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1.
Chemosphere ; 250: 126262, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32114342

RESUMO

As an attractive alternative to radioactive cesium removal, we introduced an adsorptive filtration method using a composite membrane consisting of potassium copper hexacyanoferrate (KCuHCF) and graphene-based support. Polyethyleneimine-grafted reduced graphene oxide (PEI-rGO), used as an immobilizing matrix, was effective not only in distributing KCuHCF inside the composite with the aid of abundant amino-functionality, but also in achieving high water flux by increasing the interlayer spacing of the laminar membrane structure. Due to the rapid and selective cesium adsorption properties of KCuHCF, the fabricated membrane was found to be effective in achieving complete removal of cesium ions under a high flux (over 500 L m-2 h-1), which is difficult in a conventional membrane utilizing the molecular sieving effect. This approach offers strong potential in the field of elimination of radionuclides that require rapid and complete decontamination.


Assuntos
Césio/química , Ferrocianetos/química , Grafite/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Adsorção , Cobre/química , Filtração , Polietilenoimina/química , Potássio , Água
2.
Anal Bioanal Chem ; 412(8): 1769-1784, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32043201

RESUMO

Simultaneous speciation of benzenediol isomers (BDIs), 1,2-benzenediol (catechol, CC), 1,3-benzenediol (resorcinol, RS), and 1,4-benzenediol (hydroquinone, HQ), was investigated by differential pulse voltammetry (DPV) using a graphite paste electrode (GPE) modified with Prussian blue-polyaniline nanocomposite. The modified GPE showed good stability, sensitivity, and selectivity properties for all the three BDIs. Prussian blue-doped nanosized polyaniline (PBNS-PANI) was synthesized first by using mechanochemical reactions between aniline and ferric chloride hexahydrate as the oxidants and then followed by the addition of potassium hexacyanoferrate(II) in a solid-state and template-free technique. The material was characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The DPV measurements are performed in phosphate electrolyte solution with pH 4.0 at a potential range of - 0.1 to 1.0 V. The proposed modified electrode displayed a strong, stable, and continuous three well-separated oxidation peaks towards electrooxidation at potentials 0.20, 0.31, and 0.76 V for HQ, CC, and RS, respectively. The calibration curves were linear from 1 to 350.5 µM for both HQ and CC, while for RS, it was from 2 to 350.5 µM. The limit of detection was determined to be 0.18, 0.01, and 0.02 µM for HQ, CC, and RS, respectively. The analytical performance of the PBNS-PANI/GPE has been evaluated for simultaneous determination of HQ, CC, and RS in creek water, commercial hair dye, and skin whitening cream samples with satisfactory recoveries between 90 and 106%. Overall, we demonstrated that the presence of NS-PANI and PB resulted in a large redox-active surface area that enabled a promising analytical platform for simultaneous detection of BDIs. Graphical abstract.


Assuntos
Compostos de Anilina/química , Derivados de Benzeno/análise , Ferrocianetos/química , Nanoestruturas/química , Derivados de Benzeno/química , Calibragem , Eletrodos , Humanos , Concentração de Íons de Hidrogênio , Isomerismo , Cinética , Limite de Detecção , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Anal Bioanal Chem ; 412(8): 1933-1946, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32076788

RESUMO

Biogenic amine biosensors, based on screen-printed carbon electrodes (SPCE) modified with Prussian blue (PB) and indium tin oxide nanoparticles (ITONP), are reported. PB/ITONP-modified SPCE was further modified with diamine oxidase (DAO) or monoamine oxidase (MAO) enzymes to construct the biosensors. The morphology of the modified electrodes was studied by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and atomic force microscopy (AFM). Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to enlighten the electrochemical properties of the modified electrodes at each step of biosensor fabrication. Electrode surface composition and experimental conditions were optimized and analytical performance characteristics of the biosensors were studied. Several biogenic amines were tested and both biosensors responded to histamine, putrescine and cadaverine. DAO/ITONP/PB/SPCE biosensor exhibited the highest response to histamine 6.0 × 10-6-6.9 × 10-4 M with a sensitivity of 1.84 µA mM-1. On the other hand, the highest sensitivity was obtained for cadaverine with the MAO/ITONP/PB/SPCE biosensor. The analytical utility of the presented biosensors were illustrated by the determination of cadaverine and histamine in cheese sample.


