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1.
Plant Mol Biol ; 108(4-5): 429-442, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34792751

RESUMO

KEY MESSAGE: The production of high-amylose cassava through CRISPR/Cas9-mediated mutagenesis of the starch branching enzyme gene SBE2 was firstly achieved. High-amylose cassava (Manihot esculenta Crantz) is desirable for starch industrial applications and production of healthier processed food for human consumption. In this study, we report the production of high-amylose cassava through CRISPR/Cas9-mediated mutagenesis of the starch branching enzyme 2 (SBE2). Mutations in two targeted exons of SBE2 were identified in all regenerated plants; these mutations, which included nucleotide insertions, and short or long deletions in the SBE2 gene, were classified into eight mutant lines. Three mutants, M6, M7 and M8, with long fragment deletions in the second exon of SBE2 showed no accumulation of SBE2 protein. After harvest from the field, significantly higher amylose (up to 56% in apparent amylose content) and resistant starch (up to 35%) was observed in these mutants compared with the wild type, leading to darker blue coloration of starch granules after quick iodine staining and altered starch viscosity with a higher pasting temperature and peak time. Further 1H-NMR analysis revealed a significant reduction in the degree of starch branching, together with fewer short chains (degree of polymerization [DP] 15-25) and more long chains (DP>25 and especially DP>40) of amylopectin, which indicates that cassava SBE2 catalyzes short chain formation during amylopectin biosynthesis. Transition from A- to B-type crystallinity was also detected in the starches. Our study showed that CRISPR/Cas9-mediated mutagenesis of starch biosynthetic genes in cassava is an effective approach for generating novel varieties with valuable starch properties for food and industrial applications.


Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana/genética , Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Amilose/metabolismo , Manihot/metabolismo , Raízes de Plantas/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Edição de Genes , Técnicas de Inativação de Genes , Genes de Plantas , Manihot/genética , Mutagênese , Plantas Geneticamente Modificadas/metabolismo
2.
Anal Chem ; 94(51): 17835-17842, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36508733

RESUMO

The low photon energy and deep penetrating ability of near-infrared (NIR) light make it an ideal light source for a photoelectrochemical (PEC) immunosensing system. Absorption wavelengths of the metal-organic frameworks (MOFs) can be regulated by adjusting the metal ions and the conjugation degree of the ligands. Herein, an ionic liquid with a large conjugated structure was synthesized and was used as a ligand to coordinate with Nd ions to prepare Nd-MOF nanorods with a band gap of 1.26 eV. The Nd-MOF rods show a good photoabsorption property from 200 to 980 nm. A PEC platform was constructed by using Nd-MOF nanorods as the photoelectroactive element. A detachable double-stranded DNA labeled with alkaline phosphatase (ALP), which is specific to VEGF165, was immobilized onto the PEC sensing interface. After blocking unspecific active sites with bovine albumin, an NIR PEC aptasensing system was developed for VEGF165 detection. After being incubated in a mixture of VEGF165, l-ascorbic acid 2-phosphate (magnesium salt hydrate) (AAP), and chloroauric acid, the aptamers for VEGF165 were detached from the PEC aptasensing interface, thus resulting in the decrease of the charge-transfer resistance and the increase of the photocurrent response. The shedding of the aptamers also makes the ALP approach the electrode surface, thus catalyzing the reduction of AAP to produce ascorbic acid (AA). Subsequently, AA reduces in situ chloroauric acid to produce AuNPs on the Nd-MOF-based sensing interface. With the excellent conductivity and localized surface plasmon resonance effect, the AuNPs can accelerate the separation of electron-hole pairs generated from Nd-MOF nanorods, thus promoting the photoelectric conversion efficiency and achieving signal amplification. Under optimized conditions, the PEC responses were linearly related to the VEGF165 concentrations in the range of 0.01-100 ng mL-1 and exhibit a low detection limit of 3.51 pg mL-1 (S/N = 3). VEGF165 in human serum samples was detected by the NIR PEC aptasensor. Their concentrations were found to be well consistent with that obtained from ELISA. Furthermore, the PEC aptasensor demonstrated recoveries from 96.07 to 103.8%. The relative standard deviations were within 5%, indicating good accuracy and precision. The results further verify its practicability for clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Líquidos Iônicos , Nanopartículas Metálicas , Nanotubos , Animais , Bovinos , Humanos , Ouro/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Nanotubos/química , Técnicas Eletroquímicas/métodos , Limite de Detecção
3.
Anal Chem ; 92(1): 1534-1540, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31790576

