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1.
Dalton Trans ; 52(34): 11773-11779, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37591806

RESUMO

A multi-responsive Cd(II) coordination polymer (1) has been constructed by introducing a viologen derivative as both the framework backbone and ligand side pendant. Notably, compound 1 exhibits intriguing properties, including photochromism, methanol-assisted photochromism and chemochromism to ammonia. Furthermore, compound 1 also displays fluorescence pH sensing ability in a wide pH range.

2.
Food Chem ; 429: 136955, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37490817

RESUMO

Pectin extraction is generally an energy-intensive industrial process, while on the other hand their extraction methods vary from different sources. Starting with that perspective, pectin (WSP) containing ultra-low degree of methylation (31.08 ± 1.27%) from dragon fruit peel (DFP) was extracted by using pure water at room temperature. WSP, dominant in DFP (17.13 ± 1.01%), showed both a high molecular weight and a wide molecular weight distribution, while the yield of the rest acid-soluble pectin (HAP) from DFP residue was only 5.22 ± 0.76%. Furthermore, WSP can stabilize emulsions over a wide range of concentrations and oil phases, especially HIPE. Therefore, the hypothesis was verified that the pectin-rich extract from dragon fruit peel with excellent emulsifying properties could be simply extracted by pure water. This environmentally-friendly and energy-saving extraction method provides a new insight to increase the additional value of dragon fruit peel produced in food processing.


Assuntos
Frutas , Pectinas , Emulsificantes , Emulsões , Cânfora , Mentol , Água
3.
Front Nutr ; 10: 1083483, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875840

RESUMO

Background: The incidence of refeeding syndrome (RFS) in critically ill patients is high, which is detrimental to their prognoses. However, the current status and risk factors for the occurrence of RFS in neurocritical patients remain unclear. Elucidating these aspects may provide a theoretical basis for screening populations at high risk of RFS. Methods: A total of 357 patients from January 2021 to May 2022 in a neurosurgery ICU of a tertiary hospital in China were included using convenience sampling. Patients were divided into RFS and non-RFS groups, based on the occurrence of refeeding-associated hypophosphatemia. Risk factors for RFS were determined using univariate and logistic regression analyses, and a risk prediction model for RFS in neurocritical patients was developed. The Hosmer-Lemeshow test was used to determine the goodness of fit of the model, and the receiver operator characteristic curve was used to examine its discriminant validity. Results: The incidence of RFS in neurocritical patients receiving enteral nutrition was 28.57%. Logistic regression analyses showed that history of alcoholism, fasting hours, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, Sequential Organ Failure Assessment (SOFA) scores, low serum albumin, and low baseline serum potassium were risk factors of RFS in neurocritical patients (p < 0.05). The Hosmer-Lemeshow test showed p = 0.616, and the area under the ROC curve was 0.791 (95% confidence interval: 0.745-0.832). The optimal critical value was 0.299, the sensitivity was 74.4%, the specificity was 77.7%, and the Youden index was 0.492. Conclusion: The incidence of RFS in neurocritical patients was high, and the risk factors were diverse. The risk prediction model in this study had good predictive effects and clinical utility, which may provide a reference for assessing and screening for RFS risk in neurocritical patients.

4.
Front Neurol ; 14: 1259484, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38187148

RESUMO

Purpose: This study aimed to clarify the effect of early glucocorticoid (GC) application on achieving minimal manifestation (MM) status or better in the treatment of myasthenia gravis (MG) in the early clinical phase. Methods: A retrospective analysis was performed using data from 336 patients with MG who received GC therapy from January 2015 to September 2022 in the Zhengzhou University Henan Institute of Medical and Pharmaceutical Sciences Myasthenia Gravis Biobank (ZMB). Patients were divided into two groups: the early mono-GC group (treated with GC within 6 months of MG onset) and the delayed mono-GC group. Results: Kaplan-Meier analysis showed that the early mono-GC group achieved MM status earlier and more frequently than the delayed mono-GC group (log-rank test, p = 0.0082; hazard ratio [HR], 1.66; p = 0.011). The early mono-GC group had a lower maintenance oral GC dose than the delayed mono-GC group. In multivariate Cox regression analysis, early mono-GC (HR, 1.50; p = 0.043), early-onset MG (EOMG) (HR, 1.74; p = 0.034), and ocular MG (OMG) (HR, 1.90; p = 0.007) were associated with MM status or better. In conclusion, early mono-GC, EOMG, and OMG were positive predictors of treatment goals. In EOMG, OMG, and acetylcholine receptor antibody-positive MG (AChR-MG) subgroups, the maintenance oral GC doses in the early mono-GC group were significantly lower than the doses in the delayed mono-GC group (p < 0.05). Conclusion: Early intervention with GC led to better long-term outcomes and reduced the necessary maintenance dose of oral GC for patients with MG. EOMG and OMG were positive predictors of MM status or better with mono-GC.

