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1.
Analyst ; 149(8): 2291-2298, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38511612

RESUMEN

Building a high-performance sensing platform is the key to developing sensitive sensors. Herein, a highly sensitive self-powered electrochemical sensor (SPES) was constructed using a WO3·H2O film as the cathode prepared by a hydrothermal method and Zn as the anode, and it could be applied to sensitive detection of microcystin (MC-RR). The WO3·H2O film with a larger specific surface area could boost the oxygen reduction reaction (ORR), which could achieve signal amplification and significantly increase the sensitivity of the sensors. Under the optimal conditions, there was a good linear relationship between the increased electrical power density and the logarithm of MC-RR concentration with a detection limit of 1.31 × 10-15 M (S/N = 3). This method had good anti-interference ability and stability when applied to the determination of MC-RR content in actual samples, which could boost the potential application of electrochemical sensors in the field of environmental monitoring.

2.
Analyst ; 149(6): 1746-1752, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38349197

RESUMEN

In this work, the supersensitive and selective determination of lincomycin (Lin) was achieved using a novel electroluminescent (ECL) aptasensor based on the synergistic integration of gold functionalized upconversion nanoparticles (UCNPs) and thiolated 3,4,9,10-perylene tetracarboxylic acid (PTCA). The integration of two luminophores of UCNPs and PTCA combined the merits of the cathodoluminescence stability of UCNPs and the high quantum yield of PTCA, which significantly promoted the ECL signal and analytical performance of the proposed sensor. The introduction of gold nanoparticles in UCNPs can not only improve the conductivity and ECL performance of UCNPs but also cause them to easily integrate with thiolated PTCA (t-PTCA) via an Au-S bond. The ECL signal of UCNPs@Au/t-PTCA/GCE was almost twice as strong as that of t-PTCA/GCE and tenfold higher than that of UCNPs@Au/GCE. Because of the non-conductive protein of the Lin aptamer, the ECL intensity of apt/UCNPs@Au/t-PTCA/GCE noticeably decreased. In the presence of Lin, the aptamer was pulled down from the sensing interface, resulting in the recovery of the ECL intensity of the sensor. Under optimal conditions, our proposed sensor can quantify the concentration of Lin in the range from 1.0 × 10-15 to 1.0 × 10-7 M with a low detection limit of 2.4 × 10-16 M (S/N = 3), exhibiting high sensitivity and specificity for the determination of Lin.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanopartículas del Metal , Perileno/análogos & derivados , Nanopartículas del Metal/química , Oro/química , Aptámeros de Nucleótidos/química , Lincomicina , Técnicas Biosensibles/métodos , Límite de Detección , Mediciones Luminiscentes , Técnicas Electroquímicas/métodos
3.
J Fluoresc ; 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38270796

RESUMEN

The traditional methods for identifying water sources in coal mines lack the ability to quickly detect water sources and are prone to causing secondary pollution of samples. In contrast, laser induced fluorescence (LIF) technology has been introduced for the identification of coal mine water sources due to its high sensitivity and real-time performance. However, extreme learning machine (ELM) have shortcomings in randomly selecting weights and biases. The Beluga Whale Optimization (BWO) algorithm has efficient optimization capability, global search capability, adaptability and parallelism, and can find the optimal weights and biases in a short time. The combination of LIF technology and BWO-ELM model can be applied to quickly identify the welling water source in coal mine. Select sandstone water and old goaf water from the Huainan mining area as experimental samples, and mix them in different proportions to prepare 7 mixed water samples for testing. Utilize LIF technology to obtain spectral curve images, preprocess them with polynomial smoothing algorithm (SG) and spectral multiple scattering correction (MSC), and perform dimensionality reduction using factor analysis (FA) and linear discriminant analysis (LDA) methods. Finally, construct ELM models, Long Short Term Memory (LSTM) models, BWO-ELM models, and Particle Swarm Optimization Extreme Learning Machine(PSO-ELM) models for the dimensionality reduced data. In order to improve the reliability and accuracy of the results, the experimental results were kept to 5 decimal places. From the experimental results, it can be seen that SG-LDA-BWO-ELM has the best fitting effect, with a fitting coefficient of 0.99990, a root mean square error of 0.00041, a mean square error approaching 0, and an average absolute error of 0.00021. It has the best convergence and the smallest absolute error among all models, making it the most suitable for identifying mine water inrush. It is of great significance for preventing and controlling mine water disasters and ensuring coal mine production safety.

