Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
J Inflamm Res ; 17: 7081-7097, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39380664

RESUMO

Purpose: Acute liver injury (ALI) is characterized by inflammation and oxidative stress (OS). Although mangiferin (MGF) has antioxidant and anti-inflammatory effects, its role in ALI remains unclear. Accordingly, we investigated the MGF molecular mechanism in carbon tetrachloride (CCl4)-induced ALI in vivo and in vitro. Materials and Methods: The CCl4 was utilized to induce ALI in mice. In vivo, the therapeutic effects of MGF on CCl4-induced liver injury were evaluated through biochemical assays and histomorphological analysis. Additionally, immunohistochemistry, immunofluorescence, ELISA and Western blotting were further applied to explore the mechanism. In vitro, The CCK-8 assay and flow cytometry were employed to investigate the protective effects of MGF against CCl4-induced toxicity in HepG2 cells, while mitochondrial reactive oxygen species levels and Western blotting were used to explore the biological effects and molecular mechanisms. Results: MGF treatment resulted in a reduction in serum levels of AST and ALT, diminished concentrations of TNF-α, IL-6, and IL-1ß in liver tissue, and concurrently decreased cellular apoptosis. Furthermore, MGF pretreatment enhanced the activity of SOD and GSH while concurrently diminishing the MDA production. This study further demonstrated the upregulation of Nrf2, NQO1, and HO-1 protein expression levels, as well as the downregulation of p-p65 protein expression levels. In vitro investigations revealed that the mitigation of CCl4-induced inflammation and OS by MGF was mediated via the Nrf2- antioxidant response element (ARE) pathway, which was disrupted by ML385 in HepG2 cells. Conclusion: CCl4 can induce liver injury, while treatment with MGF mitigates ALI by inhibiting oxidative stress, inflammation, and apoptosis. The protective mechanism of MGF is mediated by the Nrf2-ARE pathway activation.

2.
ACS Infect Dis ; 10(10): 3516-3527, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39283729

RESUMO

Fungal keratitis (FK) is a blinding corneal infectious disease. The prognosis is frequently unfavorable due to fungal invasion and an excessive host inflammatory response. Licochalcone A (Lico A) exhibits a broad spectrum of pharmacological activities, encompassing antifungal, anti-inflammatory, antioxidation, and antitumor properties. However, the role of Lico A has not yet been studied in FK. In this study, we discovered that Lico A could disrupt Aspergillus fumigatus (A. fumigatus) biofilms, inhibit fungal growth and adhesion to host cells, induce alterations of hyphal morphology, and impair the cell membrane and cell wall integrity and mitochondrial structure of A. fumigatus. Lico A can alleviate the severity of FK in mice, reduce neutrophil infiltration and fungal load, and significantly decrease the pro-inflammatory cytokines in mouse corneas infected with A. fumigatus. In vitro, we also demonstrated that Lico A increased the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) around the nucleus in human corneal epithelial cells (HCECs) stimulated with A. fumigatus. We verified that the anti-inflammatory effect of Lico A is associated with the activation of the Nrf2/HO-1 axis. These results indicated that Lico A could provide a protective role in A. fumigatus keratitis through its anti-inflammatory and antifungal activities.


Assuntos
Antifúngicos , Aspergilose , Aspergillus fumigatus , Chalconas , Heme Oxigenase-1 , Ceratite , Fator 2 Relacionado a NF-E2 , Transdução de Sinais , Aspergillus fumigatus/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Animais , Ceratite/tratamento farmacológico , Ceratite/microbiologia , Camundongos , Transdução de Sinais/efeitos dos fármacos , Humanos , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/genética , Chalconas/farmacologia , Chalconas/química , Antifúngicos/farmacologia , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Modelos Animais de Doenças , Córnea/microbiologia , Córnea/efeitos dos fármacos , Feminino , Citocinas/metabolismo
3.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(4): 490-496, 2024 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-39223013

