RESUMO
Human epidermal growth factor receptor 2 (HER2) is one of the specific markers of breast cancer, which is of great significance to the early diagnosis and prognosis of breast cancer. Here, a fluorescence biosensor was established to detect HER2 based on the fluorescence resonance energy transfer (FRET) and photoinduced electron transfer (PET) occurring between the bimetal-polydopamine organic framework with core-shell structure Au@PDA@UiO-66 and the Cy5 fluorophore in HER2-Cy5-Apt. Au@PDA@UiO-66 owns high-efficiency fluorescence quenching ability due to its large specific surface area and strong adsorption of single-stranded DNA. When the target appears, the fluorescence recovery space mediated by the target is large, so the proposed biosensor has better sensitivity in theory. Under optimized conditions, the proposed fluorescent biosensor can detect HER2 in a range of 0.005 ng mL-1 to 15 ng mL-1, with an actual detection limit as low as 0.005 ng mL-1. Corresponding selective experiments, reproducible experiments, and spiked experiments performed well, showing its great potential in HER2 detection.
Assuntos
Técnicas Biossensoriais , Compostos Organometálicos , Humanos , Indóis , Estruturas Metalorgânicas , Ácidos Ftálicos , Polímeros/química , Receptor ErbB-2RESUMO
Microbial degradation of organic compounds is an environmentally benign and energy efficient part in product processing. Fermentation of plant leaves involves enzymatic actions of many microorganisms. However, microbes and enzymes discovered from natural degradation communities were still limited by cultural methods. In this study, we used a metagenomics sequence-guided strategy to identify the microbes and enzymes involved in compound degradation and explore the potential synergy among community members in fermented tobacco leaves. The results showed that contents of protein, starch, pectin, lignin, and cellulose varied in fermented leaves from different growing sites. The different compound contents were closely related to taxonomic composition and functional profiles of foliar microbial communities. Microbial communities showed significant correlations with protein, lignin, and cellulose. Vital species for degradations of protein (Bacillus cereus and Terribacillus aidingensis), lignin (Klebsiella pneumoniae and Pantoea ananatis) and cellulose (Pseudomonas putida and Sphingomonas sp. Leaf20) were identified and relating hydrolytic enzymes were annotated. Further, twenty-two metagenome-assembled genomes (MAGs) were assembled from metagenomes and six potential cellulolytic genomes were used to reconstruct the cellulose-degrading process, revealing the potential metabolic cooperation related to cellulose degradation. Our work should deepen the understanding of microbial roles in plant fermentation and provide a new viewpoint for applying microbial consortia to convert plant organic components to small molecules.
Assuntos
Metagenoma , Metagenômica , Celulose , Lignina , Consórcios Microbianos , Folhas de PlantaRESUMO
We report a low-cost and convenient microchannel resistance (MCR) biosensing platform that uses current signal to report biorecognition. The biorecognition behavior between targets and biometric molecules (antigens, antibodies, or oligonucleotides) immobilized on magnetic beads and polystyrene (PS) microspheres induces a quantitative change in the unreacted PS microspheres. After magnetic separation, the unreacted PS microsphere solution is passed through the microchannel, leading to an obvious blocking effect, resulting in an increase in resistance, which can in turn be measured by monitoring the electric current. Thus, the biorecognition is directly converted into a detectable current signal without any bulky instruments or additional chemical reactions. The MCR biosensing platform is cost-effective and user-friendly with high accuracy. It can be an appropriate analysis technique for point-of-care testing in resource-poor settings.
Assuntos
Técnicas Biossensoriais , Anticorpos , Separação Imunomagnética , Microesferas , PoliestirenosRESUMO
Microgels assembled from bio-based nanomaterials are a promising soft stabilizer for a Pickering system. In this study, nanocellulose microgels with foaming properties were constructed by electrostatic assembly between nisin and 2,2,6,6-tetramethyl piperidine-1-oxyl-oxidized cellulose nanocrystals (TOCNC). Pickering wet foam was prepared by using the microgels as a foaming stabilizer. Nanocellulose microgels exhibited better foaming ability and foam stability than TOCNCs. Quartz crystal microbalance with dissipation and transmission electron microscopy analyses confirmed that the nanocellulose microgels prepared under different nisin concentrations demonstrated significant differences in morphology, conformation, and structural strength. Microgel particles prepared at 0.03 and 0.06 wt % nisin concentrations had a unique dendritic microstructure. Microgels containing 0.06 wt % nisin displayed better foaming ability and foam stability. It was possible that the soft dendritic structure of the microgels could endow bubbles with sufficient thickness and strength to prevent coalescence. This novelty nanocellulose microgel is expected to be used for expanding the application of nanocellulose in the functional interfacial design of Pickering foams.