4.
Phys Chem Chem Phys ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38952230

RESUMEN

Rational coupling of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) catalysts is extremely important for practical overall water splitting; however, it is still challenging to construct such bifunctional heterostructures. Herein, a CeO2/W@Co-MOF/NF bifunctional electrocatalyst was prepared via a two-step in situ growth method involving an electrodeposition process. The incorporation of the W element enhanced the electronic interaction and enlarged the electrochemical surface area. After the electrodeposition of CeO2, the obtained CeO2/W@Co-MOF/NF possessed abundant heterointerfaces with a modulated local distribution, which promoted water dissociation and rapid electrocatalytic kinetics. In particular, it required very low overpotentials of 239 mV and 87 mV to reach a current density of 10 mA cm-2 in OER and HER, respectively. A corresponding alkaline electrolysis cell afforded a cell voltage of 1.54 V at 10 mA cm-2 to boost overall water splitting. This work provides a feasible strategy to fabricate MOF-based complexes and explores their possible use as bifunctional catalysts toward overall water splitting.

5.
Phys Chem Chem Phys ; 26(9): 7618-7626, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38363116

RESUMEN

Poor conductivity of the metal-organic frameworks (MOFs) limits their applications in overall water splitting. Surface sulfur (S) doping transition metal hydroxides would effectively improve the conductivity and adjust the electronic structure to generate additional electroactive sites. Herein, we fabricated a Ni-S/Co-MOF/NF catalyst by electroplating a Ni-S film on the 3D flower-like Co-MOF. Because the 3D flower-like structures are covered in Ni foam, the high exposure of active sites and good conductivity are obtained. Moreover, the synergistic effect between Ni-S and Co-MOF contributes to the redistribution of electrons in the catalyst, which can then optimize the catalytic performance of the material. The obtained 3D flower-like Ni-S/Co-MOF/NF demonstrates excellent activity toward both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) in 1 M KOH, which only requires a low overpotential of 248 mV@10 mA cm-2 for the OER and 127 mV@10 mA cm-2 for the HER, respectively. At a current density of 10 mA cm-2, the Ni-S/Co-MOF/NF‖Ni-S/Co-MOF/NF requires a low cell voltage of 1.59 V to split overall water splitting.

6.
Phys Chem Chem Phys ; 26(12): 9096-9111, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38456310

RESUMEN

As one of the most promising energy storage devices, supercapacitors exhibit a higher power density than batteries. However, its low energy density usually requires high-performance electrode materials. Although the RuO2 material shows desirable properties, its high cost and toxicity significantly limit its application in supercapacitors. Recent developments demonstrated that Co-based materials have emerged as a promising alternative to RuO2 for supercapacitors due to their low cost, favorable redox reversibility and environmental friendliness. In this paper, the morphological control and performance engineering of Co-based materials are systematically reviewed. Firstly, the principle of supercapacitors is briefly introduced, and the characteristics and advantages of pseudocapacitors are emphasized. The special forms of cobalt-based materials are introduced, including 1D, 2D and 3D nanomaterials. After that, the ways to enhance the properties of cobalt-based materials are discussed, including adding conductive materials, constructing heterostructures and doping heteroatoms. Particularly, the influence of morphological control and modification methods on the electrochemical performances of materials is highlighted. Finally, the application prospect and development direction of Co-based materials are proposed.

7.
Anal Chem ; 95(34): 12595-12599, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37522904

RESUMEN

Self-powered electrochemical sensors, which can function without external electricity, are incredibly valuable in the realm of sensing. However, most of the present testing methods are normally confined to high environmental requirements, restricted lighting conditions, and temperature differences. Herein, an innovative self-powered electrochemical sensor was successfully developed based on hydrovoltaic effect coupling with capacitor amplification. Due to the combined merits from the two-dimensional transition metal carbides and nitrides (MXene)-polyaniline (PANI) with high surface potential and good hydrophilicity, and the capacitor amplification strategy, the device could harvest electric energy from water evaporation and displayed a high short circuit current value. Under optimal conditions, the proposed self-powered electrochemical sensor presented excellent sensitivity and high specificity for enrofloxacin (ENR) detection in the concentration range from 1 fM to 1 nM with a detection limit of 0.585 fM. Such a proposed sensor also has the advantages of environmental friendliness and ease of use, which is an ideal choice for accurately and precisely detecting ENR in real samples. The mode of such electrochemical detection outlined in this technical note implements a breakthrough in designing self-powered electrochemical sensors, providing a rational basis for development of a diversified sensing platform.