Assuntos
Amina Oxidase (contendo Cobre)/química , Aminas Biogênicas/análise , Técnicas Eletroquímicas/instrumentação , Eletrodos , Ferrocianetos/química , Nanopartículas Metálicas/química , Monoaminoxidase/química , Compostos de Estanho/química , Técnicas Biossensoriais
4.
Chemosphere ; 244: 125589, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050353

RESUMO

Radioactive Cs ions are extremely harmful to the human body, causing cancers and other diseases. Treatments were performed on radioactive Cs present in wastewater after use in industrial or medical fields. Prussian blue (PB) has been widely used for the removal of Cs ions from water but its colloidal structure hinders reuse, making it problematic for practical use. To solve this problem, we used a commercial macroporous polymer resin as a PB matrix. To provide an efficient anchor for PB, the surface of the polymer resin was decorated with sodium dodecylbenzenesulfonate to produce a negatively charged surface. The successful chemical binding between the polymer resin and PB prevented leakage of the latter during adsorption and crosslinked structure of the matrix provided regeneration of the adsorbent. The adsorbent maintained its removal efficiency after five repeats of the regeneration process. The PB-based, Cs ion-exchange resin showed excellent selectivity toward Cs ions and good reusability, maintaining its high adsorption capacity.


Assuntos
Benzenossulfonatos/química , Césio/química , Ferrocianetos/química , Resinas de Troca Iônica/química , Poluentes Químicos da Água/química , Adsorção , Humanos , Águas Residuárias/química , Purificação da Água
5.
Anal Chim Acta ; 1097: 169-175, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-31910957

RESUMO

In this work, a label-free electrochemical immunosensor was developed for the detection of procalcitonin (PCT), using toluidine blue functionalized NiFe Prussian-blue analog nanocubes (NiFe PBA nanocubes@TB) as a signal amplifier. NiFe PBA nanocubes was synthesized by a simple and efficient self-templating method in this work. NiFe PBA nanocubes with open-framework construction not only provides a larger specific area to load a mass of antibodies but produces an excellent signal without adding extra reaction reagent. Besides, the electrochemical performance of NiFe PBA nanocubes can be enhanced after functionalized with TB. The developed immunosensor exhibited favorable performance for PCT detection with a linear range from 0.001 to 25 ng mL-1 and a detection limit of 3 × 10-4 ng mL-1. Moreover, the immunosensor with acceptable reproducibility, selectivity, and stability may provide a new strategy in the clinical detection of PCT.


Assuntos
Ferrocianetos/química , Imunoensaio , Ferro/química , Nanocompostos/química , Níquel/química , Pró-Calcitonina/análise , Cloreto de Tolônio/química , Técnicas Biossensoriais , Técnicas Eletroquímicas , Humanos , Tamanho da Partícula , Propriedades de Superfície
6.
Chemosphere ; 247: 125919, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31978660

RESUMO

This study proposes the use of an aluminum-based drinking water treatment residue (DWTR) to adsorb ferrocyanide. The batch tests and chemical characterization results showed that ferrocyanide adsorption increased as the pH, ion strength, and the solid and solution ratio decreased, and as the initial ferrocyanide concentration increased. The pseudo-first (R2 = 0.906) and pseudo-second-order (R2 = 0.966) kinetic models well described the adsorption kinetics, and the adsorption isotherm was also well fittted by Langmuir (R2 = 0.989) and Freundlich (R2 = 0.989) models. The calculated initial ferrocyanide adsorption rate by the pseudo-second-order kinetic model was 0.0190 mg-CN g-1 h-1, and the estimated maximum adsorption capacity determined by the Langmuir model was 20.9 mg-CN g-1. The main structure and elemental distributions showed nearly no change in DWTR after adsorption. Adsorption involved electrostatic interactions and ligand exchanges with Al in DWTR, as evidenced by the 1.40 eV increase in the Al binding energy after adsorption. Furthermore, ferrocyanide adsorption had a dual effect on the DWTR porosity (including both increase and decrease effect), resulting in a slight increase in the specific surface area and total pore volume of DWTR after adsorption. This dual effect was likely related to Fe present in ferrocyanide, which introduced new vacant sites on DWTR. Overall, recycled DWTR is a promising potential adsorbent for ferrocyanide.