RESUMO

Many studies have demonstrated that the extracellular domain of human epidermal growth factor receptor 2 (HER2 ECD) level in serum can act as a breast cancer biomarker and serve as a monitoring neoadjuvant therapy of breast cancer. In this study, we developed a sensitive ascorbic acid (AA)-mediated AuNBPs (gold nanobipyramids) growth method with NADH (reduced nicotinamide adenine dinucleotide I) assistance, and we further fabricated a high-resolution multicolor immunosensor for sensitive visual detection of HER2 ECD in serum by using AuNBPs as signal and antibody as recognition probe. The NADH-assisted AA-mediated method effectively suppressed color formation in the blank and greatly improved the sensitivity of mediating AuNBPs growth, allowing us to use a low concentration of AA to mediate AuNBPs growth to generate more colorful and clearer color changes. The proposed multicolor immunosensor has higher resolution and more color changes corresponding to HER2 ECD concentrations. It can be used to detect as low as 0.5 ng/mL of HER2 ECD by bare eye observation and 0.05 ng/mL of HER2 ECD by UV-visible spectrophotometry. Using the immunosensor, we have successfully detected HER2 ECD in human serum with a recovery of 94%-96% and an RSD (n = 5) < 5%. The results obtained with our immunosensor were consistent with those obtained with ELISA, verifying the immunosensor has good accuracy. The immunosensor exhibited a vivid multicolor change, has low visual detection limit, excellent specificity and reproducibility, and robust resistance to matrix. All the above features makes our immunosensor a promising assay for the early diagnosis of HER2-dependent breast cancers in clinical diagnosis.


Assuntos
Biomarcadores Tumorais/sangue , Técnicas Biossensoriais , Neoplasias da Mama/sangue , Corantes Fluorescentes/química , Imunoensaio , Receptor ErbB-2/sangue , Ácido Ascórbico/química , Corantes Fluorescentes/síntese química , Ouro/química , Humanos , Nanopartículas Metálicas/química , Estrutura Molecular , NAD/química , Tamanho da Partícula , Propriedades de Superfície
4.
Bioorg Chem ; 101: 103985, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32544739

RESUMO

Thirteen 18ß-glycyrrhetinic acid (GA) derivatives were obtained by reduction at C-11 position, oxidation at C-3 position and condensation at C-2 position of GA. Anti-microbial activity evaluation indicated that compounds 04, 05, 10, 13 and 14 showed more potent inhibitory activity against Staphylococcus aureus subsp. aureus, Staphylococcus epidermidis, Staphylococcus aureus than GA, especially compound 10, the inhibitory activity against Staphylococcus epidermidis was equaled with Ampicillin. Moreover, in vivo experiments exhibited that compound 10 also has anti-inflammatory effect, which could decrease about 59.69% TPA-induced ear edema of mice with the gavage treatment of 40.0 mg/mL. Immunohistochemistry results revealed that the effect of inhibition was related to inhibition of TPA-induced upregulation of the pro-inflammatory cytokines TNF-α and IL-1ß. Furthermore, compound 10 also significantly decreased the expression level of p65 in NF-κB signaling pathway. In general, compound 10, both with antibacterial and anti-inflammatory activities, was expected to become a promising bio-functional agent.


Assuntos
Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Ácido Glicirretínico/análogos & derivados , Animais , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Modelos Animais de Doenças , Ácido Glicirretínico/síntese química , Ácido Glicirretínico/uso terapêutico , Masculino , Camundongos
5.
Plant Cell Rep ; 39(1): 169, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31784770

RESUMO

In Materials and method section, a sweetpotato variety "Taizhong-6" (China national number 2013003) should be renamed as Ayamurasaki".

