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1.
Int J Nanomedicine ; 16: 1889-1899, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33707944

RESUMEN

Introduction: Sonodynamic therapy (SDT) has good targeting and non-invasive advantages in the treatment of solid cancers, and checkpoint blockade immunotherapy is also a promising treatment to cure cancer. However, their antitumor effects are not sufficient due to some inherent factors. Some studies that combined SDT with immunotherapy or nanoparticles have managed to enhance its efficiency to treat cancers. Methods: In this work, an effective therapeutic strategy that can potentiate the antitumor efficacy of anti-PD-L1 antibody (aPD-L1) is developed by the use of cascade immuno-sonodynamic therapy (immuno-SDT). Titanium dioxide (TiO2), a nanostructured agent for SDT, sonosensitizer Chlorin e6 (Ce6), and immunological adjuvant CpG oligonucleotide (CpG ODN), are used to construct a multifunctional nanosonosensitizer (TiO2-Ce6-CpG). Then, we conducted in vitro and in vivo experiments to explore the antitumor effect of TiO2-Ce6-CpG under ultrasound (US) treatment. Results: The characterization tests showed that the nanosonosensitizers are polycrystalline structure with homogeneous sizes, resulting in a good drug loading efficiency. The innovative nanosonosensitizers (TiO2-Ce6-CpG) can not only effectively inhibit tumor growth but also stimulate the immune system to activate the adaptive immune responses, using the TiO2-Ce6 to augment SDT and the immune adjuvant CpG to enhance the immune response. After combined with the aPD-L1, the synergistic effect could not only efficiently inhibit the primary tumor growth but also lead to an inhibition of the non-irradiated pre-existing distant tumors by inducing a strong tumor-specific immune response. Conclusion: In this study, we present an effective strategy for tumor treatment by combining nanosonosensitizer-augmented SDT and aPD-L1 checkpoint blockade. This work provides a promising strategy and offers a new vision for treating malignant tumors.


Asunto(s)
/uso terapéutico , Inmunoterapia , Nanopartículas/química , Neoplasias/inmunología , Neoplasias/terapia , Terapia por Ultrasonido , Animales , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Terapia Combinada , Células Dendríticas/efectos de los fármacos , Endocitosis/efectos de los fármacos , Femenino , Humanos , Inmunidad/efectos de los fármacos , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Nanopartículas/ultraestructura , Neoplasias/patología , Oligodesoxirribonucleótidos/química , Porfirinas/química , Especies Reactivas de Oxígeno/metabolismo , Titanio/química
2.
Molecules ; 26(4)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670175

RESUMEN

A range of solution-processed organic and hybrid organic-inorganic solar cells, such as dye-sensitized and bulk heterojunction organic solar cells have been intensely developed recently. TiO2 is widely employed as electron transporting material in nanostructured TiO2 perovskite-sensitized solar cells and semiconductor in dye-sensitized solar cells. Understanding the optical and electronic mechanisms that govern charge separation, transport and recombination in these devices will enhance their current conversion efficiencies under illumination to sunlight. In this work, density functional theory with Perdew-Burke Ernzerhof (PBE) functional approach was used to explore the optical and electronic properties of three modeled TiO2 brookite clusters, (TiO2)n=5,8,68. The simulated optical absorption spectra for (TiO2)5 and (TiO2)8 clusters show excitation around 200-400 nm, with (TiO2)8 cluster showing higher absorbance than the corresponding (TiO2)5 cluster. The density of states and the projected density of states of the clusters were computed using Grid-base Projector Augmented Wave (GPAW) and PBE exchange correlation functional in a bid to further understand their electronic structure. The density of states spectra reveal surface valence and conduction bands separated by a band gap of 1.10, 2.31, and 1.37 eV for (TiO2)5, (TiO2)8, and (TiO2)68 clusters, respectively. Adsorption of croconate dyes onto the cluster shifted the absorption peaks to higher wavelengths.