Assuntos
Alumínio/química , Ferrocianetos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Reciclagem
7.
Anal Chim Acta ; 1094: 80-89, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761050

RESUMO

In this paper, a composite electrode of N,P-doped Mo2C@C/Prussian blue (PB)/graphite felt (N,P-Mo2C@C/PB/GF) was prepared by a simple method and used for sensitive and effective detection of dopamine (DA). N,P-doped Mo2C nanospheres were prepared by using phosphomolybdic acid (PMo12) as an initiator to promote the polymerization of polypyrrole. Such nanospheres were used to accelerate the deposition process of PB from K3[Fe(CN)6] and FeCl3 in solution. The N,P-Mo2C@C/PB nanohybrid was then anchored to GF in order to obtain the electrochemical sensor. Two linear ranges were extrapolated for dopamine detection: from 0.18 to 30 µmol L-1 with a sensitivity of 0.268 µA µmol-1, and from 30 to 280 µmol L-1 with a sensitivity of 0.045 µA µmol-1. The device showed a detection limit as low as 0.011 µmol L-1, an excellent selectivity to DA over common interfering analytes, and a favorable long-time stability. Finally, the sensor was used for quantitative analysis of DA in the 10-fold dilution of human serum (10%) and exhibited a satisfactory recovery.


Assuntos
Carbono/química , Dopamina/sangue , Ferrocianetos/química , Grafite/química , Molibdênio/química , Nanocompostos/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Ferrocianetos/síntese química , Humanos , Limite de Detecção , Nitrogênio/química , Fósforo/química , Reprodutibilidade dos Testes
8.
Chem Commun (Camb) ; 56(7): 1046-1049, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31868183

RESUMO

A new type of artificial giant liposome incorporating ion transport channels and using nanoparticles of metal organic frameworks was demonstrated. The micropores of Prussian blue nanoparticles served as ion transport channels between the outer and inner phases of liposomes.


Assuntos
Ferrocianetos/química , Nanopartículas/química , Lipossomas Unilamelares/metabolismo , Concentração de Íons de Hidrogênio , Hidróxidos/metabolismo , Transporte de Íons , Estruturas Metalorgânicas/química , Lipossomas Unilamelares/química
9.
Food Chem ; 308: 125590, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31644970

RESUMO

A novel fluorescent nanoprobe was for the first time developed for the efficient detection of ferrocyanide ions ([Fe(CN)6]4-) based on nitrogen (N), sulfur (S) and chlorine (Cl) co-doped carbon nanoparticles (N,S,Cl-CNPs). The N,S,Cl-CNPs were fabricated through a simple and ultrafast acid-base neutralization method. The sensing mechanism was based on the quenching effect of [Fe(CN)6]4- on the fluorescence emission of N,S,Cl-CNPs via dynamic interaction. The N,S,Cl-CNPs were found to show high selectivity and sensitivity towards [Fe(CN)6]4- detection with two good linear relationships were achieved in the concentration ranges of 0.01-1.0 µg/mL and 1.0-50.0 µg/mL, respectively, and the detection limits are as low as 3.3 and 21.8 ng/mL, respectively. The proposed fluorescence method was successfully applied for [Fe(CN)6]4- analyses in food samples with high accuracy. The results of this study indicate the great application prospects of N,S,Cl-CNPs for [Fe(CN)6]4- detection in complex food matrix.


Assuntos
Carbono/química , Ferrocianetos/análise , Nanopartículas , Cloro/química , Ferrocianetos/química , Fluorescência , Análise de Alimentos , Limite de Detecção , Nitrogênio/química , Espectrometria de Fluorescência/métodos , Enxofre/química
10.
Chemosphere ; 239: 124707, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31479912

RESUMO

Site soils with persistent cyanide compounds (primarily iron-cyanide complex) pose potential hazards to the environment and require remediation before redevelopment. This study evaluated the possibility of thermal treatment on remediation of cyanide-contaminated soils via batch heating experiments spanning a wide temperature range (200-500 °C). The change with operation variables of total cyanide and some reaction intermediates (e.g. CN-) was analyzed in order to elucidate the optimal variables that guarantee cyanide removal while generating no hazardous byproducts. Temperature, heating time and cyanide species have been found to be important parameters influencing removal/destruction of cyanide in soils. For soils bearing K3[Fe(CN)6] and K4[Fe(CN)6], a removal efficiency of >99.9% can be obtained with temperatures over 350 °C at 1 h, while for samples bearing Fe4[Fe(CN)6]3, a higher temperature (>450 °C) is needed to obtain an equivalent efficiency. During heating, the iron-cyanide complexes decomposed, releasing highly toxic free cyanides, which will subsequently be oxidized. However, a small percentage of free cyanide can always be detected as a result of incomplete oxidation, thus caution should be taken to minimize the accumulation of free cyanide during thermal treatment.