6.
Mikrochim Acta ; 187(12): 675, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33241461

RESUMO

A highly sensitive colorimetric sensing strategy based on enzyme@metal-organic framework (GAA@Cu-MOF) and IrO2/MnO2 nanocomposite was exploited innovatively for screening of α-glucosidase (GAA) inhibitors. IrO2/MnO2 nanocomposite exhibits excellent oxidase-mimicking activity which can directly catalyze the oxidation of 3,3,5,5,-tetramethylbenzidine (TMB) into a blue product with an absorption maximum at 652 nm. And GAA@Cu-MOF can decompose L-ascorbic acid-2-O-α-D-glucopyranosyl (AAG) to ascorbic acid (AA). The produced AA can destroy the IrO2/MnO2 nanocomposite and reduce its oxidase-like activity. However, the generation of AA is restricted when GAA inhibitors are added to the system, which allows the oxidase-like activity of the IrO2/MnO2 nanocomposite to be maintained. In view of this, a method for screening of GAA inhibitors was developed. In addition to enhancing the stability of GAA, the method can also effectively avoid the potential interference of H2O2 in the screening process of GAA inhibitors, which helps to improve the sensitivity of the method. Therefore, highly sensitive determination for acarbose and ascorbic acid are achieved with detection limits of 6.27 nM and 1.23 µM, respectively. The proposed method was successfully applied to screen potential GAA inhibitors from oleanolic acid derivatives. Graphical abstract.


Assuntos
Colorimetria/métodos , Inibidores de Glicosídeo Hidrolases/análise , Estruturas Metalorgânicas/química , Nanocompostos/química , alfa-Glucosidases/metabolismo , Acarbose/análise , Ácido Ascórbico/análise , Catálise , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Irídio/química , Limite de Detecção , Compostos de Manganês/química , Óxidos/química , alfa-Glucosidases/química
7.
Plant Cell Rep ; 38(11): 1439-1448, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31451933

RESUMO

KEY MESSAGE: Overexpressing the Cry1Aa gene in sweetpotato significantly reduced pest damage through disrupting the integrity of the midgut of Spodoptera litura larvae for resistance against target Lepidoptera insect pests in sweetpotato. Sweetpotato is susceptible to insect pests and diseases leading to yield losses during pest outbreaks. Lepidoptera insects such as S litura are especially important pests of sweetpotato. The effect of Cry1Aa gene on S. litura was investigated by overexpressing Cry1Aa gene in sweetpotato to relieve symptoms due to pest damage. When transgenic leaves were fed to the larvae of S. litura, the growth of the larvae was reduced, the larval quality decreased, and mortality was increased compared with the larvae that fed on wild-type leaves. Further anatomical analysis revealed that the columnar cells of the midgut epithelium of the BT group were significantly damaged, loosened, or disordered. Furthermore, the integrity of the midgut was destroyed. In addition, when potted seedlings of the wild-type and BT sweetpotato were inoculated with the same number of S. litura larvae, wild-type plants died on the eighth day after infestation, while BT transgenic lines still grew normally. This study showed that transgenic sweetpotato overexpressing Cry1Aa can prevent S. litura infestation, and thus increase the yield of sweetpotato.


Assuntos
Proteínas de Bactérias/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Ipomoea batatas/genética , Plantas Geneticamente Modificadas/genética , Spodoptera , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Larva/crescimento & desenvolvimento , Controle Biológico de Vetores , Folhas de Planta/genética , Spodoptera/crescimento & desenvolvimento
8.
Langmuir ; 34(48): 14537-14545, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30398355