Asunto(s)
Teoría Funcional de la Densidad , Nanoestructuras/química , Energía Solar , Titanio/química , Adsorción , Compuestos de Calcio/química , Suministros de Energía Eléctrica , Electrónica , Electrones , Óptica y Fotónica/tendencias , Óxidos/química , Luz Solar
3.
Molecules ; 26(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670660

RESUMEN

Water decontamination still remains a major challenge to some developing countries not having centralized wastewater systems. Therefore, this study presents the optimization of photocatalytic degradation of Basic Blue 41 dye in an aqueous medium by an activated carbon (AC)-TiO2 photocatalyst under UV irradiation. The mesoporous AC-TiO2 synthesized by a sonication method was characterized by X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectroscopy for crystal phase identification and molecular bond structures, respectively. The efficiency of the AC-TiO2 was evaluated as a function of three input variables viz. catalyst load (2-4 g), reaction time (15-45 min) and pH (6-9) by using Box-Behnken design (BBD) adapted from response surface methodology. Using color and turbidity removal as responses, a 17 run experiment matrix was generated by the BBD to investigate the interaction effects of the three aforementioned input factors. From the results, a reduced quadratic model was generated, which showed good predictability of results agreeable to the experimental data. The analysis of variance (ANOVA), signposted the selected models for color and turbidity, was highly significant (p < 0.05) with coefficients of determination (R2) values of 0.972 and 0.988, respectively. The catalyst load was found as the most significant factor with a high antagonistic impact on the process, whereas the interactive effect of reaction time and pH affected the process positively. At optimal conditions of catalyst load (2.6 g), reaction time (45 min), and pH (6); the desirability of 96% was obtained by a numerical optimization approach representing turbidity removal of 93% and color of 96%.


Asunto(s)
Compuestos Azo/efectos de la radiación , Benzotiazoles/efectos de la radiación , Carbón Orgánico/química , Fotólisis/efectos de la radiación , Titanio/química , Rayos Ultravioleta , Análisis de Varianza , Catálisis/efectos de la radiación , Color , Concentración de Iones de Hidrógeno , Cinética , Nefelometría y Turbidimetría , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
4.
J Chromatogr A ; 1641: 461981, 2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33684778

RESUMEN

Asymmetrical flow field-flow fractionation (AF4) hyphenated with inductively coupled plasma-mass spectrometry (ICP-MS) has been widely used to characterize metal containing particles. This study demonstrates the advantages of coupling AF4 with ICP-time-of-flight mass spectrometry (ICP-TOFMS) in standard and single particle modes to determine size distribution, elemental composition, and number concentration of composite particles. The coupled system was used to characterize two complex particle mixtures. The first mixture consisted of particles extracted from micro-alloyed steels with two size populations of different elemental composition. The second mixture consisted of particles extracted from soil spiked with various engineered nanoparticles (ENPs). The equivalent hydrodynamic sizes of individual micro-alloyed steel particles were up to 6 times larger than the sizes determined by single particle (sp)-ICP-TOFMS. The larger AF4 sizes were attributed to the presence of a surface coating, which is not reflected in the core size determined by sp-ICP-TOFMS. Two particle populations could not be separated by AF4 due to their broad size distributions but were resolved by sp-ICP-TOFMS using their unique elemental signatures. Multi-angle light scattering and ICP-TOFMS signals of soil suspensions increased with the spiked ENP concentrations. However, only after conducting full element screening and single particle fingerprinting by ICP-TOFMS could this increase be attributed to enhanced extraction efficiency of natural particles and the risk for false conclusions be eliminated. In this study, we describe how AF4 coupled to ICP-TOFMS can be applied to study complex samples of inorganic particles which contain organic compounds.


Asunto(s)
Fraccionamiento de Campo-Flujo/métodos , Espectrometría de Masas/métodos , Nanopartículas/química , Nitrilos/química , Tamaño de la Partícula , Dispersión de Radiación , Procesamiento de Señales Asistido por Computador , Suelo/química , Análisis Espectral , Titanio/química
5.
J Chromatogr A ; 1640: 461942, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33588274

RESUMEN

Recent years have seen the field of extracellular vesicle (EV) studies burgeoning. This is mainly because EV constituents including nucleic acid, proteins, lipids, and metabolites are promising sources towards disease biomarker discovery. However, EV study remains challenging due to the complexity of biofluids as well as technical limitations during sample preparation. Here, we proposed a simple method combing ultrafiltration (UF) and phospholipid affinity to collect high purity EVs from 30 mL of urine sample for their metabolomic profiling. Ultracentrifugation (UC) for EV isolation was applied as a reference method. Western blot (WB) analysis, nanoparticles tracking analysis (NTA) and electron microscopy (EM) were used to assess EV protein markers and to characterize vesicle size and morphology. The results revealed that more than 1010 EV particles could be isolated from a 30 mL urine sample by the proposed method, and the resulting EVs carry specific protein markers and had a typical "cup shape" morphology. This suggests that our method is suitable for EV isolation and can provide sufficient EV quantity to ensure downstream analysis. Further untargeted metabolomic profiling of isolated EVs by UHPLC-QTOF-MS detected 433 metabolites by our methods and 432 metabolites by UC with a MS/MS similarity score greater than 0.7. We then applied the lipid metabolites-targeted method using UHPLC-QTrap-MS with the MRM mode, which successfully detected 467 compounds from urine EVs. This indicates that UF integrating phospholipid affinity is a reliable method for metabolic analysis of urinary EVs, which holds the potential for EV clinical application towards biomarker investigation from their metabolites.


Asunto(s)
Vesículas Extracelulares/metabolismo , Metabolómica/métodos , Fosfolípidos/aislamiento & purificación , Fosfolípidos/metabolismo , Ultrafiltración/métodos , Orina/química , Vesículas Extracelulares/ultraestructura , Humanos , Metaboloma , Espectrometría de Masas en Tándem , Titanio/química
6.
ACS Appl Mater Interfaces ; 13(7): 7897-7912, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33570904

RESUMEN

Titanium dioxide (TiO2) nanostructures including nanopores and nanotubes have been fabricated on titanium (Ti)-based orthopedic/dental implants via electrochemical anodization (EA) to enable local drug release and enhanced bioactivity. EA using organic electrolytes such as ethylene glycol often requires aging (repeated anodization of nontarget Ti) to fabricate stable well-ordered nanotopographies. However, limited information is available with respect to its influence on topography, chemistry, mechanical stability, and bioactivity of the fabricated structures. In the current study, titania nanopores (TNPs) using a similar voltage/time were fabricated using different ages of electrolyte (fresh/0 h to 30 h aged). Current density vs time plots of EA, changes in the electrolyte (pH, conductivity, and Ti/F ion concentration), and topographical, chemical, and mechanical characteristics of the fabricated TNPs were compared. EA using 10-20 h electrolytes resulted in stable TNPs with uniform size and improved alignment (parallel to the underlying substrate microroughness). Additionally, to evaluate bioactivity, primary human gingival fibroblasts (hGFs) were cultured onto various TNPs in vitro. The findings confirmed that the proliferation and morphology of hGFs were enhanced on 10-20 h aged electrolyte anodized TNPs. This pioneering study systematically investigates the optimization of anodization electrolyte toward fabricating nanoporous implants with desirable characteristics.


Asunto(s)
Nanoporos , Titanio/química , Técnicas Electroquímicas , Electrólitos/química , Flúor/química , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Propiedades de Superficie , Factores de Tiempo
7.
Nat Commun ; 12(1): 1224, 2021 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-33619276

RESUMEN

In view of increasing drug resistance, ecofriendly photoelectrical materials are promising alternatives to antibiotics. Here we design an interfacial Schottky junction of Bi2S3/Ti3C2Tx resulting from the contact potential difference between Ti3C2Tx and Bi2S3. The different work functions induce the formation of a local electrophilic/nucleophilic region. The self-driven charge transfer across the interface increases the local electron density on Ti3C2Tx. The formed Schottky barrier inhibits the backflow of electrons and boosts the charge transfer and separation. The photocatalytic activity of Bi2S3/Ti3C2Tx intensively improved the amount of reactive oxygen species under 808 nm near-infrared radiation. They kill 99.86% of Staphylococcus aureus and 99.92% of Escherichia coli with the assistance of hyperthermia within 10 min. We propose the theory of interfacial engineering based on work function and accordingly design the ecofriendly photoresponsive Schottky junction using two kinds of components with different work functions to effectively eradicate bacterial infection.


Asunto(s)
Bismuto/química , Luz , Viabilidad Microbiana/efectos de la radiación , Sulfuros/química , Titanio/química , Animales , Antibacterianos/farmacología , Catálisis/efectos de la radiación , Teoría Funcional de la Densidad , Colorantes Fluorescentes/química , Masculino , Ratones , Viabilidad Microbiana/efectos de los fármacos , Células 3T3 NIH , Nanopartículas/química , Ratas Wistar , Especies Reactivas de Oxígeno/química , Análisis Espectral , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/efectos de la radiación , Electricidad Estática , Temperatura
8.
Int J Nanomedicine ; 16: 667-682, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33531806

RESUMEN

Background: Nanostructured surface modifications of Ti-based biomaterials are moving up from a highly-promising to a successfully-implemented approach to developing safe and reliable implants. Methods: The study's main objective is to help consolidate the knowledge and identify the more suitable experimental strategies related to TiO2 nanotubes-modified surfaces. In this sense, it proposes the thorough investigation of two optimized nanotubes morphologies in terms of their biological activity (cell cytotoxicity, alkaline phosphatase activity, alizarin red mineralization test, and cellular adhesion) and their electrochemical behavior in simulated body fluid (SBF) electrolyte. Layers of small-short and large-long nanotubes were prepared and investigated in their amorphous and crystallized states and compared to non-anodized samples. Results: Results show that much more than the surface area development associated with the nanotubes' growth; it is the heat treatment-induced change from amorphous to crystalline anatase-rutile structures that ensure enhanced biological activity coupled to high corrosion resistance. Conclusion: Compared to both non-anodized and amorphous nanotubes layers, the crystallized nano-structures' outstanding bioactivity was related to the remarkable increase in their hydrophilic behavior, while the enhanced electrochemical stability was ascribed to the thickening of the dense rutile barrier layer at the Ti surface beneath the nanotubes.


Asunto(s)
Nanotubos/química , Prótesis e Implantes , Titanio/química , Fosfatasa Alcalina/metabolismo , Adhesión Celular , Línea Celular Tumoral , Supervivencia Celular , Corrosión , Electroquímica , Electrólitos/química , Humanos , Nanotubos/ultraestructura , Humectabilidad
9.
J Chromatogr A ; 1639: 461938, 2021 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-33535116

RESUMEN

A sorbent for the extraction of organophosphorus flame retardants has been proposed, based on UVM-7 (University of Valencia Materials) mesoporous silica doped with titanium. Designed cartridges have been applied to the extraction and preconcentration of flame retardants in water samples, followed by gas chromatography coupled to a mass spectrometry detector. Firstly, UVM-7 materials with different contents of titanium were synthesized and characterized by several techniques, thus confirming the proper mesoporous architecture. The potential of these materials was assessed in comparison with their morphological properties, resulting Ti50-UVM-7 the best solid phase. Several extraction parameters were also optimized. Analytical parameters were also evaluated, and limits of detection from 0.019 to 0.21 ng mL-1 were obtained, as well as intra-day relative standard deviation below 11% for all analytes. Extraction efficiencies above 80% in water samples were achieved. The reusability of the material was also proved. Finally, the designed protocol was applied for the analysis of real water samples, and quantifiable concentrations of tris(2-chloroisopropyl) phosphate (TCIPP), tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPhP) were obtained in some samples. The method was compared with a United States Environmental Protection Agency general method with C18 cartridges.


Asunto(s)
Retardadores de Llama/análisis , Compuestos Organofosforados/análisis , Dióxido de Silicio/química , Titanio/química , Agua/química , Adsorción , Límite de Detección , Organofosfatos/análisis , Porosidad , Microextracción en Fase Sólida
10.
J Vis Exp ; (168)2021 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-33616110

RESUMEN

Organic-inorganic perovskites have an impressive potential for the design of next generation solar cells and are currently considered for upscaling and commercialization. Currently, perovskite solar cells rely on spin-coating which is neither practical for large areas nor environmentally friendly. Indeed, one of the conventional and most effective lab-scale methods to induce perovskite crystallization, the antisolvent method, requires an amount of toxic solvent that is difficult to apply on larger surfaces. To solve this problem, an antisolvent-free and rapid thermal annealing process called flash infrared annealing (FIRA) can be used to produce highly crystalline perovskite films. The FIRA oven is composed of an array of near-infrared halogen lamps with an illumination power of 3,000 kW/m2. A hollow aluminum body enables an effective water-cooling system. The FIRA method allows the synthesis of perovskite films in less than 2 s, achieving efficiencies >20%. FIRA has a unique potential for the industry because it can be adapted to continuous processing, is antisolvent-free, and does not require lengthy, hour-long annealing steps.


Asunto(s)
Compuestos de Calcio/química , Rayos Infrarrojos , Óxidos/química , Energía Solar , Solventes/química , Titanio/química , Cristalización
11.
Molecules ; 26(3)2021 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-33572957

RESUMEN

Lead halide perovskites are currently widely investigated as active materials in photonic and optoelectronic devices. While the lack of long term stability actually limits their application to commercial devices, several experiments demonstrated that beyond the irreversible variation of the material properties due to degradation, several possibilities exist to reversibly modulate the perovskite characteristics by acting on the environmental conditions. These results clear the way to possible applications of lead halide perovskites to resistive and optical sensors. In this review we will describe the current state of the art of the comprehension of the environmental effects on the optical and electronic properties of lead halide perovskites, and of the exploitation of these results for the development of perovskite-based sensors.


Asunto(s)
Técnicas Biosensibles , Compuestos de Calcio/química , Plomo/química , Óptica y Fotónica/métodos , Óxidos/química , Titanio/química , Clima , Electrónica , Monitoreo del Ambiente , Humanos , Compuestos Inorgánicos/química , Compuestos Inorgánicos/aislamiento & purificación , Plomo/aislamiento & purificación
12.
Methods Mol Biol ; 2261: 55-72, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33420984

RESUMEN

Posttranslational modifications (PTMs) such as phosphorylation, acetylation, and glycosylation are an essential regulatory mechanism of protein function and interaction, and they are associated with a wide range of biological processes. Since most PTMs alter the molecular mass of a protein, mass spectrometry (MS) is the ideal analytical tool for studying various PTMs. However, PTMs are often present in substoichiometric levels, and therefore their unmodified counterpart often suppresses their signal in MS. Consequently, PTM analysis by MS is a challenging task, requiring highly specialized and sensitive PTM-specific enrichment methods. Currently, several methods have been implemented for PTM enrichment, and each of them has its drawbacks and advantages as they differ in selectivity and specificity toward specific protein modifications. Unfortunately, for the vast majority of more than 400 known modifications, we have no or poor tools for selective enrichment.Here, we describe a comprehensive workflow to simultaneously study phosphorylation, acetylation, and N-linked sialylated glycosylation from the same biological sample. The protocol involves an initial titanium dioxide (TiO2) step to enrich for phosphopeptides and sialylated N-linked glycopeptides followed by glycan release and post-fractionation using sequential elution from immobilized metal affinity chromatography (SIMAC) to separate mono-phosphorylated and deglycosylated peptides from multi-phosphorylated ones. The IMAC flow-through and acidic elution are subsequently subjected to a next round of TiO2 enrichment for further separation of mono-phosphopeptides from deglycosylated peptides. Furthermore, the lysine-acetylated peptides present in the first TiO2 flow-through fraction are enriched by immunoprecipitation (IP) after peptide cleanup. Finally, the samples are fractionated by high pH reversed phase chromatography (HpH) or hydrophilic interaction liquid chromatography (HILIC ) to reduce sample complexity and increase the coverage in the subsequent LC-MS /MS analysis. This allows the analysis of multiple types of modifications from the same highly complex biological sample without decreasing the quality of each individual PTM study.


Asunto(s)
Procesamiento Proteico-Postraduccional , Proteínas/análisis , Proteómica , Acetilación , Cromatografía de Afinidad , Cromatografía de Fase Inversa , Glicosilación , Inmunoprecipitación , Fosforilación , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem , Titanio/química , Flujo de Trabajo
13.
Ecotoxicol Environ Saf ; 210: 111866, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33387906

RESUMEN

A novel composite electrospun fiber with high photocatalytic efficiency, good stability, strong hydrophobicity, good pollution resistance, and easy separation and recovery was synthesized. The TiO2@g-C3N4 (TCN) with special core-shell structure (5-10 nm shell) facilitated the separation of photogenerated electron-holes and had high photocatalytic performance. The poly (vinylidene fluoride) (PVDF) electrospun fiber immobilized with TCN was successfully fabricated (PVDF-TCN) with uniform distribution and size of nanofibers by using electrospinning, which was used for degrading tetracycline under visible-light irradiation (> 400 nm). A special rougher surface of electrospun fiber obtained by washing of sacrificial PVP increased the specific surface area, which became more conducive to the adhesion of the catalyst. The water contact angle and FTIR results demonstrated that the electrospun fiber became extremely hydrophilic after adding TCN catalyst, which could effectively mitigate the fiber pollution. The PVDF-TCN-0.2g electrospun fiber exhibited excellent photocatalytic performance and the degradation efficiency of tetracycline was up to 97% in 300 min under visible-light irradiation. The mechanism of PVDF-TCN electrospun fiber degradation of tetracycline in the photocatalytic process was also proposed. In addition, the PVDF-TCN-0.2g exhibited a stable activity after 4 cycles experiments since the degradation efficiency remained about 90%. Therefore, we believed this study provided a new strategy in catalyst immobilization and wastewater treatment.


Asunto(s)
Antibacterianos/química , Nanofibras/efectos de la radiación , Nitrilos/efectos de la radiación , Polivinilos/efectos de la radiación , Tetraciclina/química , Titanio/efectos de la radiación , Contaminantes Químicos del Agua/química , Catálisis , Luz , Nanofibras/química , Nitrilos/química , Procesos Fotoquímicos , Polivinilos/química , Titanio/química , Purificación del Agua/métodos
14.
Ecotoxicol Environ Saf ; 210: 111862, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33429321

RESUMEN

Microcystin-leucine arginine (MC-LR) is a carcinogenic toxin, produced by cyanobacteria. The release of this toxin into drinking water sources can threaten public health and environmental safety. Therefore, effective MC-LR removal from water resources is necessary. In the present study, the hydrothermal method was used to synthesize a novel ternary BiVO4/TiO2/NaY-Zeolite (B/T/N-Z) nanocomposite for MC-LR degradation under visible light. FESEM, FTIR, XRD, and DRS were performed for characterizing the nanocomposite structure. Also, the Response Surface Methodology (RSM) was applied to determine the impact of catalyst dosage, pH, and contact time on the MC-LR removal. High-performance liquid chromatography was performed to measure the MC-LR concentration. Based on the results, independent parameters, including contact time, catalyst dosage, and pH, significantly affected the MC-LR removal (P < 0.05). In other words, increasing the contact time, catalyst dosage, and acidic pH had positive effects on MC-LR removal. Among these variables, the catalyst dosage, with the mean square and F-value of 1041.37 and 162.84, respectively, had the greatest effect on the MC-LR removal efficiency. Apart from the interaction between the catalyst dosage and contact time, the interaction effects of other parameters were not significant. Also, the maximum MC-LR removal efficiency was 99.88% under optimal conditions (contact time = 120 min, catalyst dosage = 1 g/L, and pH = 5). According to the results, the B/T/N-Z nanocomposite, as a novel and effective photocatalyst could be used to degrade MC-LR from polluted water.


Asunto(s)
Luz , Toxinas Marinas/química , Microcistinas/química , Nanocompuestos/efectos de la radiación , Titanio/efectos de la radiación , Vanadatos/efectos de la radiación , Contaminantes Químicos del Agua/química , Itrio/efectos de la radiación , Zeolitas/efectos de la radiación , Bismuto/química , Catálisis , Nanocompuestos/química , Procesos Fotoquímicos , Titanio/química , Vanadatos/química , Purificación del Agua/métodos , Itrio/química , Zeolitas/química
15.
Anal Chem ; 93(4): 2090-2096, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33435685

RESUMEN

The sensitive detection of coronavirus is of vital importance for the prevention of its rapid spread. Porcine epidemic diarrhea virus (PEDV) is a highly contagious coronavirus that causes severe diarrhea and death in neonatal piglets. In this work, a novel PCN-224-based electrochemiluminescence (ECL) system was constructed for PEDV detection with high sensitivity. We found that PCN-224 can be employed as an ECL reporter with a strong signal because of its zirconium-based organic porous frame nanomaterial with a large specific surface area and stable structure. TiO2 nanoparticles were used as an accelerator for the first time to promote the reduction of coreactant potassium peroxydisulfate on the cathode; thus, the initial ECL signal of PCN-224 was significantly amplified. In the presence of PEDV, the ECL signal decreased due to the block effect to electron transfer. As a result, the novel "signal off" biosensor achieved a sensitive detection of PEDV ranging from 1 pg/mL to 10 ng/mL, with a detection limit of 0.4 pg/mL (S/N = 3). Importantly, the PCN-224 nanomaterial enriched the ECL system in biological analysis, and the proposed strategy provided a new route for coronavirus detection.


Asunto(s)
Técnicas Electroquímicas/métodos , Estructuras Metalorgánicas/química , Porfirinas/química , Circonio/química , Técnicas Biosensibles , Luminiscencia , Nanopartículas del Metal/química , Microscopía Electrónica de Transmisión , Titanio/química
16.
Ecotoxicol Environ Saf ; 208: 111677, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396009

RESUMEN

CH3NH3PbI3 is one of the most widely studied and most promising photoelectric conversion materials for large-scale application. However, once it is discharged into the aquatic environment, it will release a variety of lethal substances to the aquatic organisms. Herein, two typical aquatic pollution indicators, Scenedesmus obliquus (a typical phytoplankton) and Daphnia magna (a typical zooplankton), were used to assess the acute effects of CH3NH3PbI3 perovskite on aquatic organisms. The results showed that, when the initial CH3NH3PbI3 perovskite level (CPL) was 40 mg L-1 or higher, the growth of S. obliquus would be remarkably inhibited with significant decreases of chlorophyll content and protein content. And when the CPL was over 5 mg L-1, the survival of D. magna would be notably threatened. Specifically, the 72 h EC-50 of CH3NH3PbI3 perovskite to S. obliquus was calculated as 37.21 mg L-1, and the 24 h LC-50 of this perovskite to D. magna adults and neonates were calculated as 37.53 mg L-1 and 18.55 mg L-1, respectively. Moreover, remarkably solution pH declination and large amounts of lead bio-accumulation was observed in the both acute experiments, which could be the main reasons causing the above acute effects. Considering the strong acute effects of these CH3NH3PbI3 perovskite materials and their attractive application prospect, more attentions should be paid on their harmness to the environment.


Asunto(s)
Compuestos de Calcio/toxicidad , Daphnia/efectos de los fármacos , Plomo/toxicidad , Metilaminas/toxicidad , Óxidos/toxicidad , Scenedesmus/efectos de los fármacos , Titanio/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Organismos Acuáticos/efectos de los fármacos , Compuestos de Calcio/química , Humanos , Plomo/química , Metilaminas/química , Óxidos/química , Propiedades de Superficie , Titanio/química , Pruebas de Toxicidad Aguda , Contaminantes Químicos del Agua/química
17.
Ecotoxicol Environ Saf ; 208: 111634, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33396154

RESUMEN

The Quantitative Structure-Activity Relationship (QSAR) has been used to investigate organic mixtures but QSAR in the nanomaterial field (QNAR) is still new. Toxicity is a result of the interaction of many substances. QNAR research focuses on a single nanomaterial in the long-term. It is difficult to find an appropriate descriptor to build a model due to the complexity of the mixture. Here, we attempt to build a QNAR model to predict cell viability for HK-2 cells exposed to a mixture containing nano-TiO2 and heavy metals. HK-2 cells were exposed to four groups of mixtures containing heavy-metals and nanomaterials and CCK8 was added to obtain the number of living cells. At the same time, ROS was investigated to study this mechanism. Each descriptor of the components and mixtures were obtained using the formula Dmix= [Formula: see text] respectively. We used the Multiple Partial Least Squares Regression (PLS) and Random Forest Regression (RF) to build a QNAR model. Both models reliably predict and assess viability of HK-2 cells exposed to the mixture. The RF model showed greater stability and higher precision in toxicity predictability and can be applied to environmental nano-toxicology.


Asunto(s)
Ecotoxicología/métodos , Metales Pesados/toxicidad , Nanoestructuras/toxicidad , Relación Estructura-Actividad Cuantitativa , Titanio/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Metales Pesados/química , Nanoestructuras/química , Especies Reactivas de Oxígeno/metabolismo , Titanio/química
18.
ACS Appl Mater Interfaces ; 13(2): 3011-3023, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33411493

RESUMEN

Recent advancements in two-dimensional materials have brought MXene (Ti3C2) into attention due to its exciting properties as a very promising material for various applications. In this work, we report a novel Ti3C2 nanobipyramid (Ti3C2 NB) structure obtained through a three-step process involving exfoliation, delamination, and subsequent hydrothermal treatment. The morphological and textural properties at each step of synthesis were studied using an array of experimental techniques such as transmission electron microscopy, scanning electron microscopy, and atomic force microscopy and the chemical properties through X-ray diffraction, Raman, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy analysis. The Ti3C2 NBs exhibit fluorescence with an excitation-dependent emission. Further, the effect of temperature and pH on the fluorescence was also investigated, which opens up its scope in bioanalytical applications. Ti3C2 NBs showed a ∼43% increase in photoluminescence intensity from pH 3 to 11 while a ∼38% increase with the temperature from 20 to 80 °C. Usually, MXenes are highly susceptible to oxidation, but the Ti3C2 NBs were found to be chemically and optically stable even after 30 days. Bestowed with good hydrophilicity, the material exhibited high biocompatibility on the mouse fibroblast cell line L929. Further, L929 cells also showed good cellular adhesion on a Ti3C2 NB-modified glass substrate. These properties pave a way for its multifunctional ability as a sensor for pH and temperature as well as bioimaging.