Assuntos
Cianetos/análise , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/análise , Temperatura , Cianetos/química , Poluição Ambiental/prevenção & controle , Ferrocianetos/análise , Ferrocianetos/química , Oxirredução , Poluentes do Solo/química
11.
Chemosphere ; 245: 125578, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31864058

RESUMO

Environmental levels of platinum group elements (PGEs) are rising due to emissions of vehicle catalytic converter (VCC) materials containing palladium, platinum and rhodium. When these PGE-containing VCC materials are exposed to soil and water, coordination complex formation with ligands present in the environment may mobilize PGEs into solution, particularly Pd. Road de-icing salt contains two ligands with high affinities for Pd2+: chloride (Cl-) from NaCl and cyanide (CN-) from ferrocyanide (Fe(CN)64-) anti-caking agents. Batch leaching studies of VCC materials were conducted with solutions representative of de-icer-contaminated road runoff at pH 8 and room temperature for 48 h. Ferrocyanide (FC) concentrations of 0 µM, 1 µM, 2 µM and 10 µM were tested with background electrolyte concentrations of 0.028 M NaCl (1000 mg/L Cl-) or 0.028 M NaClO4. Palladium release increased with FC concentration, ranging from 0.014 ± 0.002 µM Pd without FC to 5.013 ± 0.002 µM Pd at 10 µM FC. At 0 µM, 1 µM and 2 µM FC, chloride induced further Pd release, but had no effect at 10 µM FC. PHREEQC modeling predicted that the predominant species present in equilibrium with Pd(OH)2(s) were Pd(OH)20 and Pd(CN)42-, and that PdClx2-x complexes had only a minor effect on the total concentration of dissolved palladium. The effect of FC on Pd release was predicted but not the effect of Cl-, indicating possible kinetic control. Platinum was measured above limits of detection (LODs) only at 10 µM FC, and rhodium levels were below LODs, consistent with their slower complexation kinetics.


Assuntos
Ferrocianetos/química , Paládio/química , Emissões de Veículos/análise , Catálise , Cloretos/química , Cloro , Monitoramento Ambiental , Platina/química , Ródio/análise , Solo/química
12.
Mikrochim Acta ; 187(1): 5, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31797120

RESUMO

An impedimetric single-shot assay is described for the determination of the proteinic breast cancer marker MUC1. The surface of a glassy carbon electrode was modified with core-shell nanofibers, multi-walled carbon nanotubes and gold nanoparticles that were covalently modified with the MUC1-binding aptamer. Detection is based on the change of the resistance of the electrode surface as measured by electrochemical impedance spectroscopy using hexacyanoferrate(II/III) as an electrochemical probe in working potential is 0.25 V. Scanning electron microscopy and cyclic voltammetry were also applied to characterize the electrode. The analytical response ranges from 5 to 115 nM of MUC1, with a detection limit of 2.7 nM. The assay was successfully applied to MUC1 determination in spiked serum samples where it gave satisfactory results. Graphical abstractAn impedimetric nanoprobe for the tumor marker MUC1 is proposed. It is based on use of electrospun honey core-shell nanofibers. The nanoprobe exhibits excellent sensitivity, good stability and a low detection limit.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Biomarcadores Tumorais/análise , Eletricidade , Mucina-1/análise , Nanofibras , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Sequência de Bases , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Impedância Elétrica , Eletrodos , Ferrocianetos/química , Humanos , Imunoensaio , Limite de Detecção , Mucina-1/sangue , Mucina-1/metabolismo , Nanotubos de Carbono/química
13.
Mikrochim Acta ; 186(11): 738, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676959