RESUMO

Objective To investigate the status and influencing factors of pressuring feeding style among caregivers in remote rural areas of Sichuan province. Methods Multistage sampling was conducted to select infants of 6-11 months old who had received complementary food and their caregivers in remote rural areas of Sichuan province.A questionnaire was used to collect sociodemographic characteristics of infants and their caregivers,pressuring feeding behaviors,feeding environment,and caregivers' negative emotions.Quantile regression was employed to analyze the factors influencing pressuring feeding among caregivers of infants. Results A total of 1358 pairs of infants and their caregivers were included,with the pressuring feeding behavior score of 11 (8,14).Parity was the protective factor for caregivers' pressuring feeding (ß25=-1.17,P<0.001;ß50=-1.40,P=0.002;ß75=-2.18,P<0.001).Whether infants played with toys while eating (ß25=1.00,P<0.001;ß50=1.20,P=0.003;ß75=1.42,P<0.001) and whether infants watched TV/mobile phones (ß25=0.50,P=0.048;ß50=1.07,P=0.004) were the risk factors.At the 75th percentile,caregivers' negative emotions were the risk factor for pressuring feeding (ß75=0.94,P=0.015).Caregivers' education background (ß25=0.83,P=0.034;ß50=0.87,P=0.021) and family income (ß75=1.09,P=0.012) were also significantly associated with pressuring feeding scores at different quartile points. Conclusion Pressuring feeding behaviors of caregivers in remote rural areas of Sichuan province need to be improved.Based on the characteristics of infants and their families,guidance should be carried out to improve the feeding environment and the mental health of caregivers,thereby promoting reasonable feeding behaviors among caregivers of infants in rural areas.


Assuntos
Cuidadores , Comportamento Alimentar , População Rural , Humanos , Lactente , Cuidadores/psicologia , Feminino , China , Masculino , Inquéritos e Questionários , Adulto
4.
Anal Chim Acta ; 1316: 342875, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-38969433

RESUMO

BACKGROUND: Indole-3-acetic acid (IAA) and salicylic acid (SA), pivotal regulators in plant growth, are integral to a variety of plant physiological activities. The ongoing and simultaneous monitoring of these hormones in vivo enhances our comprehension of their interactive and regulatory roles. Traditional detection methods, such as liquid chromatography-mass spectrometry, cannot obtain precise and immediate information on IAA and SA due to the complexity of sample processing. In contrast, the electrochemical detection method offers high sensitivity, rapid response times, and compactness, making it well-suited for in vivo or real-time detection applications. RESULTS: A microneedle electrochemical sensor system crafted from disposable stainless steel (SS) wire was specifically designed for the real-time assessment of IAA and SA in plant in situ. This sensor system included a SS wire (100 µm diameter) coated with carbon cement and multi-walled carbon nanotubes, a plain platinum wire (100 µm diameter), and an Ag/AgCl wire (100 µm diameter). Differential pulse voltammetry and amperometry were adopted for detecting SA and IAA within the range of 0.1-20 µM, respectively. This sensor was applied to track IAA and SA fluctuations in tomato leaves during PstDC3000 infection, offering continuous data. Observations indicated an uptick in SA levels following infection, while IAA production was suppressed. The newly developed disposable SS wire-based microneedle electrochemical sensor system is economical, suitable for mass production, and inflicts minimal damage during the monitoring of SA and IAA in plant tissues. SIGNIFICANCE: This disposable microneedle electrochemical sensor facilitates in vivo detection of IAA and SA in smaller plant tissues and allows for long-time monitoring of their concentrations, which not only propels research into the regulatory and interaction mechanisms of IAA and SA but also furnishes essential tools for advancing precision agriculture.


Assuntos
Técnicas Eletroquímicas , Ácidos Indolacéticos , Folhas de Planta , Ácido Salicílico , Solanum lycopersicum , Aço Inoxidável , Solanum lycopersicum/química , Ácidos Indolacéticos/análise , Ácido Salicílico/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Aço Inoxidável/química , Técnicas Eletroquímicas/instrumentação , Agulhas , Doenças das Plantas/microbiologia
5.
Ultrasonics ; 141: 107344, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38772060

RESUMO

Ultrasonic microneedle patches, a class of ultrasound-driven transdermal drug delivery systems, are promising in addressing bacterial biofilms. This device has been proven to be more effective in treating Staphylococcus aureus biofilms than drug in free solution. However, there exists a notable gap in understanding how various excitation conditions and material parameters affect drug delivery efficiency. This study aims to fill this void by conducting an comprehensive multi-physics numerical analysis of ultrasonic microneedle patches, with the ultimate goal of enhancing drug delivery. First, we investigate the impact of various ultrasound frequencies on drug penetration depths. The findings reveal that local resonance can accelerate drug release within a shorter time window (first 1.5 h), whereas non-resonant frequencies enable more profound and prolonged diffusion. This information is crucial for medical professionals in selecting the most effective frequency for optimal drug administration. Furthermore, our investigation extends to the effects of applied voltage on temperature distribution, a critical aspect for ensuring medical safety during the application of these patches. Additionally, we examine how particles of different sizes respond to acoustic pressure and streaming fields, providing valuable insights for tailoring drug delivery strategies to specific therapeutic needs. Overall, our findings offer comprehensive guidelines for the effective use of ultrasonic microneedle patches, potentially shifting the paradigm in patient care and enhancing the overall quality of life.