5.
Polymers (Basel) ; 14(21)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36365598

RESUMO

The exploding foil initiator (EFI) system has been extensively used in ignition and detonation sequences and proved to be of high safety and reliability. Polyimide is considered the ideal flyer material for EFI due to its excellent performance, including thermal stability, outstanding mechanical properties, high radiation resistance, and excellent dielectric properties. In this study, we prepared the EFI based on a polyimide (ODPA-ODA) flyer, which is spin-coated and solidified on patterned copper film in situ. The electric explosion test shows that the prepared EFI has good working performance, and the 4000 V working voltage drove the flyer to reach a maximum velocity of 5096 m/s. The polyimide morphology and chemical structure after the electric explosion was observed by microscope, SEM, XPS, and FTIR, which showed that the polyimide flyer underwent thermal deformation and complex chemical reactions during an electric explosion. A large number of polyimide bonds broke to form new carbonyl compounds, and the opening of aromatic rings was accompanied by the formation of aliphatic hydrocarbon chains. The morphology and chemical structure analysis after the electric explosion test will lay a foundation for us to further understand the working principle and evolution process of polyimide (ODPA-ODA) flyer.

6.
Front Public Health ; 10: 930653, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937248

RESUMO

Background: During the Coronavirus (COVID-19) pandemic, wearing masks became crucial for preventing infection risk and maintaining basic health. Therefore, it is necessary to understand the behavioral characteristics of the mask-wearing public to provide theoretical reference for the prevention and control of COVID-19. Methods: We conducted a nationwide survey on the mask-wearing behavior of the public and their health literacy levels by distributing electronic questionnaires. Univariate and logistic regression analyses were performed to determine the factors influencing mask-wearing behavior. Pearson's correlation was used to analyze the correlation between mask-wearing behaviors and e-health literacy. Results: A total of 1,972 valid questionnaires were collected; 99.8% of the public wore masks when going out and 59.2% showed good mask-wearing behavior. Most people choose to wear disposable medical masks (61.3%), followed by medical surgical masks (52.9%). All participants indicated that they had understood the information on how to use masks, and most obtained it through social media (61.8%). The average of the e-health literacy scores of those with good mask-wearing behavior was significantly higher than those with poor mask-wearing behavior (P < 0.05), and each item score of the former's e-health literacy was significantly higher than the latter (P < 0.05). Further, there was a positive correlation between mask-wearing behavior and e-health literacy (R = 0.550, P < 0.05). Logistic regression analysis showed that seven factors are related to mask-wearing behavior, including gender, place of residence, educational level, work or living environment, marital status, flu symptoms, and whether living with people in home quarantine (P < 0.01). Conclusion: The overall compliance of the public's mask-wearing behavior in China during COVID-19 is good. However, there are shortcomings regarding the selection, use, and precautions. The differences in mask-wearing behavior are related to factors including gender, place of residence, educational level, work or living environment, marital status, presence of flu symptoms, and whether living with people in home quarantine. Higher levels of e-health literacy indicated better mask-wearing behavior. Therefore, it is necessary to strengthen the public's popularization and education regarding the prevention and control of COVID-19.