8.
Analyst ; 148(10): 2335-2342, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37186001

RESUMEN

Trilobatin is a flavonoid that has wide application prospects due to its various pharmacological effects, such as anti-inflammation and anti-oxidation. In this work, a novel electrochemical sensor based on gold nanobipyramids (AuNBs) and L-cysteine (L-cys) was constructed for the sensitive and selective determination of trilobatin. The AuNBs, which were prepared by a seed-mediated growth method, had large specific surface areas and excellent electrical conductivity. A layer of L-cys film, which provided more active sites through the amino and hydroxyl groups, was modified on the surface of the AuNBs by electropolymerization. Significantly, the Au-S bond between the L-cys film and AuNBs could improve the stability of the sensor and it exhibited satisfactory electrocatalytic oxidation activity for trilobatin. Under optimized conditions, the sensor based on poly-L-cys/AuNBs/GCE was used to determine trilobatin by differential pulse voltammetry (DPV). Two wide linear ranges between the current peak and the concentration of trilobatin were obtained in the range from 5 to 100 µM and 100 to 1000 µM, and the low detection limit (LOD) was up to 2.55 µM (S/N = 3). The sensor demonstrated desirable reproducibility, stability, and selectivity and was applied to detect real trilobatin samples extracted from Lithocarpus polystachyus Rehd.'s leaves, showing recoveries of 98.36%-104.96%, with satisfactory results.


Asunto(s)
Cisteína , Oro , Oro/química , Reproducibilidad de los Resultados , Oxidación-Reducción , Técnicas Electroquímicas , Electrodos
9.
Analyst ; 148(18): 4470-4478, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37574902

RESUMEN

In this work, a super-sensitive electrochemiluminescence (ECL) aptamer sensor was constructed using a multiple signal amplification strategy to realize ultra-sensitive detection of di-(2-ethylhexyl) phthalate (DEHP). The incorporation of a highly efficient electrocatalytic metal-organic framework (NH2-Zr-MOF) and graphdiyne (GDY) composite has significantly enhanced the overall electrochemically active surface area, facilitating electron transfer during the entire electrochemical reaction process, and the large number of pores in graphdiyne and NH2-Zr-MOF limited a series of redox reactions within a certain range. This resulted in the generation of a greater number of SO4˙- radicals, thereby boosting the ECL intensity of the GDY in the K2S2O8 system. To increase the performance of the sensor even further, sodium ascorbate (NaAsc) as an accelerator was added to the co-reactant system. Additionally, nitrogen micro-nano bubbles with higher stability and stronger mass transfer have been introduced into the ECL system for the first time. Based on these, the aptamer as the recognition element realized the ultra-sensitive detection of DEHP in the linear range of 1.0 × 10-12 to 1.0 × 10-4 mg mL-1 with the limit of detection (LOD) of 2.43 × 10-13 mg mL-1. In summary, we have utilized the electrocatalytic activity of the porous MOF and the reducing capability of sodium ascorbate to enhance the ECL emission of GDY, which has been successfully applied to the detection of DEHP in water samples.

10.
Analyst ; 148(23): 6087-6096, 2023 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-37916516

RESUMEN

Nowadays, bacterial resistance caused by the abuse of antibiotics has become a worldwide problem. In this work, a quinolone antibiotic, enrofloxacin (ENR), was rapidly monitored by combining a selective molecular imprinting polymer (MIP) with the electrochemiluminescence (ECL) method. Zn-PTC, a novel zinc-based metal-organic framework (MOF) that has a large specific surface area and ultra-high luminous efficiency, was used as the ECL luminophore. Chitosan (CHIT) was used to contact the specific surface area of molecularly imprinted polymer films and further improved the detection sensitivity. Subsequently, the molecularly imprinted polypyrrole was electropolymerized on the surface of the Zn-PTC and CHIT modified glassy carbon electrode (GCE). The specific sites that could target recombining ENR were shaped on the surface of MIP after extracting the ENR templates. The specific concentrations of ENR could be detected according to the difference in ECL intensity (ΔECL) between the eluting and rebinding of ENR. After optimization, a good linear response of ΔECL and a logarithm of specific ENR concentrations could be obtained in the range of 1.0 × 10-12-1.0 × 10-4 mol L-1, with a detection limit of 9.3 × 10-13 mol L-1 (S/N = 3). Notably, this study provided a rapid, convenient, and cheap method for the detection of ENR in actual samples.


Asunto(s)
Quitosano , Estructuras Metalorgánicas , Polímeros , Enrofloxacina , Pirroles , Zinc , Antibacterianos
11.
Inorg Chem ; 62(31): 12590-12599, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37480341

RESUMEN

In this paper, Pr0.7Sr0.3Co1-xRuxO3 perovskite oxides were synthesized by the sol-gel method as bifunctional catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The overpotentials of PSCR0.05 against HER and OER at 10 mA cm-2 were 319 and 321 mV in alkaline medium, respectively. The Tafel slopes of HER and OER were 87.32 and 118.1 mV/dec, respectively. PSCR0.05 showed the largest electrochemical active area, the smallest charge transfer resistance, and excellent long-term durability. Meanwhile, the PSCR0.05 electrocatalyst was applied for overall water splitting and its cell voltage was maintained at 1.77 V at 10 mA cm-2. The super-exchange interaction between adjacent RuO6-CoO6 octahedra in perovskite made of PSCR0.05 contains sufficient active sites (such as Co2+/Co3+, Ru3+/Ru4+, and O22-/O-). The increase of surface oxygen vacancy and active site is the main reason for the improvement of difunctional catalyst performance. In this work, the electrocatalytic performance of perovskite-type oxides was further optimized by the method of A- and B-site cationic doping regulation, which provides a new idea for perovskite-type bifunctional electrocatalysts.

12.
Inorg Chem ; 62(44): 18189-18197, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37883780

RESUMEN

Recently, transition metal phosphides (TMPs) have been widely explored for the hydrogen evolution reaction (HER) due to their advantaged activity. Nevertheless, the OER performance of TMPs in an alkaline medium is still unsatisfactory. Therefore, interfacial engineering of TMPs to enhance the OER performance is highly desirable. Herein, a Co(OH)2 nanosheet coupled with a CoP sphere supported on nickel foam (NF) is developed by a simple two-step electrodeposition. The large surface area derived from stacked nanosheets and the electronic regulation induced by heterostructure can significantly enhance charge/mass transfer and expose more active sites, thus accelerating the kinetics of the reaction. In addition, the strong electronic interaction between CoP and Co(OH)2 is conducive to the generation of a high valence cobalt center; thus, the electrocatalytic performances toward HER and OER are remarkably improved. Impressively, the optimized CoP/Co(OH)2@NF heterostructure obtains an excellent HER and OER performance with low overpotentials of 76 and 266 mV at 10 mA cm-2, respectively, superior to the commercial Pt/C and RuO2. Moreover, the optimized CoP/Co(OH)2@NF can afford the lowest cell voltage of 1.58 V to achieve 10 mA cm-2 for alkaline overall water splitting and shows outstanding long-term stability.

13.
Mikrochim Acta ; 190(9): 373, 2023 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-37648847

RESUMEN

Ciprofloxacin (CIP), a quinolone antibiotic, was rapidly and sensitively detected by integrating the molecularly imprinted polymer (MIP) with an ultra-sensitive electrochemiluminescence (ECL) method. g-C3N4, a typical polymer semiconductor, exhibited outstanding ECL efficiency and excellent ECL stability after combining with an iron-based metal-organic framework (MIL-101). Subsequently, the molecularly imprinted polypyrrole was electropolymerized on the composites of MIL-101-g-C3N4 modified glassy carbon electrode (GCE). The specific sites that could target rebinding the CIP molecules were formed on the surface of MIP after extracting the CIP templates. The determination of specific concentrations of CIP could be realized according to the difference in ECL intensity (△ECL) between the eluting and rebinding of the CIP. Under optimal conditions, a good linear response of △ECL and the logarithm of CIP concentrations was obtained in the range 1.0 × 10-9 ~ 1.0 × 10-5 mol/L, with a detection limit of 4.5 × 10-10 mol/L (S/N = 3) (the working potential was -1.8 ~ 0 V). The RSD of all points in the calibration plot was less than 5.0% and the real samples recovery was between 98.0 and 104%. This paper displays satisfactory selectivity and sensitivity, providing a rapid, convenient, and cheap method for the determination of CIP in real samples.


Asunto(s)
Estructuras Metalorgánicas , Polímeros , Pirroles , Ciprofloxacina , Polímeros Impresos Molecularmente
14.
Sensors (Basel) ; 23(17)2023 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-37687909

RESUMEN

A uniformly oriented purple membrane (PM) monolayer containing photoactive bacteriorhodopsin has recently been applied as a sensitive photoelectric transducer to assay color proteins and microbes quantitatively. This study extends its application to detecting small molecules, using adenosine triphosphate (ATP) as an example. A reverse detection method is used, which employs AuNPs labeling and specific DNA strand displacement. A PM monolayer-coated electrode is first covalently conjugated with an ATP-specific nucleic acid aptamer and then hybridized with another gold nanoparticle-labeled nucleic acid strand with a sequence that is partially complementary to the ATP aptamer, in order to significantly minimize the photocurrent that is generated by the PM. The resulting ATP-sensing chip restores its photocurrent production in the presence of ATP, and the photocurrent recovers more effectively as the ATP concentration increases. Direct and single-step ATP detection is achieved in 15 min, with detection limits of 5 nM and a dynamic range of 5 nM-0.1 mM. The sensing chip exhibits high selectivity against other ATP analogs and is satisfactorily stable in storage. The ATP-sensing chip is used to assay bacterial populations and achieves a detection limit for Bacillus subtilis and Escherichia coli of 102 and 103 CFU/mL, respectively. The demonstration shows that a variety of small molecules can be simultaneously quantified using PM-based biosensors.


Asunto(s)
Bacteriorodopsinas , Nanopartículas del Metal , Ácidos Nucleicos , Oro , ADN , Adenosina Trifosfato , Escherichia coli
15.
BMC Cancer ; 22(1): 916, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-36002810

RESUMEN

BACKGROUND: Extralevator abdominoperineal excision (ELAPE) has been recommended for treating low rectal cancer due to its potential advantages in improving surgical safety and oncologic outcomes as compared to conventional abdominoperineal excision (APE). In ELAPE, however, whether the benefits of intraoperative position change to a prone jackknife position outweighs the associated risks remains controversial. This study is to introduce a modified position change in laparoscopic ELAPE and evaluate its feasibility, safety and the long-term therapeutic outcomes. METHODS: Medical records of 56 consecutive patients with low rectal cancer underwent laparoscopic ELAPE from November 2013 to September 2016 were retrospectively studied. In the operation, a perineal dissection in prone jackknife position was firstly performed and the laparoscopic procedure was then conducted in supine position. Patient characteristics, intraoperative and postoperative outcomes, pathologic and 5-year oncologic outcomes were analyzed. RESULTS: The mean operation time was 213.5 ± 29.4 min and the mean intraoperative blood loss was 152.7 ± 125.2 ml. All the tumors were totally resected, without intraoperative perforation, conversion to open surgery, postoperative 30-day death, and perioperative complications. All the patients achieved pelvic peritoneum reconstruction without the usage of biological mesh. During the follow-up period, perineal hernia was observed in 1 patient, impaired sexual function in 1 patient, and parastomal hernias in 3 patients. The local recurrence rate was 1.9% and distant metastasis was noted in 12 patients. The 5-year overall survival rate was 76.4% and the 5-year disease-free survival rate was 70.9%. CONCLUSIONS: Laparoscopic ELAPE with modified position change is a simplified, safe and feasible procedure with favorable outcomes. The pelvic peritoneum can be directly closed by the laparoscopic approach without the application of biological mesh.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Laparoscopía , Proctectomía , Neoplasias del Recto , Abdomen/patología , Abdomen/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Humanos , Laparoscopía/efectos adversos , Laparoscopía/métodos , Perineo/cirugía , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
16.
Analyst ; 147(22): 5194-5202, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36250305

RESUMEN

Herein, a novel molecular imprinting polypyrrole electrochemical sensor was fabricated based on a zirconia and carbon core-shell structure (ZrO2@C) and a nitrogen-doped graphene (NPG) modified glassy carbon electrode (GCE) for ultrasensitive recognition of dopamine (DA). The NPG was prepared by a sacrificial-template-assisted pyrolysis method and ZrO2@C was synthesized via annealing treatment of a zirconium-based metal-organic framework (UiO-66). A convenient electropolymerization method was used to prepare the pyrrole (Py) conductive molecularly imprinted polymer (MIP) in the presence of DA. The elution process of DA was performed by a simple overoxidation process under alkaline conditions. Differential pulse voltammetry (DPV) was used to assess the electrochemical performance of the sensors. The MIP-based electrochemical sensor with specific binding sites could be used for selective recognition of DA. Under the optimal conditions, the linear range of such a sensor was 5.0 × 10-9-1.0 × 10-4 mol L-1 and the detection limit was 3.3 × 10-10 mol L-1 (S/N = 3). This sensor exhibited suitable selectivity, stability, and reproducibility, which suggested that it could be a promising candidate for rapid diagnostic methods in dopamine investigations.


Asunto(s)
Grafito , Impresión Molecular , Grafito/química , Polímeros/química , Dopamina/química , Pirroles/química , Carbono/química , Técnicas Electroquímicas/métodos , Nitrógeno , Porosidad , Reproducibilidad de los Resultados , Límite de Detección , Impresión Molecular/métodos , Electrodos
17.
Mikrochim Acta ; 189(9): 313, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-35922727

RESUMEN

A ternary composite material with Au, Co-based organic frameworks (ZIF-67) and perylene derivatives (PTCD-cys) has been synthesized for identification of synthetic cannabinoids. Through contact with Au-S, Au-ZIF-67 increased electrochemiluminescence (ECL) sensitivity and stability and efficiently catalyzed the ECL of PTCD-cys. Compared with the ECL response of PTCD-cys monomer, the ECL signal value of the composite material was significantly increased, and the onset potential of Au-ZIF-67/PTCD-cys favorably shifted more than that of PTCD-cys/GCE. When the target cannabinoid molecule RCS-4 appeared, Au-ZIF-67 captured and immobilized it on the sensor surface by adsorption to achieve target-induced self-enrichment of RCS-4. Under optimal conditions, the ECL sensor was found to be linearly related to the logarithm of the RCS-4 concentration ranging from 3.1 × 10-15 to 3.1 × 10-9 mol/L with a detection limit (LOD) of 6.0 × 10-16 mol/L (S/N = 3). The approach had the advantages of being simple to use, having a high sensitivity, a wide detection range, and good stability, making it a novel platform for RSC-4 detection in public health safety monitoring.


Asunto(s)
Cannabinoides , Nanopartículas del Metal , Catálisis , Técnicas Electroquímicas , Oro , Mediciones Luminiscentes
18.
Diabetologia ; 64(7): 1613-1625, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33842983

RESUMEN

AIMS/HYPOTHESIS: An elevated fasting glucose level in non-diabetic individuals is a key predictor of type 2 diabetes. Genome-wide association studies (GWAS) have identified hundreds of SNPs for fasting glucose but most of their functional roles in influencing the trait are unclear. This study aimed to identify the mediation effects of DNA methylation between SNPs identified as significant from GWAS and fasting glucose using Mendelian randomisation (MR) analyses. METHODS: We first performed GWAS analyses for three cohorts (Taiwan Biobank with 18,122 individuals, the Healthy Aging Longitudinal Study in Taiwan with 1989 individuals and the Stanford Asia-Pacific Program for Hypertension and Insulin Resistance with 416 individuals) with individuals of Han Chinese ancestry in Taiwan, followed by a meta-analysis for combining the three GWAS analysis results to identify significant and independent SNPs for fasting glucose. We determined whether these SNPs were methylation quantitative trait loci (meQTLs) by testing their associations with DNA methylation levels at nearby CpG sites using a subsample of 1775 individuals from the Taiwan Biobank. The MR analysis was performed to identify DNA methylation with causal effects on fasting glucose using meQTLs as instrumental variables based on the 1775 individuals. We also used a two-sample MR strategy to perform replication analysis for CpG sites with significant MR effects based on literature data. RESULTS: Our meta-analysis identified 18 significant (p < 5 × 10-8) and independent SNPs for fasting glucose. Interestingly, all 18 SNPs were meQTLs. The MR analysis identified seven CpGs near the G6PC2 gene that mediated the effects of a significant SNP (rs2232326) in the gene on fasting glucose. The MR effects for two CpGs were replicated using summary data based on the European population, using an exonic SNP rs2232328 in G6PC2 as the instrument. CONCLUSIONS/INTERPRETATION: Our analysis results suggest that rs2232326 and rs2232328 in G6PC2 may affect DNA methylation at CpGs near the gene and that the methylation may have downstream effects on fasting glucose. Therefore, SNPs in G6PC2 and CpGs near G6PC2 may reside along the pathway that influences fasting glucose levels. This is the first study to report CpGs near G6PC2, an important gene for regulating insulin secretion, mediating the effects of GWAS-significant SNPs on fasting glucose.