Assuntos
Biofilmes , Sistemas de Liberação de Medicamentos , Agulhas , Staphylococcus aureus , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Staphylococcus aureus/fisiologia , Ondas Ultrassônicas , Antibacterianos/administração & dosagem , Administração Cutânea
6.
Nanotheranostics ; 8(1): 100-111, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38164502

RESUMO

Background: Phthalocyanine (PC) and naphthalocyanine (NC) dyes have long garnered interest as theranostic agents for optical imaging and phototherapy due to their near-infrared absorbance, photostability, imaging contrast, and proven safety in clinical trials. Yet, only a small fraction of these dyes has been evaluated as photothermal therapy (PTT) agents for cancer treatment. Methods: Nearly 40 distinct NC and PC dyes were encapsulated within polymeric PEG-PCL micelles via oil-in-water emulsions. The optimal NC/PC-loaded micelle formulations for PTT and photoacoustic (PA) imaging were identified through in vivo and in vitro studies. Results: The most promising candidate, CuNC(Octa)-loaded micelles, demonstrated a strong PA signal with a peak absorbance at ~870 nm, high photothermal efficiency, and photostability. The CuNC(Octa)-loaded micelles exhibited heat generation as good or better than gold nanorods/nanoshells and >10-fold higher photoacoustic signals. Micelle preparation was reproducible/scalable, and the CuNC(Octa)-loaded micelles are highly stable under physiological conditions. The CuNC(Octa)-loaded micelles localize within tumors via enhanced permeability and retention and are readily detectable by PA imaging. In a syngeneic murine tumor model of triple-negative breast cancer, CuNC(Octa)-loaded micelles demonstrate efficient heat generation with PTT, leading to the complete eradication of tumors. Conclusions: CuNC(Octa)-loaded micelles represent a promising theranostic agent for PA imaging and PTT. The ability to utilize conventional ultrasound in combination with PA imaging enables the simultaneous acquisition of information about tumor morphology and micelle accumulation. PTT with CuNC(Octa)-loaded micelles can lead to the complete eradication of highly invasive tumors.


Assuntos
Nanopartículas , Neoplasias , Técnicas Fotoacústicas , Animais , Camundongos , Micelas , Terapia Fototérmica , Medicina de Precisão , Técnicas Fotoacústicas/métodos , Nanopartículas/uso terapêutico , Indóis , Corantes/uso terapêutico , Neoplasias/terapia , Neoplasias/tratamento farmacológico
7.
Artigo em Inglês | MEDLINE | ID: mdl-37931977

RESUMO

OBJECTIVE: Assess whether local health facilities can adequately support the performance of general practitioners (GPs) trained by China's national compulsory services programme (CSP). DESIGN: Prospective cohort study. SETTING: Health facilities in middle and western rural areas in China, 2015-2022. PARTICIPANTS: Cohorts of CSP graduates from 2015 to 2019 in four major medical universities. MAIN OUTCOMES: Job performance measured by a 12-item Job Performance Scale; productivity measured by outpatient volume per day; turnover measured by ever changing jobs within the past year. RESULTS: 91.2%, 92.0% and 90.5% GPs working in township health centres reported inadequate medication, equipment and external assistance from higher level hospitals, while CSP graduates working in secondary or tertiary hospitals reported a lower rate of less than 60%. The top three tests reported as lacking were blood gases (67.7%), microbiology (61.6%) and cancer biomarkers (49.7%); the top three lacked procedures were CT scan (64.8%), MRI scan (58.1%) and ambulatory BP monitoring (55.8%); and the top three lacked drugs were drugs for cardiovascular diseases (23.3%), systematic hormonal preparations (17.7%) and traditional Chinese medicines (13.0%). Multivariable analysis showed that facility support was positively associated with job performance-adequate medication increased job performance by 2.2 points (95% CI 0.7 to 3.8), and adequate external assistance increased job performance by 3.3 points (95% CI 1.8 to 4.8). Facility support was also positively associated with productivity-adequate medication increased outpatients seen per day by 20% (95% CI 0.1 to 0.3), and adequate equipment increased outpatients seen per day by 12% (95% CI 0.0 to 0.2). Facility support did not have significant impact on turnover, but GPs who changed jobs in the past year were 1.9-2.3 times more likely to report adequate facility support. CONCLUSION: GPs in township health centres experienced a high prevalence of shortage in facility support. The identification of a positive association between facility support and performance and productivity has implications for future research and resources deployment in primary healthcare.