RESUMO

The peroxidase-like activity of hollow Prussian Blue nanocubes (hPBNCs) is used, in combination with the enzyme alcohol oxidase (AOx), in a colorimetric ethanol assay. Different from other nanozymes, the large cavity structure of the hPBNCs provides a larger surface and more binding sites for AOx to be bound on their surface or in the pores. This extremely enhances the sensitivity of the assay system. In the presence of ethanol, AOx is capable of catalyzing the oxidation of alcohols to aldehydes, accompanied by the generation of hydrogen peroxide (H2O2). The hPBNCs act as peroxidase mimics and then can catalyze the oxidation of 3,3'5,5'-tetramethylbenzidine (TMB) by H2O2, resulting in a color change of the solution from colorless to blue with a strong absorption at 652 nm. The lower detection limit for ethanol is 1.41 µg∙mL-1. Due to the high catalytic activity of hPBNCs in weakly acidic and neutral solutions, the system was successfully applied to the determination of ethanol in mice blood. This is critically important for studying the alcohol consumption and monitoring the ethanol toxicokinetics. Graphical abstract Schematic representation of hollow Prussian Blue nanocubes (hPBNCs) used as both a peroxidase mimetic and as a carrier for alcohol oxidase. Utilizing hPBNCs along with the ethanol conversion enzyme, a sensitive colorimetric assay for ethanol was developed and applied to blood samples with satisfactory results.


Assuntos
Colorimetria/métodos , Etanol/sangue , Ferrocianetos/química , Nanoestruturas/química , Oxirredutases do Álcool/química , Animais , Benzidinas/química , Materiais Biomiméticos/química , Peróxido de Hidrogênio/química , Limite de Detecção , Masculino , Camundongos Endogâmicos C57BL , Oxirredução , Peroxidase/química
14.
Nanoscale ; 11(45): 22079-22088, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31720650

RESUMO

Lanthanide-doped nanoparticles have long been stereotyped for optical luminescence bioimaging. However, they are known to be unable to produce therapeutic abilities. Here, we describe a lanthanide-based theranostic agent, namely, prussian blue (PB)-coated NaErF4@NaYF4@NaNdF4 core/shell/shell nanocrystals encapsulated in a phospholipid PEG micelle (PEG-CSS@PB), which showed switched imaging and hyperthermia abilities under distinct near infrared (NIR) light activation. The erbium (Er3+)-enriched inner core nanocrystals (NaErF4) enabled the emission of tissue-penetrating luminescence (1525 nm) in the second biological window (NIR-II, 1000-1700 nm), which endowed high-resolution optical imaging of the blood vessels and tumors under ∼980 nm excitation. High neodymium (Nd3+) concentrations in the epitaxial outer NaNdF4 shell introduced maximum cross relaxation processes that converted the absorbed NIR light (∼808 nm) into heat at high efficiencies, thus providing abilities for photothermal therapy (PTT). Importantly, the coated Prussian blue (PB) increased light absorption by about 10-fold compared to the composite free of PB, thus entailing a high light-to-heat conversion efficiency of ∼50.5%. This commensurated with that of well-established gold nanorods. As a result, the PEG-CSS@PB nanoparticles with MTT-determined low toxicities resulted in ∼80% death of HeLa cells at a dose of 600 µg mL-1 under 808 nm laser irradiance (1 W cm-2) for 10 min. Moreover, utilizing the same light dose, a single PTT treatment in tumor-bearing BALB/c mice shrunk the tumor size by ∼12-fold compared to the tumors without treatment. Our results, here, constituted a solid step forward to entitle lanthanide-based nanoparticles as theranostic agents in nanomedicine studies.


Assuntos
Materiais Revestidos Biocompatíveis , Ferrocianetos , Hipertermia Induzida , Nanopartículas , Neoplasias Experimentais , Imagem Óptica , Fototerapia , Animais , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Feminino , Ferrocianetos/química , Ferrocianetos/farmacologia , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Neodímio/química , Neodímio/farmacologia , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/terapia , Ítrio/química , Ítrio/farmacologia
15.
Molecules ; 24(22)2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31731679

RESUMO

Prussian blue (PB) is known for its multiple applications ranging from fine arts to therapeutics. More recently, PB nanoparticles have been pointed to as appealing photothermal agents (PA) when irradiated with wavelengths corresponding to the biological windows, namely regions located in the near infrared (NIR) zone. In addition, the combination of PB with other components such as phospholipids boosts their therapeutical potential by facilitating, for instance, the incorporation of drugs becoming suitable drug delivery systems. The novelty of the research relies on the synthesis procedure and characterization of hybrid lipid-PB nanoparticles with a high yield in a friendly environment suitable for photothermal therapy. This goal was achieved by first obtaining insoluble PB coated with oleylamine (OA) to facilitate its combination with lipids. The resulting lipid-PB complex showed a monomodal distribution of sizes with an overall size of around 100 nm and a polydispersity index of about 0.200. It highlights one critical step in the synthesis procedure that is the shaking time of the mixture of PB-OA nanoparticles with the lipid, which was found to be 48 h. This time assured homogeneous preparation without the need of further separation stages. Samples were stable for more than three months under several storage conditions.