Assuntos
COVID-19 , Letramento em Saúde , Máscaras , COVID-19/epidemiologia , COVID-19/psicologia , China/epidemiologia , Humanos , SARS-CoV-2
7.
J Neurosci ; 42(32): 6195-6210, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35840323

RESUMO

Mitogen-activated protein kinase kinase kinases (MAP3Ks) dual leucine kinase (DLK) and leucine zipper kinase (LZK) are essential mediators of axon damage responses, but their responses are varied, complex, and incompletely understood. To characterize their functions in axon injury, we generated zebrafish mutants of each gene, labeled motor neurons (MNs) and touch-sensing neurons in live zebrafish, precisely cut their axons with a laser, and assessed the ability of mutant axons to regenerate in larvae, before sex is apparent in zebrafish. DLK and LZK were required redundantly and cell autonomously for axon regeneration in MNs but not in larval Rohon-Beard (RB) or adult dorsal root ganglion (DRG) sensory neurons. Surprisingly, in dlk lzk double mutants, the spared branches of wounded RB axons grew excessively, suggesting that these kinases inhibit regenerative sprouting in damaged axons. Uninjured trigeminal sensory axons also grew excessively in mutants when neighboring neurons were ablated, indicating that these MAP3Ks are general inhibitors of sensory axon growth. These results demonstrate that zebrafish DLK and LZK promote diverse injury responses, depending on the neuronal cell identity and type of axonal injury.SIGNIFICANCE STATEMENT The MAP3Ks DLK and LZK are damage sensors that promote diverse outcomes to neuronal injury, including axon regeneration. Understanding their context-specific functions is a prerequisite to considering these kinases as therapeutic targets. To investigate DLK and LZK cell-type-specific functions, we created zebrafish mutants in each gene. Using mosaic cell labeling and precise laser injury we found that both proteins were required for axon regeneration in motor neurons but, unexpectedly, were not required for axon regeneration in Rohon-Beard or DRG sensory neurons and negatively regulated sprouting in the spared axons of touch-sensing neurons. These findings emphasize that animals have evolved distinct mechanisms to regulate injury site regeneration and collateral sprouting, and identify differential roles for DLK and LZK in these processes.


Assuntos
Axônios , Peixe-Zebra , Animais , Axônios/fisiologia , Leucina/metabolismo , Zíper de Leucina , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Neurônios Motores/metabolismo , Regeneração Nervosa/genética
8.
Nano Lett ; 22(3): 1198-1206, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35080406

RESUMO

Two-dimensional conductive metal-organic frameworks (2D CMOFs) can be regarded as high-performance electrode substances owing to their rich hierarchical porous architecture and excellent electrical conductivity. However, the sluggish kinetics behavior of electrodes within the bulk structure restricts their advances in energy storage fields. Herein, a series of graphene-based mixed-dimensional composite aerogels are achieved by incorporating the 2D M-tetrahydroxy-1,4-quinone (M-THQ) (M = Cu, Cu/Co, or Cu/Ni) into CNTs@rGO aerogel electrodes using a 3D-printing direct ink writing (DIW) technique. Benefiting from the high capacity of M-THQ and abundant porosity of the 3D-printed microlattice electrodes, an excellent capacitive performance of the M-THQ@CNTs@rGO cathodes is achieved based on the fast electron/ion transport. Furthermore, the 3D-printed lithium-ion hybrid supercapacitor (LIHCs) device assembled with Cu/Co-THQ@CNTs@rGO cathode and C60@VNNWs@rGO anode delivers a remarkable electrochemical performance. More importantly, this work manifests the practicability of printing 2D CMOFs electrodes, which provides a substantial research basis for 3D printing energy storage.

9.
Nanomaterials (Basel) ; 11(4)2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33917057

RESUMO

Fabrication of polymer composite fibers embedding ultra-long micro/nanowires via an iterative melt co-drawing and bundling technique is reported in this study. The poly(methyl methacrylate) (PMMA) porous array templates were prepared with section-cutting the PMMA/polystyrene (PS) (shell/core) composite fibers and dissolution of inner PS. The results showed that the PS cores or pores in the PMMA matrix are regularly arranged with hexagonal, and their diameter and spacing exhibits a uniform distribution. Especially, the core diameter can be precisely controlled from millimeter-scale to nanometer-scale by multi-step melt co-drawing. Based on the PMMA porous array templates, the Cu nanowires were successfully prepared by electrochemical deposition. Moreover, to fabricate PMMA ultra-long micro/nanowires, the composite fibers with converse shell/core component of PS/PMMA were initially prepared, and then the outer PS was dissolved. The obtained PMMA micro/nanowires were characterized with smooth complete orientation structure. The study provides an experimental basis for fabricating such polymer composite fibers, micro/nano porous array templates, and micro/nanowires with precise and controllable manner to meet the real application requirements.