Assuntos
Clínicos Gerais , Humanos , Estudos Prospectivos , Recursos Humanos , Atenção Primária à Saúde , China
8.
Dalton Trans ; 52(47): 17792-17796, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37969004

RESUMO

Hard-Soft Acid-Base (HSAB) principle plays an important guiding role in the design and synthesis of novel clusters and coordination compounds, in which "soft acids prefer to react with soft bases, while hard acids have an affinity for hard bases". Based on HSAB principle, four Ag/Ti heterometallic clusters, including Ag2Ti10, Ag2Ti11 with "Ti-encapsulated Ag" configurations, and two "Ag-encapsulated Ti" structures Ag2Ti2 and Ag2Ti12, were synthesized under solvothermal conditions. In addition, Ag2Ti12 exhibited an efficient and stable catalytic activity for sulfide oxidation. This work provides not only a new structural model for the modulation of the catalytic oxidative desulfurization properties of Ag/Ti heterometallic clusters but also a new insight of the utilization of phosphine-containing ligands to regulate the structure of Ag/Ti heterometallic clusters.

9.
J Phys Chem Lett ; 14(43): 9665-9676, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37870971

RESUMO

The emerging nitrogen-embedded multiple resonance (MR) emitters with an indolo[3,2,1-jk] carbazole (ICz) unit have exhibited promising performance for high-resolution organic light-emitting diode (OLED) devices, while the underlying photophysics has been rarely reported. In this work, the optical spectra, color purity, and emitting efficiency of ICz-based MR emitters were investigated by using electronic structure and thermal vibration correlation function (TVCF) calculations. Unlike B-N MR emitters, the high color purity of investigated ICz-based MR emitters was mainly contributed by considerable structural rigidity, which also greatly affects the radiative decay rate and fluorescence quantum yield of the S1 state. For the majority of investigated emitters, potential reverse intersystem crossing (RISC) channels (T1 → S1 and T2 → S1) are limited by thermally inaccessible ΔEST* or insufficient spin-orbital coupling (SOC), which can be distinguished by the calculated temperature-dependent RISC rate pattern. We provided a systematic photophysical picture for ICz-based MR emitters that might be interesting for the OLED design and application community.

10.
Water Sci Technol ; 87(9): 2159-2171, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37186621

RESUMO

Six polycyclic aromatic hydrocarbons (PAHs) including naphthalene (Nap), fluorene (Flu), phenanthrene (Phe), fluoranthene (Fla), pyrene (Pyr), and chrysene (Chr) were detected in runoff from five athletic fields during three rainfall events. The event mean concentration (EMC) of ∑6PAHs ranged from 3.96 to 23.23 µg/L, which was much higher than the EMC in urban traffic area runoff. Except for Nap, the PAH concentrations followed in the order of artificial turf > badminton court > basketball court > plastic runway > optennis court. The surface characteristics of the athletic fields, such as the composition of materials and roughness, played an essential role in the release of PAHs. ∑6PAHs concentration during the 2nd rainfall event (July 22nd) was the highest among the three rainfall events, indicating that high rainfall intensity facilitated the PAHs release. PAHs during three rainfall events showed little first flush effect except for the artificial turf during the 2nd (22nd July) and 3rd (29th July) rainfall events. The first flush effect could be affected by rainfall characters, PAH properties, and surface characteristics of athletic fields. Ecological risk assessment showed that PAHs in runoff corresponded to moderate-to-high risk, while health risk assessment showed that PAHs could pose a potential carcinogenic danger to human health via dermal contact.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Esportes , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental , Medição de Risco , China
11.
Anal Bioanal Chem ; 414(26): 7721-7730, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36068347

