is L(3)>L(2)>L(1). It can be explained by the relative energy gap between the lowest triplet energy level of the ligand (T) and (5)D(1) of Eu(III). This means that the triplet energy level of the ligand is the chief factor, which dominates Eu(III) complexes luminescence.


Assuntos
Acetamidas/química , Compostos de Benzil/química , Elementos da Série dos Lantanídeos/química , Naftalenos/química , Compostos Organometálicos/química , Quinolinas/química , Análise Espectral , Acetamidas/síntese química , Compostos de Benzil/síntese química , Fluorescência , Ligantes , Naftalenos/síntese química , Quinolinas/síntese química
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 26(7): 1298-302, 2006 Jul.
Artigo em Zh | MEDLINE | ID: mdl-17020044

RESUMO

The mechanism of the interaction between hydrazide-podophyllic (HDPP) metal (Me) complexes and calf thymus (ct) DNA in Tris buffer (pH 7.08) was studied by viscosity measurements, electronic absorption, gel electrophoresis, and ethidium bromide (EB) fluorescence spectroscopy. The results from varied experiments show that the intensity of the maximal absorption peaks from absorption spectra is weakened in the presence of DNA compared with that in the absence of DNA. Meanwhile, DNA can remarkably quench the emission intensity of the complex Me-HDPP system. The Me-HDPP complexes can increase the viscosity of ct DNA slightly and catalyze the cleavage of super coiled pBR322 DNA to the nicked form. The complexes of Ni-HDPP and Co-HDPP can be bound to ct DNA mainly by interaction, while the partial interaction of Zn-HDPP and ct DNA is the major modes. The binding constant of Me-HDPP complexes with ct DNA was determined.


Assuntos
DNA/química , DNA/metabolismo , DNA Super-Helicoidal/química , Hidrazinas/química , Plasmídeos/química , Podofilina/química , Espectrometria de Fluorescência
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