Asunto(s)
Nanoestructuras/química , Titanio/química , Animales , Técnicas Biosensibles/métodos , Línea Celular , Concentración de Iones de Hidrógeno , Ratones , Nanoestructuras/ultraestructura , Nanotecnología , Temperatura
19.
ACS Appl Mater Interfaces ; 13(2): 2245-2255, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33416320

RESUMEN

Self-disinfecting textile materials employing combined photodynamic/photothermal effects enable the prevention of microbial infections, a property that has great potential in healthcare applications. However, smart textiles with stimulus responses to ambient temperature are marvelous materials for enhancing their photothermal applications with additional functions. It is still challenging to realize vivid and contrasting color changes as temperature indicators. Herein, through the in situ growth of PCN-224 metal-organic frameworks (MOFs), the electrospraying of a Ti3C2 MXene colloid, and the screen printing of a thermochromic dye, a smart photothermochromic self-disinfecting textile has been fabricated. An antibacterial inactivation study revealed 99.9999% inactivation toward gram-negative (Escherichia coli ATCC 8099) and gram-positive (Staphylococcus aureus ATCC 6538) bacteria in 30 min. A mechanism study revealed that light-driven singlet oxygen and heat are the main reasons for bacterial inactivation. Interestingly, the fabrics presented photothermal effects not only under a handheld 780 nm NIR laser but also under visible Xe lamp (λ ≥ 420 nm) illumination. The color of the fabrics (S-CF@PCN0.08) changed completely from dark green to dark red when the temperature exceeded 45 °C under Xe lamp illumination. Furthermore, the photothermochromic effect occurred in just 1 s under a 780 nm laser. Taken together, this smart photothermochromic self-disinfecting textile permits a new way to feedback the timely signal of temperature by color change and provides novel insights into the development of self-disinfecting textiles.


Asunto(s)
Antibacterianos/química , Colorantes/química , Desinfección/métodos , Estructuras Metalorgánicas/química , Textiles/microbiología , Titanio/química , Antibacterianos/farmacología , Infecciones Bacterianas/prevención & control , Colorantes/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/efectos de la radiación , Calor , Humanos , Luz , Estructuras Metalorgánicas/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/efectos de la radiación , Temperatura , Titanio/farmacología
20.
ACS Appl Mater Interfaces ; 13(3): 3653-3668, 2021 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-33439005

RESUMEN

A thin layer of gold nanoparticles (Au NPs) sputtered on cadmium sulfide quantum dots (CdS QDs) decorated anodic titanium dioxide nanotubes (TNTs) (Au/CdS QDs/TNTs) was fabricated and explored for the nonenzymatic detection of cholesterol and hydrogen peroxide (H2O2). Morphological studies of the sensor revealed the formation of uniform nanotubes decorated with a homogeneously dispersed CdS QDs and Au NPs layer. The electrochemical measurements showed an enhanced electrocatalytic performance with a fast electron transfer (∼2 s) between the redox centers of each analyte and electrode surface. The hybrid nanostructure (Au/CdS QDs/TNTs) electrode exhibited about a 6-fold increase in sensitivity for both cholesterol (10,790 µA mM-1 cm-2) and H2O2 (78,833 µA mM-1 cm-2) in analyses compared to the pristine samples. The hybrid electrode utilized different operational potentials for both analytes, which may lead to a voltage-switchable dual-analyte biosensor with a higher selectivity. The biosensor also demonstrated a good reproducibility, thermal stability, and increased shelf life. In addition, the clinical significance of the biosensor was tested for cholesterol and H2O2 in real blood samples, which showed maximum relative standard deviations of 1.8 and 2.3%, respectively. These results indicate that a Au/CdS QDs/TNTs-based hybrid nanostructure is a promising choice for an enzyme-free biosensor due to its suitable band gap alignment and higher electrocatalytic activities.


Asunto(s)
Técnicas Biosensibles/métodos , Colesterol/sangre , Oro/química , Peróxido de Hidrógeno/sangre , Nanopartículas del Metal/química , Compuestos de Cadmio/química , Técnicas Electroquímicas/métodos , Humanos , Límite de Detección , Nanotubos/química , Puntos Cuánticos/química , Sulfuros/química , Titanio/química
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