RESUMO

The detection of phytohormones in real time has attracted increasing attention because of their critical roles in regulating the development and signaling of plants, especially in defense against biotic stresses. Herein, stainless steel sheet electrodes modified with carbon cement were coupled with paper-based analysis devices for direct and simultaneous detection of salicylic acid (SA) and indole-3-acetic acid (IAA) in plants. We demonstrated that the excellent conductivity of stainless steel sheet electrodes enabled us to simultaneously differentiate IAA and SA at a level of 10 nM. With our approach, the content of IAA and SA in Arabidopsis thaliana leaves infected or not infected with Pst DC3000 could be rapidly quantified at the same time. Our experimental results on differentiation of IAA and SA at different time points showed that there were antagonistic interactions between the IAA and SA after infection of Arabidopsis leaves with Pst DC3000. By offering a cost-effective approach for rapid and sensitive detection of IAA and SA, this study suggests that electrochemical detection can be used in the study and development of precision agriculture technology.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácido Salicílico/farmacologia , Aço Inoxidável , Reguladores de Crescimento de Plantas , Proteínas de Arabidopsis/farmacologia , Pseudomonas syringae/fisiologia , Ácidos Indolacéticos , Eletrodos , Estresse Fisiológico , Carbono/farmacologia , Doenças das Plantas
12.
J Phys Chem Lett ; 13(29): 6664-6673, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35839081

RESUMO

Delayed fluorescence (DF) emitters with high color purity are of high interest for applications in high-resolution displays. However, the charge transfer required by high emitting efficiency usually conflicts with the expected color purity. In this work, we investigated the S1/S0 conformational relaxation, spin-orbital coupling (SOC), and vibronic coupling of hot-exciton emitters while hybrid local and charge transfer (HLCT) state tuning was achieved by a structural meta-effect. The meta-linkage leads to suppressed S1/S0 conformational relaxation and weakened vibronic coupling, while the unsacrificed emitting efficiency is largely ensured by multiple rISC channels (Tn → Sm) with thermally accessible triplet-singlet energy gap (ΔEST) and effective SOC. We demonstrated that the unique excited-state mechanism provides opportunities to improve the emitting color purity of hot-exciton emitters without sacrificing emitting efficiency by HLCT state tuning with simple chemical structural modification, for which hot-exciton emitters might play a more important role for high-resolution organic light-emitting diode displays.


Assuntos
Fluorescência
13.
Ultrasonics ; 119: 106627, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34688981

RESUMO

This article reports a new mechanism involving a non-perforated resonant elastic metamaterial to achieve the complete conversion of Lamb waves (A0 and S0) into the fundamental shear horizontal (SH0) wave. The proposed metamaterial ultrasound mode convertor is studied via the observation of the special resonant shear motion of its unit cells, initiating with a conventional additive stub design. Thereafter, such a stubbed structure is further modified to fully couple the Lamb modes with the shear horizontal stub motion. By investigating the band structure of the metamaterial unit cell through modal analysis and tuning the shear resonant motions, a complete SH0 mode generation band within the simultaneous Lamb modes bandgap can be established in a wide frequency range. Such a special bandgap situation enables the complete mode conversion from Lamb waves into shear horizontal waves. The transformation capability of the proposed ultrasound mode convertor is further substantiated via the harmonic analysis of metamaterial chain model, showcasing the frequency spectrum of the transmitted wave modes. The optimal configuration is determined by conducting a parametric study to identify the most effective mode conversion performance. Finally, a coupled-field transient finite element simulation is carried out to acquire the dynamic response of the structure. The frequency-wavenumber analysis of the transmitted wave field illuminates the successful realization of the mode conversion behavior. Experimental demonstrations are presented to validate the numerical predictions. The proposed complete mode conversion capability may possess great potential for wave control and manipulation.

14.
J Hazard Mater ; 416: 125897, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492835

RESUMO

Interconnected macro-porous cryogels with robust and pore-tunable structures have been fabricated using chemically crosslinked microfibrillated cellulose (MFC). Periodate oxidation was initially conducted to introduce aldehyde groups into the MFC surface, followed by the freeze-induced chemical crosslinking via the formation of hemiacetal bonds between aldehyde and hydroxyl at -12 °C. The cryogels with pore-tunable structures and sharply enhanced mechanical strengths were finally achieved by re-assembly of MFCs through soaking in NaIO4 solution. Furthermore, the MFC cryogels were post-crosslinked by polyethyleneimine (PEI), bestowing the cryogels with the capability of adsorbing anionic dyes. The stress of the PEI-MFC cryogel at the 80% strain was determined to be 304.5 kPa, which is the maximum value for the nanocellulose-based cryogels reported so far. Finally, the adsorption performances of PEI-MFC cryogels for methyl orange (MO) were evaluated. Maximum adsorption capacity of 500 mg/g could be obtained by the Langmuir model, outperforming that of previous absorbent materials. Reuse experiments indicated that over 90% of adsorption capacity was retained after 6 cycles. Continuous clean-up experiments demonstrated excellent MO removal abilities of the PEI-MFC cryogel. This study shows that the novel, green strategy to fabricate the robust cryogel extends the practical applications of nanocellulose adsorbents for environmental remediation.