RESUMO

In this work, we synthesize dodecyl mercaptan-functionalized silver nanoparticles integrated with polypropylene nanocomposite (DM-AgNPs/PP) substrates by a simple in situ melt blending method. The formation and distribution of AgNPs are confirmed by UV-visible spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and thermogravimetric analysis. The existence of DM-AgNPs in PP film substrate enhances the thermal degradation and crystallization properties. Further, the antimicrobial activity of as-synthesized DM-AgNPs/PP film substrate is studied using Gram-negative ( Escherichia coli) and Gram-positive ( Staphylococcus aureus) bacteria as model microbes, which displayed significantly enhanced bacteriostatic activities under optimized composition and experimental conditions. Interestingly, PP substrate with 0.4% DM-AgNPs exhibits drastically improved antibacterial property via the release of oxygen reactive species and Ag ion diffusion processes; thus, the inhibition rates of E. coli and S. aureus are obtained as 100 and 84.6%, respectively, which is higher than the conventional AgNPs. Finally, we demonstrate the migration study of Ag ions from the DM-AgNPs/PP film using different food simulant solutions by inductively coupled plasma-mass spectrometry analysis and the dissolved Ag ion content is estimated, which is a key prospect for the toxicity analysis. The overall Ag ion migration value is estimated between 1.8 and 24.5 µg/cm2 and displayed a lowest limit of Ag ion migration as 0.36 µg/cm2. Our work highlights the development of high performance nanocomposites as promising antibacterial and food simulant materials for biomedical and industrial applications.


Assuntos
Alimentos , Nanopartículas Metálicas/química , Nanocompostos/química , Polipropilenos/química , Prata/química , Prata/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Transição de Fase , Staphylococcus aureus/efeitos dos fármacos , Temperatura
9.
J Sci Food Agric ; 97(13): 4476-4483, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28295389

RESUMO

BACKGROUND: Sinonovacula constricta is an economically and nutritionally important bivalve native to the estuaries and mudflats of China, Japan and Korea. In the present study, S. constricta, cultured either under experimental conditions or collected directly from natural coastal areas with different seawater salinities, was investigated for changes in proximates, amino acids and lipids. RESULTS: When culture salinity was increased, levels of moisture, carbohydrate, crude protein and crude lipid were significantly decreased, whereas the level of ash was significantly increased. The level of Ala was increased by 1.5- to 2-fold, whereas the contents of most lipids were significantly decreased, and the proportion of phosphatidylethanolamine was significantly increased. Notably, a high proportion of ceramide aminoethylphosphonates was detected in S. constricta reared at all salinities. The energy content appears to be higher in S. constricta reared at higher salinity. In experimental S. constricta, when the salinity was enhanced, the changes of compositions were very close to those reared at constant high salinity. CONCLUSION: Sinonovacula constricta reared at higher salinities possesses a superior quality. A short period of exposure to a higher salinity for farmed S. constricta reared at a lower salinity before harvest would be useful with respect to improving its nutritive value. © 2017 Society of Chemical Industry.


Assuntos
Aminoácidos/química , Bivalves/química , Lipídeos/química , Frutos do Mar/análise , Animais , Bivalves/crescimento & desenvolvimento , Salinidade , Água do Mar/química
10.
J Phycol ; 51(2): 264-76, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26986522

RESUMO

The two morphologically similar microalgae NMBluh014 and NMBluh-X belong to two different strains of Nannochloropsis oceanica. They possess obviously different feeding effects on bivalves, but are indistinguishable by 18S rRNA and morphological features. In this work, lipidomic analysis followed by principal component analysis and orthogonal projections to latent structures discriminant analysis provided a clear distinction between these strains. Metabolites that definitively contribute to the classification were selected as potential biomarkers. The most important difference in polar lipids were sulfoquinovosyldiacylglycerol (containing 18:1/16:0 and 18:3/16:0) and monogalactosyldiacylglycerol (containing 18:3/16:3 and 20:5/14:0), which were detected only in NMBluh-X. Additionally, an exhaustive qualitative and quantitative profiling of the neutral lipid triacylglycerol (TAG) in the two strains was carried out. The predominant species of TAG containing 16:1/16:1/16:1 acyl groups was detected only in NMBluh-X with a content of ~93.67 ± 11.85 nmol · mg(-1) dry algae at the onset of stationary phase. Meanwhile, TAG containing 16:0/16:0/16:0 was the main TAG in NMBluh014 with a content of 40.25 ± 3.92 nmol · mg(-1) . These results provided the most straightforward evidence for differentiating the two species. The metabolomic profiling indicated that NMBluh-X underwent significant chemical and physiological changes during the growth process, whereas NMBluh014 did not show such noticeable time-dependent metabolite change. This study is the first using Ultra Performance Liquid Chromatography coupled with Electrospray ionization-Quadrupole-Time of Flight Mass Spectrometry (UPLC-Q-TOF-MS) for lipidomic profiling with multivariate statistical analysis to explore lipidomic differences of plesiomorphous microalgae. Our results demonstrate that lipidomic profiling is a valid chemotaxonomic tool in the study of microalgal systematics.