Assuntos
Microgéis , Nanopartículas , Nanoestruturas , Aerossóis , EmulsõesRESUMO
Organic dye based NIR-II fluorescent probes, owing to their high signal-to-background ratio and deeper penetration, are highly useful for deep-tissue high-contrast imaging in vivo. However, it is still a challenge to design activatable NIR-II fluorescent probes. Here, a novel class of polymethine dyes (NIRII-RTs), with bright (quantum yield up to 2.03 %), stable, and anti-solvent quenching NIR-II emission, together with large Stokes shifts, was designed. Significantly, the novel NIR-II dyes NIRII-RT3 and NIRII-RT4, equipped with a carboxylic acid group, can serve as effective NIR-II platforms for the design of activatable bioimaging probes with high contrast. As a proof of concept, a series of target-activatable NIRII-RT probes (NIRII-RT-pH, NIRII-RT-ATP and NIRII-RT-Hg) for pH, adenosine triphosphate (ATP), and metal-ion detection, were synthesized. By applying the NIRII-RT probe, the real-time monitoring of drug-induced hepatotoxicity was realized.
Assuntos
Meios de Contraste/química , Corantes Fluorescentes/química , Imagem Óptica/métodos , Animais , Vasos Sanguíneos/diagnóstico por imagem , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico por imagem , Verde de Indocianina/química , Linfonodos/diagnóstico por imagem , Camundongos , Polímeros/química , Espectroscopia de Luz Próxima ao InfravermelhoRESUMO
BACKGROUND: Severe hand, foot, and mouth disease (HFMD) is a common childhood illness caused by various enteroviruses. The disease has imposed increased burden on children younger than 5 years old. We aimed to determine the epidemiology, CNS complication, and etiology among severe HFMD patients, in Jiangsu, China. METHODS: Epidemiological, clinical, and laboratory data of severe HFMD cases were extracted from 2009 to 2015. The CNS complication, annually severe illness rates, mortality rates, severity-PICU admission rates, severity-hospitalization rates, and so on were analyzed to assess the disease burden of severe HFMD. All analyses were stratified by time, region, population, CNS involvement and serotypes. The VP1 gene from EV-A71, CV-A16, CV-A6, CV-A10 and other enteroviruses isolates was amplified. Phylogenetic analysis was performed using MEGA5.0. RESULTS: Seven thousand nine hundred ninety-four severe HFMD cases were reported, of them, 7224 cases were inpatients, 611 were PICU inpatients, and 68 were fatal. The average severe illness rate, mortality rate, severity-fatality rate, severity-PICU admission rate, and severity-hospitalization rate were 14.54, 0.12,8506, 76,430, and 903,700 per 1 million, respectively. The severe illness rate was the highest in the 12-23 months age group, and the greatest mortality rate was in the 6-11 months age group. Geographical difference in severe illness rate and mortality were found. Patients infected with EV-A71 were at a higher proportion in different CNS involvement even death. EV-A71, CV-A16 and other enteroviruses accounted for 79.14, 6.49, and 14.47%, respectively. A total of 14 non-EV-A71/ CV-A16 genotypes including CV-A2, CV-A4, CV-A 6, CV-A9, CV-A10, CV-B1, CV-B2, CV-B3, CV-B4, CV-B5, E-6, E-7, E-18, and EV-C96 were identified. Phylogentic analyses demonstrated that EV-A71 strains belonged to subgenotype C4a, while CV-A16 strains belonged to sub-genotype B1a and sub-genotype B1b of genotype B1. CV-A6 strains were assigned to genogroup F, and CV-A10 strains belonged to genogroup D. CONCLUSIONS: Future mitigation policies should take into account the age, region heterogeneities, CNS conditions and serotype of disease. Additional a more rigorous study between the mild and severe HFMD should be warranted to elucidate the difference epidemiology, pathogen spectrum and immunity patterns and to optimize interventions in the following study.
Assuntos
Enterovirus/genética , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/etiologia , Filogenia , Criança , Pré-Escolar , China/epidemiologia , Enterovirus/isolamento & purificação , Enterovirus/patogenicidade , Feminino , Genótipo , Doença de Mão, Pé e Boca/complicações , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Masculino , Mortalidade , Sorogrupo , Proteínas Virais/genéticaRESUMO
Crinkled is associated with embryonic denticle formation and auditory organ development in Drosophila melanogaster. However, the functions of Crinkled have not been fully investigated. Additionally, the genes that participate in the Crinkled pathway are unknown. Phylogenetic analysis indicates that crinkled exhibits a one-to-one orthologous relationship in insects. In Tribolium castaneum, the crinkled gene is 6,498 bp in length and consists of six exons. Crinkled expression peaked during two phases in Tribolium: late embryonic and pupal stages. High levels of crinkled mRNA were detected in the fat body, head, epidermis, ovary, and accessory gland of late adults. Knockdown of crinkled using RNA interference (RNAi) severely affected wing morphogenesis in T. castaneum. We further showed that crinkled silencing reduced forked expression through wingless and shaven-baby, and RNAi of forked phenocopied the effects of crinkled knockdown in T. castaneum. This study investigated the development role of crinkled in postembryonic stages and indicated that forked mediates the functions of crinkled during wing morphogenesis in T. castaneum.
Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/genética , Morfogênese/genética , Tribolium/genética , Asas de Animais/crescimento & desenvolvimento , Animais , Feminino , Proteínas de Insetos/metabolismo , Masculino , Interferência de RNA , Transdução de Sinais , Tribolium/crescimento & desenvolvimento , Tribolium/metabolismoRESUMO
Two-dimensional gel electrophoresis (2-DE) was used to detect fluoride-induced alterations in the proteome of the rat hippocampus. Male Sprague-Dawley rats (n=30) were subjected to treatments three weeks after weaning. Animals of the first group were injected intraperitoneally (i.p.) with aqueous NaF (20 mg/kg/body weight/day), the second group, injected with physiological saline, served as the control. After 30 days, the body weight of the fluoride-treated rats was lower than that of the control, and F- levels in serum were higher than in the control. The hippocampus was subjected to proteomic analysis, and the fluoride-treated group was found to contain 19 up-regulated and eight down-regulated proteins. The proteins, identified by mass-spectroscopic analysis of their fragments obtained after digestion, were found to be involved in amino acid biosynthesis, the insulin signaling pathway and various other crucial functions. Our results also provide useful information on the mechanism of the reduction of the learning ability and memory induced by F.
Assuntos
Hipocampo/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Proteoma , Fluoreto de Sódio/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Perfilação da Expressão Gênica , Hipocampo/metabolismo , Masculino , Proteínas do Tecido Nervoso/genética , Ratos , Ratos Sprague-DawleyRESUMO
Composite membranes were prepared from lignin alkali (LA), polyvinyl alcohol (PVA), and cellulose nanofibrils (CNF) using a simple, low-cost, and environmentally friendly method. The deodorization performances and structures of these membranes were also characterized. The sample referred to as L3C3P5 prepared with a solution containing 35.7â wt% LA, 53.6â wt% PVA, and 10.7â wt% CNF showed the best deodorization properties, and the H2S adsorption time reached 36â min. The adsorption performance was further improved by adding nano-CuO to the membrane, and the H2S adsorption time of the doped membrane L3C3P5C4 reached 60â min. While the H2S adsorption performance improved, structural analysis revealed that the addition of nano-CuO reduced the crystallinity in the membrane, caused the membrane to crack, and led to a decrease in the mechanical properties. The surface oxygens in the L3C3P5C4 membrane were primarily C-O bonds and lattice oxygens in CuO. After the H2S adsorption reaction, the lattice oxygen disappeared, and CuS products appeared.
Assuntos
Celulose , Lignina , Lignina/química , Celulose/química , Álcool de Polivinil , AdsorçãoRESUMO
PURPOSE: To evaluate the best endovascular treatment for de novo femoropopliteal lesions at long-term follow-up through network meta-analysis of randomized controlled trials. METHODS: Medical databases were searched on September 17, 2023. 17 trials and 7 treatments were selected. Outcomes were primary patency, target lesion revascularization (TLR), major amputation and all-cause mortality at 3 and/or 5 years. RESULTS: Regarding 3-year primary patency, drug-eluting stents (DES) was the best and better than balloon angioplasty (BA; odds ratio [OR], 4.96; 95% confidence interval [CI], 2.68-9.18), bare metal stents (BMS; OR, 2.81; 95% CI, 1.45-5.46), cryoplasty (OR, 6.75; 95% CI, 2.76-16.50), covered stents (CS; OR, 3.25; 95% CI, 1.19-8.87) and drug-coated balloons (DCB; OR, 2.04; 95% CI, 1.14-3.63). Regarding 5-year primary patency, DES was the best and better than BMS (OR, 2.34; 95% CI, 1.10-4.99). Regarding 3-year TLR, DES was the best and better than BA (OR, 0.24; 95% CI, 0.13-0.44). Regarding 5-year TLR, DES was the best and better than BA (OR, 0.20; 95% CI, 0.09-0.42) and balloon angioplasty with brachytherapy (OR, 0.21; 95% CI, 0.06-0.74). Regarding 3- and 5-year major amputation, DCB was the best. Regarding 3-year mortality, DES was the best and better than CS (OR, 0.09; 95% CI, 0.01-0.67). CONCLUSIONS: DES was the best treatment regarding 3-year primary patency, TLR and mortality, and DCB was the best regarding major amputation. DES was the best treatment regarding 5-year TLR, and DCB was the best regarding primary patency and major amputation. DES and DCB should be given priority in treating femoropopliteal lesions.
Assuntos
Angioplastia com Balão , Stents Farmacológicos , Doença Arterial Periférica , Humanos , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/cirurgia , Metanálise em Rede , Resultado do Tratamento , Grau de Desobstrução Vascular , Ensaios Clínicos Controlados Aleatórios como Assunto , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/cirurgia , Materiais Revestidos BiocompatíveisRESUMO
Conductive hydrogels have received increasing attention in the field of wearable electronics, but they also face many challenges such as temperature tolerance, biocompatibility, and stability of mechanical properties. In this paper, a double network hydrogel of MXene/TEMPO bacterial cellulose (TOBC) system is proposed. Through solvent replacement, the hydrogel exhibits wide temperature tolerance (-20-60 °C) and stable mechanical properties. A large number of hydrogen bonds, MXene/TOBC dynamic three-dimensional network system, and micellar interactions endow the hydrogel with excellent mechanical properties (elongation at break ~2800 %, strength at break ~420 kPa) and self-healing ability. The introduction of tannic acid prevents the oxidation of MXene and the loss of electrical properties of the hydrogel. In addition, the sensor can also quickly (74 ms) and sensitive (gauge factor = 15.65) wirelessly monitor human motion, and the biocompatibility can well avoid the stimulation when it comes into contact with the human body. This series of research work reveals the fabrication of MXene-like flexible wearable electronic devices based on self-healing, good cell compatibility, high sensitivity, wide temperature tolerance and durability, which can be used in smart wearable, wireless monitoring, human-machine Interaction and other aspects show great application potential.
Assuntos
Celulose , Hidrogéis , Humanos , Condutividade ElétricaRESUMO
High internal phase Pickering emulsions (HIPEs) constitute a significant research domain within colloid interface chemistry, addressing the demand for robust emulsion systems across various applications. An innovative nanoparticle, synthesized from a cyclodextrin metal-organic framework encapsulated with a composite of resveratrol and soy isolate protein (RCS), was employed to fortify a high internal phase emulsion. The emulsion's three-dimensional printing capabilities, alongside the encapsulated delivery efficacy for ß-carotene, were thoroughly examined. Cyclodextrin metal-organic frameworks (CD-MOFs), facilitated by cellulose nanofibrils, were synthesized to yield particles at the nanoscale, maintaining a remarkable 97.67 % cellular viability at an elevated concentration of 1000 µg/ml. The RCS nanoparticles demonstrated thermal stability and antioxidant capacities surpassing those of CD-MOF. The integration of soybean isolate protein augmented both the hydrophobicity (from 21.95 ± 0.64° to 59.15 ± 0.78°) and the interfacial tension (from 14.36 ± 0.46 mN/m to 5.34 ± 0.81 mN/m) of the CD-MOF encapsulated with resveratrol, thereby enhancing the RCS nanoparticles' adsorption at the oil-water interface with greater stability. The durability of the RCS-stabilized high internal phase emulsions was contingent upon the RCS concentration. Emulsions stabilized with 5 wt%-RCS exhibited optimal physical and chemical robustness, demonstrating superior performance in emulsion 3D printing and ß-carotene encapsulation delivery. This investigation furnishes a novel perspective on the amalgamation of food customization and precision nutrition.
Assuntos
Ciclodextrinas , Emulsões , Estruturas Metalorgânicas , Resveratrol , Proteínas de Soja , beta Caroteno , Proteínas de Soja/química , Resveratrol/química , Resveratrol/farmacologia , beta Caroteno/química , Emulsões/química , Estruturas Metalorgânicas/química , Ciclodextrinas/química , Humanos , Materiais Biocompatíveis/química , Antioxidantes/química , Antioxidantes/farmacologia , Nanopartículas/química , Portadores de Fármacos/químicaRESUMO
To accurately determine the effective extraction radius of directional long drilling, the influence of the negative pressure of the hole mouth, the drilling diameter, and the drilling length of the hole on the effective extraction radius of a directional long drilling hole is simulated by establishing a coal-to-gas gas-structure coupling model considering the Klinkenberg effect. Finally, the reliability of the numerical simulation is verified through field testing in Yuxi Coal Mine. The results reveal that the attenuation of negative pressure in a directional long borehole along a long hole has a significant influence on the gas extraction effect. The radial gas pressure of the extraction drilling hole is distributed in a "V" shape when the negative pressure of the extraction decays along the direction of the hole length. The higher the negative pressure and the longer the diameter of the drilling hole, the higher is the gas extraction effect. The effective extraction radius is exponentially related to the drilled hole depth when the negative pressure of extraction is attenuated along the long hole direction. The negative pressure of the hole and the diameter of the borehole are linearly related to the effective extraction radius at the depth of drilling hole of 430 m. Through field tests, while extracting for 180 days based on the stubble pressing effect, the effective extraction radius of the directional long borehole of the No. 3 coal seam of Yuxi Coal Mine is 5.7 m, and the absolute error between the numerical simulation is 0.1 m. In addition, the gas pressure obtained from different sampling points is consistent with the numerical simulation. The relative error is 0.3-4.1%. The results provide a theoretical basis for the rational layout of directional drilling.
RESUMO
Responsive antimicrobial materials can control and slow the release of antimicrobial agents smartly by responding to the stimulation of environmental conditions. In this study, we designed the pH-responsive cellulose-based nanoparticles (TOCNC-g-PEI) with amino and carboxyl groups by grafting polyethyleneimine (PEI) to carboxylated cellulose nanocrystals. Finally, the Pickering emulsion was endowed with smart antimicrobial properties by emulsifying the oregano essential oil (OEO) with nanoparticles. The TOCNC-g-PEI25000 had uniform size, greater dispersion, and excellent antimicrobial properties. The contact angles of nanoparticles were 78.70 ± 1.13°, 55.80 ± 1.58° and 55.35 ± 1.56° at neutral conditions, pH 4.0 and 8.0, respectively. The nanoparticles were responding to pH stimulation. The developed emulsion (4:6, 1.30 wt%) had exceptionally stabilized and encapsulated 98.56 ± 1.22 % of the oil phase. The OEO released rapidly within 0-12 h and slowly at 12-36 h. The cumulative release rates quickly reached 93.60 ± 3.73 % (pH 4.0) and 83.25 ± 0.36 % (pH 8.0) and stabilized gradually. The antimicrobial rates of emulsion stimulated for 4 h reached 100 % at pH 4.0, and both of them exceeded 96.10 ± 2.49 % at pH 8.0. The response of Pickering emulsion to pH stimulating controlled release antimicrobial agents and achieved smart antimicrobial.
Assuntos
Anti-Infecciosos , Nanopartículas , Emulsões/química , Celulose/química , Nanopartículas/química , Anti-Infecciosos/farmacologia , Concentração de Íons de HidrogênioRESUMO
Microgels are soft, deformable, permeable, and stimuli-responsive microscopic polymeric particles that are now emerging as prospective multifunctional soft materials for delivery systems, interface stabilization, cell cultures and tissue engineering. Cellulose microgels are emerging biopolymeric microgels with unique characteristics such as abound hydroxyl structure, admirable designability, multiscale pore network and excellent biocompatibility. This review summarizes the fabrication strategies for microgel, then highlights the fabrication routes for cellulose microgels, and finally elaborates cellulose microgels' bright application prospects with unique characteristics in the fields of controlled release, interface stabilization, coating, purification, nutrition/drug delivery, and bio-fabrication. The challenges to be addressed for further applications and considerable scope for development in future of cellulose microgels are also discussed.
Assuntos
Microgéis , Microgéis/química , Celulose/química , Estudos Prospectivos , Polímeros/química , Sistemas de Liberação de MedicamentosRESUMO
Aflatoxin M1 (AFM1) contamination poses a serious threat to human health globally. Hence, it is necessary to develop reliable and ultrasensitive methods for the determination of AFM1 residue in food products at low levels. In this study, a novel polystyrene microsphere-mediated optical sensing (PSM-OS) strategy was constructed to solve the problems of low sensitivity and susceptibility to interference from the matrix in AFM1 determination. Polystyrene (PS) microspheres have the advantages of low cost, high stability, and controllable particle size. They can be useful optical signal probes for qualitative and quantitative analyses attributed to the fact that they have strong ultraviolet-visible (UV-vis) characteristic absorption peaks. Briefly, magnetic nanoparticles were modified with the complex of bovine serum protein and AFM1 (MNP150-BSA-AFM1), and biotinylated antibodies of AFM1 (AFM1-Ab-Bio). Meanwhile, PS microspheres were also functionalized with streptavidin (SA-PS950). In the presence of AFM1, a competitive immune reaction was triggered leading to the changes in AFM1-Ab-Bio concentrations on the surface of MNP150-BSA-AFM1. The complex of MNP150-BSA-AFM1-Ab-Bio binds with SA-PS950 to form the immune complexes due to the special binding of biotin and streptavidin. The remaining SA-PS950 in the supernatant was determined by UV-Vis spectrophotometer after magnetic separation, which positively correlated with the concentration of AFM1. This strategy allows for ultrasensitive determination of AFM1 with limits of detection as low as 3.2 pg/mL. It was also successfully validated for AFM1 determination in milk samples, and a high consistency was found with the chemiluminescence immunoassay. Overall, the proposed PSM-OS strategy can be used for the rapid, ultrasensitive, and convenient determination of AFM1, as well as other biochemical analytes.
Assuntos
Aflatoxina M1 , Leite , Humanos , Animais , Leite/química , Aflatoxina M1/análise , Microesferas , Poliestirenos/análise , Estreptavidina , Contaminação de Alimentos/análiseRESUMO
Current biosensing detection assays were developed to focus on rapid, low-cost, stable detection for clinical diagnosis and food safety monitoring. In this work, a novel portable cartridge voltage-sensitive micropump immunosensor (CVMS) biosensing device based on the integration of the microchannel circuit biosensing principle and polydopamine (PDA) was presented for rapid and sensitive detection of pathogenic factors in real samples at trace levels. The CVMS can sensitively evaluate voltage signal changes caused by clogging effects in the closed-loop circuit when the insulated microspheres pass through the microchannel. The targets could trigger the immune reaction between antibody-antigens that leads to the change in the concentration of horseradish peroxidase (HRP). And the HRP was further employed to catalyze the polymerization of dopamine into PDA, resulting in the rapid formation of the magnetic @PDA nanoparticles (MNP@PDA) with core-shell structures. The abundant functional groups on the MNP@PDA surface can efficiently adsorb polystyrene microspheres, thus causing changes in the number of polystyrene microspheres (PS). The CVMS can accurately monitor the change of PS with a portable device, which weighs less than 0.8 kg and costs only $50. The completion of CVMS takes 90 min to complete. The limit of detection of this immunosensor for procalcitonin and ochratoxin A were 42 pg/mL and 77 pg/mL, respectively, which improved about 15 folds and 38 folds, respectively, than those of enzyme-linked immunosorbent assay.
Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Técnicas Biossensoriais/métodos , Poliestirenos/química , Imunoensaio/métodos , Polímeros/química , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodosRESUMO
Three novel Co-based coordination polymers including {[Co(L)(µ3-O)1/3]2}n (1), {[Co(L)(bimb)]}n (2) and {[Co(L)(bimmb)1/2]}n (3) (H2L = 2,6-di(4-carboxylphenyl)-4-(4-(triazol-1-ylphenyl))pyridine), bimb = 1,4-bis(lmidazol) butane, bimmb = 1,4-bis(imidazole-1-ylmethyl)benzene) were successfully prepared under solvothermal conditions and characterized. Single-crystal X-ray diffraction analyses revealed that 1 possesses a 3D architecture composed of a trinuclear cluster [Co3N3(CO2)6(µ3-O)], 2 exhibits a 2D new topological framework with the point symbol (84·122)(8)2, whereas 3 shows a unique six-fold interpenetrated 3D framework with a (63·82·10)2(63)2(8) topology. Impressively, all of them can function as a highly selective and sensitive fluorescent sensor for the biomarker methylmalonic acid (MMA) via fluorescence quenching. The low detection limit, reusability and high anti-interference performance together make 1-3 become promising sensors for the practical detection of MMA. Furthermore, the successful application of MMA detection in urine sample was demonstrated, which may be a potential candidate for the further development of clinical diagnostic tools.
Assuntos
Benzeno , Ácido Metilmalônico , Biomarcadores , Corantes , PolímerosRESUMO
Soybean-oil-based polymer is a promising bio-based water barrier coating on paper packaging but the application is challenged due to its poor water dispersibility. In this present study, 3-aminopropyltriethoxysilane (APTES) modified nanocrystalline cellulose (NCC) was used to implement a stable dispersion of acrylated epoxidized soybean oil (AESO) in water and thus synergistically improved the water vapor barrier properties after coating on paper. APTES-NCC was successfully prepared, and displayed a better interface compatibility with AESO through the Michael addition reaction. Compared with NCC, APTES-NCC displayed an improved hydrophobicity and wettability with AESO, with an increase of contact angle from 38.0° to 76.4°, and a decrease of interfacial tension from 91.5 ± 3.5 mN/m to 82.9 ± 1.8 mN/m. As an emulsifier, APTES-NCC can be more effectively adsorbed on the oil-water interface to form a more stable emulsion than NCC, with a decrease of AESO droplets size from 4.8 µm to 3.1 µm, and a remarkable improvement in static and centrifugal stability. In rheological measurement, the APTES-NCC/AESO emulsion showed a wider linear viscoelastic region (3.4%), better viscoelasticity and thermal curing properties than that of NCC/AESO emulsion, which further explained that the stability of APTES-NCC/AESO emulsion were improved. Therefore, APTES-NCC/AESO emulsion as a coating on paper cured into a continuous barrier film can effectively improve the water vapor barrier properties of paper, and the water vapor transmission rate (WVTR) of paper can be reduced from 1392.8 g/m2â¢24 h (NCC/AESO emulsion-coated) to 1286.3 g/m2 24 h (APTES-NCC/AESO emulsion-coated), both are significantly lower than that of base paper (1926.7 g/m2â¢24 h). CLSM testing showed that APTES-NCC could interact effectively with AESO to forming a tight barrier on paper surface and at the same time, sealing the pores inside the paper to resist water vapor penetration. The high-stable AESO emulsion prepared by APTES-NCC is expected to facilitate the utilization of NCC and AESO as a value-added material in making sustainable barrier packaging.
Assuntos
Glycine max , Vapor , Acrilatos , Celulose , Emulsões , Vapor/análiseRESUMO
The prevention of grain storage pests is a universal concern all over the world. It is in high demand to explore novel, safe and green insecticidal techniques to address such concerns. In this work, both raw and calcined diatomite were used as a natural insecticide to remove common grain storage pests with improved lethal effect on the saw-toothed grain beetle. Interestingly, the raw diatomite showed higher insecticidal efficiency than the calcined diatomite, and its associated insecticidal properties and preparation conditions were also optimized through orthogonal tests. The optimal conditions for processing the raw diatomite insecticide were identified as follows: the diatomite dust was 500 mesh (A 3), the temperature was 25 °C (B 1), the relative humidity was 65% (C 2), the diatomite dosage was 20 g m-2 (D 2), the influence factor order was C ≥ D > A > B. The observation of surface morphology indicated that the raw diatomite had a complete, multi hole surface morphology and good adsorption performance, whereas the structure of the calcined diatomite was uncomplete with collapsed pores, resulting in poor adsorption performance. The special pore structure and excellent adsorption capacity of diatomite make the stored grain pests lose water to lethal effect. Acute toxicity and long-term toxicity tests in mice showed that diatomite has no harmful effects on mammals. The findings from our work led to a green and effective approach in producing a highly efficient and safe storage grain insecticide.