Assuntos
Criogéis , Nanofibras , Adsorção , Compostos Azo , Celulose , Corantes , Porosidade
15.
Carbohydr Polym ; 272: 118498, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34420751

RESUMO

Construction of monolithic cryogels that can efficiently adsorb proteins is of great significance in biotechnological and pharmaceutical industries. Herein, a novel approach is presented to fabricate microfibrillated cellulose (MFC)/sodium alginate (SA) cryogels by using freezing-induced oxa-Michael reaction at -12 °C. Thanks to the controllable reactiveness of divinyl sulfone (DVS), cryo-concentrated pH increase activates the oxa-Michael reaction between DVS and hydroxyl groups of MFCs and SAs. The obtained composite cryogel exhibits outstanding underwater shape recovery and excellent fatigue resistance. Moreover, the MFC/SAs reveal a high lysozyme adsorption capacity of 294.12 mg/g, surpassing most of absorbent materials previously reported. Furthermore, the cryogel-packed column can purify lysozyme continuously from chicken egg white, highlighting its outstanding practical application performance. Reuse experiments indicated that over 90% of lysozyme extraction capacity was retained after 6 cycles. This work provides a new avenue to design and develop next-generation chromatographic media of natural polysaccharide-based cryogel for protein purification.


Assuntos
Criogéis , Nanofibras , Alginatos , Celulose , Congelamento
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 262: 120092, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34175758

RESUMO

Recently, it is urgent to ameliorate the accumulation and quantification performances of surface-enhanced Raman scattering-based lateral flow immunoassay (SERS-based LFIA) to promote its reliable clinical application. Herein, a smart hydrophilic-hydrophobic SERS-based LFIA strip was demonstrated by decorating Ag nanoplates with hydrophilic surface onto the specific regions of hydrophobic polymethylmethacrylate (PMMA) film with Raman internal standard (IS), which can unexpectedly inhibit the "coffee-ring phenomenon". The target analytes were consequently enriched in the SERS-active Ag regions by the hydrophobic PMMA, considerably endowing the strip with amended quantitative monitoring ability. Aided by immunoprobes of flower-shaped Ag nanoplates, a limit of detection as 10 pg/mL and an outstanding correlation coefficient value (R2) of 0.992 for carcinoembryonic antigen (CEA) were obtained by utilizing this SERS-based LFIA strip, which can be conducive to clinical monitoring and will broaden the field of vision for the point-of-care diagnostic technique.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Ouro , Imunoensaio , Limite de Detecção , Polimetil Metacrilato , Prata
17.
J Agric Food Chem ; 69(6): 1975-1983, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33544589

RESUMO

Surface-enhanced Raman scattering (SERS) with fast and intuitive property has been extensively utilized in the field of food safety. Here, we demonstrated a novel noble metal-polymer hybrid film as a SERS substrate for food fungicide analysis. Benefiting from its transparency and flexibility, poly(dimethylsiloxane) (PDMS) film was chosen as a versatile supporting matrix to grow gold nanobushes (Au NBs) through a seed-mediated process. The as-prepared AuNB-PDMS hybrid film performed satisfactorily in testing 4-nitrothiophenol (4NTP) and exhibited an enhancement factor (EF) of 2.56 × 106. Moreover, the high sensitivity and elastic properties make the hybrid film a promising substrate in practical detection. Hence, the in situ sensing of TBZ, carbaryl, and their mixture was finally realized using the developed hybrid film, which exhibited higher sensitivity than that obtained by the swabbing method. This high-performance SERS substrate based on the flexible and transparent AuNB-PDMS hybrid film has great potential applications in the fast in situ monitoring of biochemical molecules.