11.
Anal Chim Acta ; 1298: 342408, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38462333

RESUMO

BACKGROUND: In vitro screening strategies based on the inhibition of α-glucosidase (GAA) activity have been widely used for the discovery of potential antidiabetic drugs, but they still face some challenges, such as poor enzyme stability, non-reusability and narrow range of applicability. To overcome these limitations, an in vitro screening method based on GAA@GOx@Cu-MOF reactor was developed in our previous study. However, the method was still not satisfactory enough in terms of construction cost, pH stability, organic solvent resistance and reusability. Thence, there is still a great need for the development of in vitro screening methods with lower cost and wider applicability. RESULTS: A colorimetric sensing strategy based on GAA/(Au-Au/IrO2)@Cu(PABA) cascade catalytic reactor, which constructed through simultaneous encapsulating Au-Au/IrO2 nanozyme with glucose oxidase-mimicking and peroxidase-mimicking activities and GAA in Cu(PABA) carrier with peroxidase-mimicking activity, was innovatively developed for in vitro screening of GAA inhibitors in this work. It was found that the reactor not only exhibited excellent thermal stability, pH stability, organic solvent resistance, room temperature storage stability, and reusability, but also possessed cascade catalytic performance, with approximately 12.36-fold increased catalytic activity compared to the free system (GAA + Au-Au/IrO2). Moreover, the in vitro GAA inhibitors screening method based on this reactor demonstrated considerable anti-interference performance and detection sensitivity, with a detection limit of 4.79 nM for acarbose. Meanwhile, the method owned good reliability and accuracy, and has been successfully applied to the in vitro screening of oleanolic acid derivatives as potential GAA inhibitors. SIGNIFICANCE: This method not only more effectively solved the shortcomings of poor stability, narrow scope of application, and non-reusability of natural enzymes in the classical method compared with our previous work, but also broaden the application scope of Au-Au/IrO2 nanozyme with glucose oxidase and peroxidase mimicking activities, and Cu(PABA) carrier with peroxidase mimicking activity, which was expected to be a new generation candidate method for GAA inhibitor screening.


Assuntos
Ácido 4-Aminobenzoico , Inibidores de Glicosídeo Hidrolases , Inibidores de Glicosídeo Hidrolases/farmacologia , Glucose Oxidase , Reprodutibilidade dos Testes , Colorimetria/métodos , Peroxidases , Solventes , Peróxido de Hidrogênio
12.
Anal Chim Acta ; 1326: 343150, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39260918

RESUMO

BACKGROUND: To minimize the impact of pesticide residues in food on human health, it is necessary to enhance their detection. Recently, many nanozyme-based colorimetric methods for pesticides detection have been developed, however, they often required the assistance of natural enzymes, which made the process and result of methods susceptible to the stability and activity of natural enzymes. To overcome these drawbacks, methods for direct detection of pesticides using nanozymes have been developed, and there are few studies in this field currently. Thus, it is of great research and practical significance to develop more nanozymes-based colorimetric methods for direct detection of pesticides. RESULTS: Dual colorimetric platforms based on Os-Rh nanozyme with excellent peroxidase-like activity were constructed for directly detection of glyphosate in this work. Results showed that glyphosate was able to sensitively and selectively inhibit the peroxidase-like activity of Os-Rh nanozyme through hindering the decomposition of H2O2 by Os-Rh nanozyme to produce HO∙. Based on this, the dual colorimetric platforms achieved highly sensitive detection for glyphosate over a wide linear concentration range (50-1000 µg L-1 in solution platform and 200-1000 µg L-1 in paper platform), with the detection limits of 28.37 µg L-1 in solution platform and 400 µg L-1 (naked-eye detection limit)/123.25 µg L-1 (gray scale detection limit) in paper platform, respectively. Moreover, the dual colorimetric platforms possessed satisfactory reliability and accuracy for practical applications, and has been successfully applied to the detection of real samples with the spiked recoveries of 92.78-102.75 % and RSD of 1.17-3.88 %. SIGNIFICANCE: The dual colorimetric platforms for glyphosate direct detection based on Os-Rh nanozyme developed in this work not only owned considerable practical application potential, but also could provide more inspirations and ideas for the rational design and development of colorimetric sensing methods for the rapid detection of pesticides based on nanozymes.