10.
RSC Adv ; 11(47): 29323-29332, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35479536

RESUMO

The optical performance of fused silica optics used in high-power lasers is known to depend not only on their surface damage resistance, but also on their surface quality. Previous studies have shown that good fused silica damage performance and surface quality can be achieved by the use of reactive ion etching (RIE), followed by HF-based wet shallow etching (3 µm). In this study, two kinds of HF-based etchants (aqueous HF and HF/NH4F solutions) were employed to investigate the effect of HF-based etching on the optical performance of reactive-ion-etched fused silica surfaces at various HF-based shallow etching depths. The results showed that the addition of NH4F to HF solution makes it possible to produce a high-quality optical surface with a high laser-induced damage threshold, which is strongly associated with the surface roughness and fluorescence defect density. Additionally, changing the HF-based etching depth over the range from 1 µm to 3 µm can affect the surface damage resistance and absorption performance of RIE-treated fused silica. The light-scattering results indicate that the point defect density plays an important role in the determination of the HF-based etching depth. Understanding these trends can enable the advantages of the combined technique of RIE and HF-based etching during the fabrication of high-quality fused silica optics.

11.
Animals (Basel) ; 10(9)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32846893

RESUMO

Coccidiosis is one of the most economically important diseases affecting the poultry industry. Currently, anticoccidial drugs used in veterinary clinics show many deficiencies, and new control measures are urgently needed. This study presents an anticoccidial herbal powder "Shi Yin Zi", which consists of Cnidium monnieri (L.) Cuss, Taraxacum mongolicum Hand.-Mazz., and sodium chloride. In chickens infected with Eimeria tenella, supplementation with "Shi Yin Zi" powder for 3 d prior to infection or treatment with "Shi Yin Zi" powder after infection could improve the survival rate and relative growth rate and alleviate the pathological changes in the cecum, liver, and kidney. "Shi Yin Zi" powder could recover the levels of alanine aminotransferase, creatinine, albumin, and triglycerides in serum. The hemorrhage occurrence and total number of oocysts in feces were reduced. The anti-coccidial indexes reached 165 for the prophylactic effect and 144 for the therapeutic effect. The anti-coccidial effects were equal to positive controls (monensin and sulfamlopyrazine). These results suggest that "Shi Ying Zi" powder possesses a potent anticoccidial effect and exhibits the potential to control E. tenella infection.

12.
Nanomaterials (Basel) ; 9(4)2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30970558

RESUMO

The simple yet efficient and versatile fabrication of colloidal crystals was investigated based on the solidification-induced colloidal crystallization process with particle/water suspension as precursor. The resulting colloidal crystals were constituted by crystal grains with sizes ranging from several tens of micrometers to a few millimeters. Each of the grains had a close-hexagonal array of colloids, which endowed the bulk colloidal crystal powders with some specific optical properties. The freezing of water was shown as the major driving force to form colloidal crystal grains, which supersaturated the solution with nanoparticles and thus induced the formation and growth of colloidal crystal seeds. This process is intrinsically different from those conventional methods based on shearing force, surface tension, columbic interaction or magnetic interaction, revealing a new strategy to fabricate colloidal crystals in a convenient and efficient way.

13.
Opt Express ; 27(3): 2268-2280, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732266

RESUMO

Buffered HF-based etching can effectively improve the laser damage resistance of the fused silica, but deep etching would cause the deteriorations in surface roughness and hardness, and decrease the laser-induced damage threshold. Capping a glass thin layer on the etched surface via plasma chemical vapor deposition in one step could overcome those deteriorations. We found that the deposition of the glass thin layer can further reduce the impurity element contamination and the PL intensity while retaining the low subsurface defect density as well as for the deeply etched sample. The surface quality, surface hardness and the laser damage resistance of the fused silica can be significantly improved by the glass thin layer, which reveals the potential application in high power laser facility.