Assuntos
Sistemas de Liberação de Medicamentos , Ferrocianetos/química , Lipídeos/química , Nanopartículas/química , Humanos
16.
Mikrochim Acta ; 186(12): 787, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31732807

RESUMO

An electrochemical aptasensor is described for the voltammetric determination of lipopolysaccharide (LPS) from Escherichia coli 055:B5. Aptamer chains were immobilized on the surface of a glassy carbon electrode (GCE) via reduced graphene oxide and gold nanoparticles (RGO/AuNPs). Fast Fourier transform infrared, X-ray diffraction and transmission electron microscopy were used to characterize the nanomaterials. Cyclic voltammetry, square wave voltammetry and electrochemical impedance spectroscopy were used to characterize the modified GCE. The results show that the modified electrode has a good selectivity for LPS over other biomolecules. The hexacyanoferrate redox system, typically operated at around 0.3 V (vs. Ag/AgCl) is used as an electrochemical probe. The detection limit is 30 fg·mL-1. To decrease the electrochemical potential for detection of LPS, Mg/carbon quantum dots were used as redox active media. They decrease the detection potentialto 0 V and the detection of limit (LOD) to 1 fg·mL-1. The electrode was successfully used to analyze serum of patients and healthy persons. Graphical abstractSchematic representation of the modification of reduced graphene oxide gold nanoparticles with aptamer chains to immobilize on the glassy carbon electrode surface for electrochemical detection of lipopolysaccharides.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Escherichia coli/química , Lipopolissacarídeos/sangue , Nanopartículas Metálicas/química , Sequência de Bases , Eletrodos , Ferrocianetos/química , Ouro/química , Grafite/química , Humanos , Limite de Detecção , Magnésio/química , Oxirredução , Pontos Quânticos/química
17.
Chem Commun (Camb) ; 55(98): 14844-14847, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31768507

RESUMO

Ultrasmall sub-10 nm nanoparticles of Prussian blue analogues incorporating GdIII ions at their periphery revealed longitudinal relaxivities above 40 mM-1 s-1 per GdIII regardless of the nature of the core and the polymer coating. Large T1-weighted contrast enhancements were achieved in addition to a highly efficient photothermal effect and in vivo photoacoustic imaging in tumors.


Assuntos
Ferrocianetos/química , Imagem por Ressonância Magnética/métodos , Nanopartículas/química , Nanomedicina Teranóstica , Animais , Linhagem Celular Tumoral , Meios de Contraste/química , Gadolínio/química , Humanos , Camundongos , Neoplasias/diagnóstico por imagem , Transplante Heterólogo
18.
Nat Commun ; 10(1): 4490, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31582736

RESUMO

The application of photothermal therapy to treat bacterial infections remains a challenge, as the high temperatures required for bacterial elimination can damage healthy tissues. Here, we develop an exogenous antibacterial agent consisting of zinc-doped Prussian blue (ZnPB) that kills methicillin-resistant Staphylococcus aureus in vitro and in a rat model of cutaneous wound infection. Local heat triggered by the photothermal effect accelerates the release and penetration of ions into the bacteria, resulting in alteration of intracellular metabolic pathways and bacterial killing without systemic toxicity. ZnPB treatment leads to the upregulation of genes involved in tissue remodeling, promotes collagen deposition and enhances wound repair. The efficient photothermal conversion of ZnPB allows the use of relatively few doses and low laser flux, making the platform a potential alternative to current antibiotic therapies against bacterial wound infections.


Assuntos
Antibacterianos/administração & dosagem , Terapia a Laser , Estruturas Metalorgânicas/administração & dosagem , Infecções Estafilocócicas/terapia , Infecção dos Ferimentos/terapia , Administração Cutânea , Animais , Antibacterianos/química , Terapia Combinada/métodos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ferrocianetos/administração & dosagem , Ferrocianetos/química , Humanos , Raios Infravermelhos/uso terapêutico , Masculino , Estruturas Metalorgânicas/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Células NIH 3T3 , Nanopartículas/administração & dosagem , Nanopartículas/química , Ratos , Infecções Estafilocócicas/microbiologia , Resultado do Tratamento , Cicatrização/efeitos dos fármacos , Cicatrização/efeitos da radiação , Infecção dos Ferimentos/microbiologia , Zinco/administração & dosagem , Zinco/química
19.
ACS Appl Mater Interfaces ; 11(43): 39493-39502, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31576732

RESUMO

Recently, the chemodynamic therapy (CDT) has been widely reported and applied to tumor therapy. However, only low level hydroxyl radicals (•OH) generated by the endogenous hydrogen peroxide alone are insufficient to kill the cancer cells. To overcome the insufficient therapeutic effect, this study reports a novel CDT based on Fenton catalyst Au@Prussian blue nanocubes (Au@PB NCs), subsequently encapsulated with doxorubicin (Dox). The in vitro and in vivo results indicate that the Dox-Au@PB NCs can take synergistic effects on tumor suppressor by CDT. In addition, Au@PB NCs possess high X-ray computed tomography contrast enhanced efficiency about ∼27.13 HU·mL·mg-1. This study highlights a great potential of the Dox-Au@PB NCs for tumor diagnosis and CDT.


Assuntos
Meios de Contraste , Doxorrubicina , Portadores de Fármacos , Ferrocianetos , Ouro , Nanoestruturas , Neoplasias Experimentais , Tomografia Computadorizada por Raios X , Animais , Linhagem Celular , Linhagem Celular Tumoral , Meios de Contraste/química , Meios de Contraste/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Ferrocianetos/química , Ferrocianetos/farmacologia , Ouro/química , Ouro/farmacologia , Camundongos , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/tratamento farmacológico
20.
J Mater Sci Mater Med ; 30(9): 103, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31493091

RESUMO

Metal-on-metal (MoM) hip arthroplasties produce abundant implant-derived wear debris composed mainly of cobalt (Co) and chromium (Cr). Cobalt-chromium (Co-Cr) wear particles are difficult to identify histologically and need to be distinguished from other wear particle types and endogenous components (e.g., haemosiderin, fibrin) which may be present in MoM periprosthetic tissues. In this study we sought to determine whether histological stains that have an affinity for metals are useful in identifying Co-Cr wear debris in MoM periprosthetic tissues. Histological sections of periprosthetic tissue from 30 failed MoM hip arthroplasties were stained with haematoxylin-eosin (HE), Solochrome Cyanine (SC), Solochrome Azurine (SA) and Perls' Prussian Blue (PB). Sections of periprosthetic tissue from 10 cases of non-MoM arthroplasties using other implant biomaterials, including titanium, ceramic, polymethylmethacrylate (PMMA) and ultra-high molecular weight polyethylene (UHMWP) were similarly analysed. Sections of 10 cases of haemosiderin-containing knee tenosynovial giant cell tumour (TSGCT) were also stained with HE, SC, SA and PB. In MoM periprosthetic tissues, SC stained metal debris in phagocytic macrophages and in the superficial necrotic zone which exhibited little or no trichrome staining for fibrin. In non-MoM periprosthetic tissues, UHMWP, PMMA, ceramic and titanium particles were not stained by SC. Prussian Blue, but not SC or SA, stained haemosiderin deposits in MoM periprosthetic tissues and TSGT. Our findings show that SC staining (most likely Cr-associated) is useful in distinguishing Co-Cr wear particles from other metal/non-metal wear particles types in histological preparations of periprosthetic tissue and that SC reliably distinguishes haemosiderin from Co-Cr wear debris.


Assuntos
Benzenossulfonatos , Corantes/farmacologia , Análise de Falha de Equipamento/métodos , Articulação do Quadril/patologia , Nanopartículas Metálicas/análise , Próteses Articulares Metal-Metal , Coloração e Rotulagem/métodos , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/instrumentação , Azurina/química , Azurina/farmacologia , Benzenossulfonatos/química , Benzenossulfonatos/farmacologia , Cromo/química , Corantes/síntese química , Corantes/química , Amarelo de Eosina-(YS)/química , Amarelo de Eosina-(YS)/farmacologia , Ferrocianetos/química , Ferrocianetos/farmacologia , Células Gigantes de Corpo Estranho/efeitos dos fármacos , Células Gigantes de Corpo Estranho/patologia , Hematoxilina/química , Hematoxilina/farmacologia , Articulação do Quadril/química , Articulação do Quadril/efeitos dos fármacos , Prótese de Quadril , Técnicas Histológicas/métodos , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Próteses Articulares Metal-Metal/efeitos adversos , Polietilenos/análise , Polietilenos/química
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