Asunto(s)
Glucemia/genética , Islas de CpG/genética , Glucosa-6-Fosfatasa/genética , Estudios de Cohortes , Metilación de ADN , Ayuno/sangre , Estudio de Asociación del Genoma Completo , Genómica/métodos , Humanos , Estudios Longitudinales , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo/genética , Taiwán/epidemiología
19.
Analyst ; 146(11): 3493-3499, 2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-33960345

RESUMEN

Black phosphorus quantum dots (BPQDs), as a new type of nanomaterial, have excellent electrical and optical properties. In this work, an efficient monitoring method for kanamycin (KAN) was developed based on a sensitive and selective electrochemiluminescence (ECL) aptasensor. The construction of the ECL illuminant was based on BPQDs loaded on silver-nanoparticle modified high-luminescence polydopamine nanospheres (HLPNs@Ag). HLPNs possessed a large specific surface area and strong adhesion, which could support a great deal of BPQDs. Meanwhile, Ag NPs could accelerate the electron-transfer (ET) rate of the sensor and amplify the ECL signal of the BPQDs. Based on the synergistic enhancement effects between the above materials, the as-fabricated nanocomposites exhibited superior ECL performance. With the assistance of a KAN aptamer, the sensor can detect KAN sensitively and selectively. Under optimal conditions, the aptasensor could detect KAN in a wide linear range from 1 × 10-12 to 1.0 × 10-7 M with a detection limit of 1.7 × 10-13 M (S/N = 3). More importantly, this ultra-sensitive and rapid ECL aptasensor-based KAN detection system provided excellent applicability for the monitoring of environmental safety.

20.
Analyst ; 146(6): 2029-2036, 2021 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-33528465

RESUMEN

In this study, a sensitive and effective monitoring method for ractopamine (RAC) was developed based on a sensitive electrochemiluminescence (ECL) aptasensor. Here, we employed a perylene derivative (PTC-PEI) with a Cu-based metal-organic framework (HKUST-1), which could accelerate the electron-transfer (ET) rate and strengthen interactions by the amido bond, resulting in enhanced ECL sensitivity and stability. Astonishingly, compared with the response of PTC-PEI and complex, the ECL signal of the MOF-based ECL material was noticeably raised by 6 times higher than that of PTC-PEI. HKUST-1 exhibited an excellent catalytic effect towards the electrochemical reduction process of S2O82-, thus allowing more sulfate radical anions (SO4˙-) to be generated. The strong ECL intensity of HKUST-1/PTC-PEI not only stemmed from the fixation of PTC-PEI that utilized its excellent film-forming abilities but also originated from the high porosity of HKUST-1 that carried more luminophores able to be excited. Satisfyingly, in the presence of the target molecule RAC, we observed an obvious quenching effect of signal, which could be attributed to aptamer recognition resulting in RAC being specifically captured on the electrode. Under optimal conditions, the developed sensor for the RAC assay displayed a desired linear range of 1.0 × 10-12-1.0 × 10-6 M and a low detection limit of 6.17 × 10-13 M (S/N = 3). This ECL sensor showed high sensitivity, good stability and excellent selectivity. More importantly, the proposed aptasensor exhibited excellent determination towards RAC detection and potential practical utility for real samples.

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