14.
Opt Lett ; 43(20): 4969-4972, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30320796

RESUMO

Fluorinated ethylene propylene (FEP) film is an attractive candidate for mitigating target debris in high-power laser systems due to its remarkable advantages such as low cost, low absorption, and high damage threshold. However, the inert surface with bad wettability presents an enormous challenge to realize optical antireflection. In this Letter, we experimentally demonstrate that broadband antireflection of FEP film can be achieved through combining oxygen plasma treatment and solgel coating techniques. By optimizing the plasma treating time and withdrawal rate during the coating process, the treated FEP film has 4.7% enhanced transmittance compared to the untreated sample. In this case, transmittance over 99% with wide wave bands ranging from 600 to 950 nm is achieved. The mechanism of broadband antireflection was revealed by investigating the fluorocarbon groups on the FEP surface. The applicable wave band of antireflective FEP film can be designed at will by changing plasma-treating conditions, which could open up a new avenue in the field of laser debris mitigation.

15.
Opt Lett ; 43(20): 5017-5020, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30320808

RESUMO

We demonstrate superconducting nanowire single-photon detectors (SNSPDs) based on a fractal design of the nanowires to reduce the polarization sensitivity of detection efficiency. We patterned niobium titanium nitride thin films into Peano curves with a linewidth of 100 nm and integrated the nanowires with optical microcavities to enhance their optical absorption. At a base temperature of 2.6 K, the fractal SNSPD exhibited a polarization-maximum device efficiency of 67% and a polarization-minimum device efficiency of 61% at a wavelength of 1550 nm. Therefore, the polarization sensitivity, defined as their ratio, was 1.1, lower than the polarization sensitivity of the SNSPDs in the meander design. The reduced polarization sensitivity of the detector could be maintained for higher-order spatial modes in multimode optical fibers and could tolerate misalignment between the optical mode and the detector. This fractal design is applicable to both amorphous and polycrystalline materials that are commonly used for making SNSPDs.

16.
Opt Express ; 26(15): 19707-19717, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30114140

RESUMO

A facile method was proposed to enhance the laser damage performance of the fused silica optics by coating a PVA film on the rear surface of the optics. FDTD simulation result suggests that the PVA coating with suitable thickness can transfer the maximal electric field intensity from the rear surface to the interface between the coating and air, and reduce the electric field intensity of the rear surface remarkably. LIDT tests reveal that the LIDT of fused silica with PVA coating changed periodically with respect to the coating thickness, which agrees well with the tendency predicted by FDTD simulation. Finally, PVA coatings with a thickness of 60 nm and 300 nm can both improve the LIDT of AMP-treated fused silica by ~20%, which provide a potential to be applied in high power laser facility.

17.
Molecules ; 23(7)2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-30037030

RESUMO

Based on previous studies about microflora regulation and immunity enhancement activities of polysaccharides from Codonopsis pilosula Nannf. var. modesta (Nannf.) L. T. Shen (CPP), there is little study on intestinal mucosal immunity, which is a possible medium for contacting microflora and immunity. In the present study, the BALB/c mice were divided into five groups (eight mice in each group), including a normal group (Con), a model control group (Model), and model groups that were administered CPP (50, 100, 200 mg/kg/d) orally each day for seven days after intraperitoneal injection of 60 mg/kg BW/d cyclophosphamide (CP) for three days. CPP recovered the spleen index and restored the levels of IFN-γ, IL-2, IL-10, as well as serum IgG. In addition, it elevated ileum secretory immunoglobulin A (sIgA), the number of Lactobacillus and acetic acid content in cecum. These results indicated that CPP plays an important role in the protection against immunosuppression, especially mucosa immune damage, and the inhibition of pathogenic bacteria colonization, which could be considered a potential natural source of immunoregulator.


Assuntos
Codonopsis/química , Ciclofosfamida/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Imunidade/efeitos dos fármacos , Hospedeiro Imunocomprometido , Fatores Imunológicos/farmacologia , Imunossupressores/farmacologia , Polissacarídeos/farmacologia , Animais , Citocinas/sangue , Imunidade nas Mucosas/efeitos dos fármacos , Imunoglobulina A Secretora/sangue , Imunoglobulina A Secretora/imunologia , Fígado/efeitos dos fármacos , Fígado/imunologia , Camundongos , Baço/efeitos dos fármacos , Baço/imunologia , Timo/efeitos dos fármacos , Timo/imunologia
18.
PLoS One ; 13(2): e0192692, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29466421

RESUMO

Rotavirus (RV), belonging to Reoviridae family, is the leading cause of acute severe viral diarrhea in children (under 5 years old) and infant animals worldwide. Although vaccines are commonly used to prevent infection, episodes of diarrhea caused by RV frequently occur. Thus, this study was conducted to determine whether resveratrol had protective effects against RV infection in piglets. Following pretreatment with resveratrol dry suspension through adding into the basal diet for 3 weeks, the piglets were orally challenged with RV. We found that resveratrol could alleviate diarrhea induced by RV infection. Resveratrol-treatment inhibited the TNF-α production, indicating that the anti-RV activity of resveratrol may be achieved by reducing the inflammatory response. The IFN-γ level was elevated in 10mg/kg/d resveratrol-treated group and 30mg/kg/d resveratrol-treated group after RV infection. The ratios of CD4+/CD8+ in resveratrol-treated groups were the same as that in mock infected group, suggesting that resveratrol could maintain the immune function in RV-infected piglets. It was found that resveratrol could alleviate diarrhea induced by RV infection. These results revealed that resveratrol dry suspension could be a new control measure for RV infection.


Assuntos
Diarreia/veterinária , Infecções por Rotavirus/veterinária , Estilbenos/administração & dosagem , Doenças dos Suínos/imunologia , Animais , Citocinas/sangue , Diarreia/imunologia , Diarreia/prevenção & controle , Estresse Oxidativo , Resveratrol , Infecções por Rotavirus/imunologia , Infecções por Rotavirus/prevenção & controle , Suínos , Doenças dos Suínos/prevenção & controle , Subpopulações de Linfócitos T
19.
Artigo em Inglês | MEDLINE | ID: mdl-29483932

RESUMO

Resveratrol, a polyphenolic plant antitoxin, has a wide range of pharmacological activities. In this study, we systematically evaluated the effects of resveratrol dry suspension (RDS) on immune function in piglets that were treated with different doses of RDS for 2 weeks. The results showed that the RDS has significant effects on the development, maturation, proliferation, and transformation of T lymphocytes. RDS could regulate humoral immune responses by upregulating the release of IFN-γ and downregulating the release of TNF-α. After piglets were vaccinated against classical swine fever virus and foot-and-mouth disease virus, the antibody titers were significantly increased. RDS treatment showed an excellent resistance to enhance T-SOD activity. Values of blood routine and blood biochemistry showed no toxicity. These results suggested that RDS could be considered as an adjuvant to enhance immune responses to vaccines, as well as dietary additives for animals to enhance humoral and cellular immunity.

20.
ACS Appl Mater Interfaces ; 9(6): 5430-5436, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28098973

RESUMO

In this paper, a facilely prepared electrochemiluminescence (ECL) biosensor was developed for Escherichia coli O157:H7 quantitative detection based on a polydopamine (PDA) surface imprinted polymer (SIP) and nitrogen-doped graphene quantum dots (N-GQDs). N-GQDs with a high quantum yield of 43.2% were synthesized. The uniform PDA SIP film for E. coli O157:H7 was established successfully with a facile route. The dopamine and target bacteria were electropolymerized directly on the electrode. After removal of the E. coli O157:H7 template, the established PDA SIP can selectively recognize E. coli O157:H7. Accordingly, E. coli O157:H7 polyclonal antibody (pAb) was labeled with N-GQDs. The bioconjugation of SIP-E. coli O157:H7/pAb-N-GQDs can generate intensive ECL irradiation with K2S2O8. As a result, E. coli O157:H7 was detected with the ECL sensing system. Under optimal conditions, the linear relationships between the ECL intensity and E. coli O157:H7 concentration were obtained from 101 colony-forming units (CFU) mL-1 to 107 CFU mL-1 with a limit of detection of 8 CFU mL-1. The biosensor based on this SIP film was applied in water sample detection successfully. The N-GQD-based ECL analytical method for E. coli O157:H7 was reported for the first time. The sensing system had high selectivity to the target analyte, provided new opportunities for use, and increased the rate of disease diagnosis and treatment and the prevention of pathogens.


Assuntos
Técnicas Biossensoriais , Escherichia coli O157 , Indóis , Impressão Molecular , Polímeros
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