Assuntos
Ouro , Nanopartículas Metálicas , Polímeros , Análise Espectral Raman
18.
Water Sci Technol ; 83(2): 381-395, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33504702

RESUMO

Coal gangue (CG) as mineral waste was properly treated and applied as the filter media in permeable pavement systems due to its good sorption ability and mechanical strength. Batch experiments show the maximum adsorption capacity of calcined CG to phosphorus could reach 2.63 mg/g. To evaluate the removal effect of typical runoff pollutants including chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP) and ammonia (NH4+-N), the gravel and sand in a traditional pavement system were replaced by CG respectively. The leaching behavior of the four pollutants in CG modified systems is limited and comparable with traditional system, indicating pretreated CG as filler would not cause environmental risk. CG-based pavement systems improved the removal efficiency of the four pollutants especially for TP. The removal mechanisms including interception, adsorption and microorganism degradation. The removal rates of COD, NH4+-N and TN by CG modified and traditional systems decreased with rainfall duration, while it is not obviously changed with rainfall recurrence period and drying period. Overall, the permeable pavement with CG layers that replaced both sand and gravel layers show best removal efficiency of all pollutants investigated especially for TP (>95%). This study provides a new way for CG utilization and gives the reference for the process design of permeable pavement.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Carvão Mineral , Nitrogênio/análise , Fósforo , Chuva , Movimentos da Água , Poluentes Químicos da Água/análise
19.
J Hazard Mater ; 403: 124009, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33265038

RESUMO

Here, straight upward Au nanowires (NWs) were successfully grown onto Fe3O4@TiO2 matrix through a seed-mediated strategy to intensively improve its photocatalysis and SERS performances, facilitating a peculiar recyclable surface-enhanced Raman spectroscopy (SERS)-based immunoassay of CA19-9 in liquid form based on visible light irradiation. Such immunoassay was also supported by a smart heterobifunctional cross-linking agent-mediated probe of anti-CA19-9/4-MBA without metal nanoparticles. A low limit of detection of 5.65 × 10-4 IUmL-1 and a wide linear range from 1000 to 0.001 IUmL-1 were demonstrated through repeated constructing the sandwich immunostructure with only one batch of nanocomposites. Moreover, the actual levels of CA19-9 for colorectal cancer patients were readily measured by the recyclable immunoassay, the results of which are principally consistent with the conventional CLIA detection. Thus, such a green strategy of visible light-induced recyclable immunoassay could be expected to have a potential practicability in the clinical diagnoses of cancer.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Nanofios , Antígeno CA-19-9 , Ouro , Humanos , Imunoensaio , Fenômenos Magnéticos , Semicondutores , Análise Espectral Raman
20.
ACS Appl Mater Interfaces ; 12(12): 14386-14399, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32118398

RESUMO

Pesticides, extensively used in agriculture production, have received enormous attention because of their potential threats to the environment and human health. Hence, in this study, a kind of highly sensitive and stable hybrid surface-enhanced Raman scattering (SERS)-active substrates constructed with flower-like two-dimensional molybdenum sulfide and Ag (MoS2@Ag) has been developed, and then the above substrate was sequentially utilized in the recyclable detection of pesticide residues on several kinds of fruits and vegetables. In the first place, the excellent photocatalytic performance of the MoS2@Ag hybrid substrate was demonstrated, which was attributed to the inhibition of electron-hole combination after the formation of Schottky barrier between the Ag NPs and MoS2 matrix. Thereafter, two calibration curves with ultra-low limits of detection (LOD) as 6.4 × 10-7 and 9.8 × 10-7 mg/mL were established for the standard solutions of thiram (tetramethylthiuram disulfide, TMTD) and methyl parathion (MP), and then the recyclable assay of their single and mixed residues on eggplant, Chinese cabbage, grape, and strawberry was successfully realized. It is interesting to note that the detection recoveries from 95.5 to 63.1% for TMTD and 92.3 to 62.6% for MP are greatly dependent on the size and surface roughness of these foods. In a word, the MoS2@Ag composite matrix shows attractive SERS and photocatalysis performance, and it is expected to have the potential application on food safety monitoring.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas/química , Resíduos de Praguicidas/isolamento & purificação , Praguicidas/isolamento & purificação , Dissulfetos/química , Frutas/química , Limite de Detecção , Molibdênio/química , Resíduos de Praguicidas/química , Resíduos de Praguicidas/toxicidade , Praguicidas/química , Praguicidas/toxicidade , Prata/química , Análise Espectral Raman , Verduras/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA