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1.
Chem Commun (Camb) ; 60(52): 6687-6690, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38863302

RESUMEN

Herein, a scheme of Sr2+/Ca2+ ion substitution was employed to simultaneously regulate the defect and intervalence charge transfer (IVCT) state of Sr2-xCaxNb2O7:Pr3+ phosphors, resulting in a dual-modulation strategy for enhancing phosphor thermal stability.

2.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(6): 605-610, 2024 Jun 15.
Artículo en Chino | MEDLINE | ID: mdl-38926377

RESUMEN

OBJECTIVES: To investigate the expression of microRNA-142 (miR-142) in children with autoimmune thyroid disease (AITD) and its relationship with the imbalance of helper T cell 17 (Th17) and regulatory T cell (Treg). METHODS: A total of 89 children hospitalized for AITD from January 2019 to December 2022 were prospectively selected as the study subjects, including 48 children with Graves' disease (GD group) and 41 children with Hashimoto's thyroiditis (HT group). Additionally, 55 healthy children undergoing physical examinations during the same period were selected as the control group. The differences in serum miR-142, antithyroglobulin antibody (TGAb), antithyroperoxidase antibody (TPOAb), Th17/Treg, and interleukin-17 (IL-17) expression were compared among the groups. RESULTS: The expression of miR-142, TPOAb, TGAb, Th17, Th17/Treg, and IL-17 in the GD group and HT group was higher than that in the control group, while Treg was lower than that in the control group (P<0.05). Pearson correlation analysis revealed that in the GD group, miR-142 was positively correlated with TPOAb, TGAb, Th17, Th17/Treg, and IL-17 (r=0.711, 0.728, 0.785, 0.716, 0.709, respectively; P<0.001) and negatively correlated with Treg (r=-0.725, P<0.001); in the HT group, miR-142 was positively correlated with TPOAb and TGAb (r=0.752, 0.717, respectively; P<0.001). CONCLUSIONS: miR-142 is highly expressed in children with AITD, and its expression may be related to the Th17/Treg imbalance in children with GD.


Asunto(s)
Interleucina-17 , MicroARNs , Linfocitos T Reguladores , Células Th17 , Humanos , MicroARNs/sangre , Células Th17/inmunología , Niño , Masculino , Femenino , Linfocitos T Reguladores/inmunología , Interleucina-17/sangre , Enfermedad de Hashimoto/inmunología , Enfermedad de Hashimoto/genética , Enfermedad de Hashimoto/sangre , Preescolar , Enfermedad de Graves/inmunología , Enfermedad de Graves/genética , Adolescente , Autoanticuerpos/sangre
3.
Dalton Trans ; 53(9): 4132-4138, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38317626

RESUMEN

Praseodymium (Pr3+) ion and the transition metal vanadium (V5+) ion with d0 electronic configuration can form an intervalence charge transfer (IVCT) band, which can function both as a compensatory channel for its red emission and as a quenching channel, thus affecting the luminescence thermal stability of the phosphors. Research studies reveal that the emission of Pr3+ in the YVO4 matrix can be quenched by the IVCT mechanism, thereby limiting the application of phosphors. As such, the present contribution is based on the solid solution replacement strategy to inhibit the constitutent of the IVCT quenching channel and thus improve thermal stability. Therefore, phosphonium (P5+) with a valence state matching V5+ and a similar ion radius was selected for the V/P substitution. It lacks a d0 electron configuration, preventing the formation of an IVCT band with Pr3+ and thereby inhibiting the construction of the quenching channels to enhance thermal stability. While the empirical formula of IVCT indicates a decrease in the IVCT energy level from 3.32438 to 3.06251 eV upon the introduction of P5+, the PLE spectra demonstrate a sharp reduction in IVCT intensity, i.e., weakening of the quenching channel. The thermal stability of the phosphors at different excitation locations was enhanced with the rise of P5+ concentration. When excited at the 3P2 level, the Y0.995PO4:0.5%Pr3+ phosphor demonstrated highly stable red emission from 303 to 523 K, with a luminescence integrated intensity ranging from 95.5% to 105.3% compared to that at 303 K. This research provides a novel approach for inhibiting the IVCT quenching channel and broadens the commercial value of YVO4:Pr3+ phosphor for various applications.

4.
Anal Chem ; 96(8): 3645-3654, 2024 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-38356334

RESUMEN

Accurate measurement of cancer markers in urine is a convenient method for tumor monitoring. However, the concentration of cancer markers in urine is so low that it is difficult to achieve their measurement. Photoelectrochemical (PEC) sensors are a promising technology to realize the detection of trace cancer markers due to their high sensitivity. Currently, the interference of nonspecific biomolecules in urine is the main reason affecting the high sensitivity and selectivity of PEC sensors in detecting cancer markers. In this work, a strategy of oxygen vacancy (OV) modulation is proposed to construct a fouling-resistant PEC aptamer sensing platform for the detection of α-fetoprotein (AFP), a liver cancer marker. The introduction of OVs induces the formation of intermediate localized states in the photoelectric material, which not only facilitates the separation of photogenerated carriers but also leads to the redshift of the light absorption edge. More importantly, OVs with positive electrical properties can be employed to modify the antifouling layer (C-PEG) with negatively charged groups through an electrostatic interaction. The synergistic effect of OVs, antifouling layer, and aptamer resulted in a TiO2/OVs/C-PEG-based PEC sensor achieves a wide linear range from 1 pg/mL to 100 ng/mL and a low detection limit of 0.3 pg/mL for AFP. In addition, the sensor successfully realized the determination of AFP in urine samples and accurately differentiated between normal people and liver cancer patients in the early and advanced stages. This project is of great significance in advancing the application of photoelectrochemical bioanalytical technology to achieve the detection of cancer markers in urine by investigating the construction of an OVs-regulated fouling-resistant sensing interface.


Asunto(s)
Incrustaciones Biológicas , Técnicas Biosensibles , Neoplasias Hepáticas , Humanos , alfa-Fetoproteínas , Oxígeno , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Límite de Detección
5.
Chem Commun (Camb) ; 60(20): 2804-2807, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38362808

RESUMEN

In our work, a totally anomalous thermal quenching phenomenon of red-shifted and enhanced charge transfer state (CTS) absorption is found for the first time in LiTaO3:xPr3+ phosphors. The crystal structure, luminescent properties and the mechanism of abnormal thermal quenching were investigated in detail.

6.
Chem Rec ; 23(3): e202200259, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36744591

RESUMEN

Water splitting is considered as a promising technology to solve energy shortage and environmental pollution. Since oxygen evolution reaction (OER) directly affects the efficiency of hydrogen evolution, the preparation of efficient and inexpensive OER catalysts is an urgent problem. "Low-temperature immersion" (LTI) is expected to be a prospective strategy for electrocatalyst preparation due to its simplicity and energy-saving advantages. However, there is almost no comprehensive overview on the progress of LTI engineering in the construction of non-precious metal self-supported electrocatalysts for OER. Herein, this review firstly introduces the principles and applications of LTI engineering-assisted preparation of non-precious metal self-supported electrocatalysts in terms of etching and deposition. Then the mechanism of OER is analyzed from an amorphous viewpoint, and finally some perspective insights and future challenges of this method are discussed.

7.
Dalton Trans ; 50(36): 12592-12606, 2021 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-34545889

RESUMEN

The synthesis conditions of most phosphors doped with lanthanide ions with d-f transition require a reducing atmosphere. The doping Bi3+ ions selected in this study perfectly avoid this requirement, and they are environmentally friendly and safe. Nevertheless, the spectral tuning of Bi3+ is a great challenge that limits its application. Herein, by regulating the value of x in the new solid solution Sr2+xLa1-xGaO5-xFx, the luminescence of Bi3+ is well promoted. Through an excitation-driven strategy, the emission peak position of Bi3+ is redshifted, and the luminescence of trivalent bismuth is successfully adjusted, which can also be applied to anti-blue lighting. In addition, we constructed a Bi3+-Eu3+ dual luminescence system, and, regardless of changes in the Bi3+/Eu3+ concentration or excitation wavelength, a single matrix white light phosphor was realized. Through calculations, the activation energy of the phosphor doped with 2.5%Eu3+ was found to be 0.257 eV, which is higher than the activation energy of some common compounds. This indicates that the phosphor has good application prospects in the field of solid-state lighting. It is worth noting that based on the different thermal response behaviors of Bi3+ and Eu3+, when the Eu3+ content is fixed at 1%, the maximum relative sensitivity of the optical thermometer based on its fluorescence intensity ratio is about 1.46% K-1 at 383 K, which is higher than that of Bi3+ and Eu3+ co-doped phosphors previously reported. We also obtained a high absolute sensitivity of 0.00139 K-1 at 403 K. Therefore, we also studied the thermal sensitivity of Bi3+ and Er3+ co-doped solid solutions. The results show that this solid-solution phosphor has far-reaching application prospects in the temperature sensing field.

8.
Dalton Trans ; 50(20): 7026-7040, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-33949534

RESUMEN

Most praseodymium-doped red-emitting phosphors need high-temperature synthesis conditions with a reducing atmosphere. The niobate matrix selected in this work provides a sufficient electron-rich-site environment for praseodymium through charge migration, and praseodymium can be self-reduced in air atmosphere, which is safe and environmentally friendly. By building the [NbO6] group → Pr3+ energy transfer and finely modifying the doping concentration of Pr3+ ions, we constructed a dual-luminescence-system of the [NbO6] group and Pr3+. Thereby, optical temperature measurement based on fluorescence intensity ratio (FIR) technology of Pr3+ ions and [NbO6] groups was carried out using non-thermal coupling pairs, through the Boltzmann fitting and integral calculation, the maximum Sr and Sa values were 2.25% K-1 and 0.0049 K-1 at 403 K and 443 K, respectively, the Sr value is four times that obtained from the thermal coupling of Pr3+ ions, which exceeded most values previously reported for the fluorescence powder. Accordingly, we also studied the thermal sensitivity of Er3+ ions and Eu3+ ions mono-doped CaNb2O6 substrates. Results reveal that CaNb2O6:Pr3+/Er3+/Eu3+ phosphors have splendid temperature sensitivity and have far-reaching application prospects in the field of temperature measurements.

9.
Support Care Cancer ; 27(4): 1443-1448, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30206725

RESUMEN

PURPOSE: The causes of anemia and the common side effects of cancer are multifactorial. Malnutrition is one of the alleged components of the aforementioned complications. This study planned to investigate the relationship among biochemical markers, Patient-Generated Subjective Global Assessment (PG-SGA), and anemia in cancer patients. METHODS: This analysis consisted of 234 patients who were enlisted in the Department of Oncology of the First Hospital of Shanxi Medical University between December 2016 and October 2017. The groups were divided into anemic and non-anemic patients. The gathered data primarily discussed the patients' basic information, specifically the age, gender, smoking, alcohol consumption, and nutritional status based on levels of serum biochemical markers and PG-SGA scores. RESULTS: Among the participants, 31.2% of the cancer patients were diagnosed with anemia whereas, according to the scores of PG.SGA, 65.0% of patients experienced malnourishment. The anemia was significantly associated with biochemical markers, expecting a transferrin in univariable analyses. Binary logistic regression analysis between anemic cancer patients and non-anemic cancer patients suggested that high PG-SGA score (odds ratio 1.082; 95% CI 1.027-1.141) implied the risk factor for anemia, and high PG-SGA scores could potentially increase the risk of anemia. The multiple regression analysis showed that hemoglobin concentration (OR 0.575; 95% CI 0.450-0.736) and PG-SGA score (OR 1.231; 95% CI 1.013-1.496) were linked to anemia. However, total protein, albumin, prealbumin, serum iron, transferrin, and transferrin saturation lacked a strong relationship with anemia. CONCLUSION: Anemia prevailed in cancer patients, as nutritionally assessed by PG-SGA, while hemoglobin established a linkage with anemia as they could provide extra predictive information about anemia in patients diagnosed with cancer.


Asunto(s)
Anemia/diagnóstico , Biomarcadores/análisis , Neoplasias/diagnóstico , Evaluación Nutricional , Medición de Resultados Informados por el Paciente , Adulto , Anciano , Anemia/etiología , Estudios Transversales , Femenino , Humanos , Masculino , Desnutrición/diagnóstico , Desnutrición/epidemiología , Persona de Mediana Edad , Neoplasias/complicaciones , Neoplasias/epidemiología , Estado Nutricional , Pronóstico , Factores de Riesgo
10.
Anal Chem ; 90(2): 1068-1071, 2018 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-29286242

RESUMEN

Electrochemical stripping analysis (ECSA) is a promising method for metal ions detection. However, the low sensitivity and poor reproducibility limits its practical applications. The combination with other powerful detection techniques to address these concerns is highly desirable. Herein, the anodic stripping method and photoelectrochemical (PEC) technique are integrated into a new detection platform of PEC stripping analysis (PECSA) with bismuth vanadate (BiVO4) as both optoelectronic material and an electrochemical enrichment candidate. The new PECSA strategy presents high sensitivity and excellent reproducibility; in addition, inherited from the ECSA, this strategy also offers new selectivity dimensions through the potential-dependent response and thus implements reproducible, sensitive, and selective detection of silver ion (Ag+) in real biological and environmental samples. The success of PECAS strategy shed light on the rational combination of various analysis techniques for versatile applications.

11.
ACS Nano ; 11(10): 10303-10312, 2017 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-28898052

RESUMEN

Solar-driven overall water splitting is highly desirable for hydrogen generation with sustainable energy sources, which need efficient, earth-abundant, robust, and bifunctional electrocatalysts for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Herein, we propose a heterogeneous bimetallic phosphide/sulfide nanocomposite electrocatalyst of NiFeSP on nickel foam (NiFeSP/NF), which shows superior electrocatalytic activity of low overpotentials of 91 mV at -10 mA cm-2 for HER and of 240 mV at 50 mA cm-2 for OER in 1 M KOH solution. In addition, the NiFeSP/NF presents excellent overall water splitting performance with a cell voltage as low as 1.58 V at a current density of 10 mA cm-2. Combining with a photovoltaic device of a Si solar cell or integrating into photoelectrochemical (PEC) systems, the bifunctional NiFeSP/NF electrocatalyst implements unassisted solar-driven water splitting with a solar-to-hydrogen conversion efficiency of ∼9.2% and significantly enhanced PEC performance, respectively.

12.
Chem Commun (Camb) ; 53(63): 8898-8901, 2017 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-28740992

RESUMEN

In this communication, we report the first demonstration of an efficient photoelectrochemical aptasensor based on sputtering Au nanoparticle-modified nanoporous BiVO4 for the excellent sensitive and selective detection of thrombin with a low detection limit of 0.5 pM and a large linear range.


Asunto(s)
Bismuto/química , Técnicas Electroquímicas , Oro/química , Nanopartículas del Metal/química , Trombina/análisis , Vanadatos/química , Tamaño de la Partícula , Procesos Fotoquímicos , Porosidad , Propiedades de Superficie
13.
Biosens Bioelectron ; 87: 396-403, 2017 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-27589402

RESUMEN

For implementing sensitive and selective detection of biological molecules, the biosensors are been designed more and more complicated. The exploration of detection platform in a simple way without loss their sensitivity and selectivity is always a big challenge. Herein, a prototype of recognition biomolecule unit-free photoelectrochemical (PEC) sensing platform with self-cleaning activity is proposed with TiO2 nanotube photonic crystal (TiO2 NTPCs) materials as photoelectrode, and dopamine (DA) molecule as both sensitizer and target analyte. The unique adsorption between DA and TiO2 NTPCs induces the formation of charge transfer complex, which not only expends the optical absorption of TiO2 into visible light region, thus significantly boosts the PEC performance under illumination of visible light, but also implements the selective detection of DA on TiO2 photoelectrode. This simple but efficient PEC analysis platform presents a low detection limit of 0.15nm for detection of DA, which allows to realize the sensitive and selective determination of DA release from the mouse brain for its practical application after coupled with a microdialysis probe. The DA functionalized TiO2 NTPCs PEC sensing platform opens up a new PEC detection model, without using extra-biomolecule auxiliary, just with target molecule naturally adsorbed on the electrode for sensitive and selective detection, and paves a new avenue for biosensors design with minimalism idea.


Asunto(s)
Química Encefálica , Dopamina/análisis , Técnicas Electroquímicas/métodos , Nanotubos/química , Titanio/química , Animales , Técnicas Biosensibles/métodos , Cristalización , Luz , Masculino , Ratones , Modelos Moleculares , Nanotubos/ultraestructura , Ratas Sprague-Dawley
14.
ACS Appl Mater Interfaces ; 8(45): 30972-30979, 2016 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-27791348

RESUMEN

Photoelectrochemical (PEC) water splitting is a promising technique for sustainable hydrogen generation. However, PEC performance on current semiconductors needs further improvement. Herein, a phosphorus cation doping strategy is proposed to fundamentally boost PEC performance on TiO2 nanotube photonic crystal (TiO2 NTPC) photoelectrodes in both the visible-light region and full solar-light illumination. The self-supported P-TiO2 NTPC photoelectrodes are fabricated by a facile two-step electrochemical anodization method and subsequent phosphidation treatment. The Ti4+ is partially replaced by P cations (P5+) from the crystal lattice, which narrows the band gap of TiO2 and induces charge imbalance by the formation of Ti-O-P bonds. We believe the combination of unique photonic nanostructures of TiO2 NTPCs and P cation doping strategy will open up a new opportunity for enhancing PEC performance of TiO2-based photoelectrodes.

15.
Anal Chem ; 88(15): 7724-9, 2016 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-27377605

RESUMEN

In this work, we clearly demonstrate for the first time the use of transition-metal phosphides to set up a new cathodic analysis platform for sensitive and selective electrochemical nonenzymatic detection of H2O2. With the help of a facile topotactic conversion method, the noble metal-free electrocatalyst of copper(I) phosphide nanowires on three-dimensional porous copper foam (Cu3P NWs/CF) is fabricated with electrochemical anodized Cu(OH)2 NWs as precursor. The Cu3P NWs/CF-based sensor presents excellent electrocatalytic activity for H2O2 reduction with a detection limit of 2 nM, the lowest detection limit achieved by noble-metal free electrocatalyst, which guarantees the possibility of sensitive and reliable detection of H2O2 release from living tumorigenic cells, thus showing the potential application as a sensitive cancer cell detection probe.


Asunto(s)
Cobre/química , Técnicas Electroquímicas , Peróxido de Hidrógeno/análisis , Nanocables/química , Animales , Catálisis , Dopamina/análisis , Electrodos , Glucosa/análisis , Límite de Detección , Ratones , Porosidad , Células RAW 264.7
16.
Chem Commun (Camb) ; 52(24): 4541-4, 2016 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-26935068

RESUMEN

In this communication, we report for the first time the demonstration of a lithium ion intercalation strategy to significantly enhance the photoelectrochemical water splitting performance on 3-dimensional vertical hierarchical top-porous-bottom-tubular TiO2 nanotubes on a fabricable titanium mesh.

17.
Sci Rep ; 5: 16115, 2015 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-26522446

RESUMEN

In this work, we proposed to utilize three-dimensional porous copper foam (CF) as conductive substrate and precursor of in-situ growth CuO nanowires (NWs) for fabricating electrochemical nonenzymatic glucose sensors. The CF supplied high surface area due to its unique three-dimensional porous foam structure, and thus resulted in high sensitivity for glucose detection. The CuO NWs/CF based nonenzymatic sensors presented reliable selectivity, good repeatability, reproducibility, and stability. In addition, the CuO NWs/CF based nonenzymatic sensors have been employed for practical applications, and the glucose concentration in human serum was measured to be 4.96 ± 0.06 mM, agreed well with the value measured from the commercial available glucose sensor in hospital, and the glucose concentration in saliva was also estimated to be 0.91 ± 0.04 mM, which indicated that the CuO NWs/CF owned the possibility for noninvasive glucose detection. The rational design of CuO NWs/CF provided an efficient strategy for fabricating of electrochemical nonenzymatic biosensors.


Asunto(s)
Cobre/química , Glucosa/química , Nanocables/química , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Electroquímica/métodos , Electrodos , Humanos , Límite de Detección , Oxidación-Reducción , Porosidad , Reproducibilidad de los Resultados , Saliva/química , Suero/química
18.
Nanoscale ; 7(47): 19894-8, 2015 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-26450687

RESUMEN

In this communication, a new class of photonic materials, namely, two-dimensional titanium oxide-based photonic crystals, are proposed and were fabricated with an electrochemical anodization method. The high structural periodicity of the nanostructures, and the feasible variability of the chemical compositions help to realize tunable photonic bandgaps for selective light absorption in broad wavelength regions.

19.
Anal Chem ; 87(20): 10491-7, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26389972

RESUMEN

In this work, we clearly demonstrate for the first time the use of a p-type semiconductor, Cu2O, as the core unit of a photocathode to set up a new photocathodic analysis platform. With the help of a facile protection strategy, the Cu2O photocathode presented efficient photoelectrochemical performance for H2O2 sensing with a detection limit of 0.15 µM, which allowed the new photocathodic analysis platform to detect H2O2 released from living tumorigenic cells, thus demonstrating its potential application as a sensitive cancer detection probe. The protected TiO2 layer was coated on Cu2O to form a quasi-core/shell structure (TiO2@Cu2O) through a facile sol-gel method, which significantly enhanced the photostability, comparable to the TiO2@Cu2O samples prepared by a complicated atomic layer deposition method. In this new photocathodic analysis platform, the semiconductive metal oxides accomplish a job usually completed by conductive noble metals in an electroanalysis process. We believe that this photocathodic detection strategy opens up a new detection approach, extends the application range of semiconductor materials, and thus sheds light on the further fusing of photoelectrochemical technique with analytical methods.


Asunto(s)
Cobre/química , Técnicas Electroquímicas , Peróxido de Hidrógeno/análisis , Titanio/química , Línea Celular Tumoral , Supervivencia Celular , Células/citología , Células/metabolismo , Técnicas Electroquímicas/instrumentación , Electrodos , Humanos , Peróxido de Hidrógeno/metabolismo , Estructura Molecular , Tamaño de la Partícula , Procesos Fotoquímicos , Semiconductores , Propiedades de Superficie
20.
Chem Commun (Camb) ; 51(85): 15498-501, 2015 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-26382019

RESUMEN

In this communication, a new photoelectrochemical aptasensor with Au nanoparticle functionalized self-doped TiO2 nanotube arrays (Au/SD-TiO2 NTs) as the core sensing unit and aptamers as the recognition unit was set up to accomplish the sensitive and selective detection of kanamycin with the lowest detection limit of 0.1 nM.


Asunto(s)
Oro/química , Kanamicina/análisis , Nanopartículas del Metal/química , Nanotubos/química , Titanio/química , Electrodos , Tamaño de la Partícula , Procesos Fotoquímicos , Propiedades de Superficie
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