Assuntos
Colorimetria , Glicina , Glifosato , Colorimetria/métodos , Glicina/análogos & derivados , Glicina/análise , Glicina/química , Peroxidase/metabolismo , Peroxidase/química , Limite de Detecção , Peróxido de Hidrogênio/química
13.
Front Microbiol ; 15: 1447921, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39234550

RESUMO

Introduction: The relationships among microelements and soil microbial communities are essential for understanding the maintenance of soil's ecological functions and their effects on fruit quality in orchards. However, these relationships have not been adequately studied, despite the importance of microelements for the growth of microorganisms and plants. Methods: To address this research gap, we investigated the relationships among microelements (K, Ca, Na, Mg, Fe, Mn, Zn, and Cu), the diversity and composition of soil microbiomes, and fruit quality in loquat orchards. Results: We found that microelements explained more variations in microbial community structures than geographic position, basic soil properties, and macroelements, with 19.6-42.6% of bacterial, 4.3-27.7% of fungal, and 5.9-18.8% of protistan genera significantly correlated with microelements. Among the microelements, AMg and ACu were the most influential in determining the soil microbiome. The soil microbes exhibited varied threshold values for environmental breadth among the microelements, with the broadest range for AMg and the narrowest for AZn. Additionally, the microbes showed significant phylogenetic signals for all microelements, with an increasing divergence of soil microelements. The dominant community assembly shifted from homogeneous selection to stochastic, and then to heterogeneous selection. Moreover, microelements and the microbiome were the top two factors individually explaining 11.0 and 11.4% of fruit quality variation, respectively. Discussion: These results highlight the importance of microelement fertilization in orchard management and provide scientific guidance for improving fruit quality.

14.
Biosens Bioelectron ; 224: 115033, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36621082

RESUMO

Staphylococcus aureus is one of the most prevalent threats to public health. Rapid detection with high sensitivity and targeted killing is crucial to curb its spread. Herein, a metal-bearing nanocomposite, consisting of a bimetallic nanoparticle and a metal-organic framework (Au/Ir@Cu/Zn-MOF) was constructed. Upon conjugation with anti-S. aureus antibody, this nanocomposite (Ab-Au/Ir@Cu/Zn-MOF) was exploited for its dual functions, i.e. as a reporting probe in a lateral flow immunoassay and a high efficiency antibacterial reagent. Benefiting from the enrichment of Au/Ir NPs by the Cu/Zn-MOF, the Au/Ir@Cu/Zn-MOF-based lateral flow immunoassay sensor exhibited a visual limit of detection of 103 CFU/mL, which was100 times more sensitive than Au/Ir-based sensor. Moreover, the Ab-Au/Ir@Cu/Zn-MOF probe possessed synergistic photothermal-chemodynamic bactericidal effect that specifically targeted against S. aureus. Under a co-treatment by H2O2 (0.4 mM) and 808 nm near infrared irradiation (1 W/cm2, 5 min), complete sterilization of 5 × 105-106 CFU/mL S. aureus was achieved at a nanocomposite concentration as low as 6.25 µg/mL. The superior antibacterial efficiency was attributable to the three-fold properties of the Ab-Au/Ir@Cu/Zn-MOF probe: (1) enhanced multi-enzyme mimicking activities that promote reactive oxygen species generation, (2) high photothermal activity (efficiency of 53.70%), and (3) bacteria targeting ability via the antibody coating. By changing the antibody, this nanocomposite can be tailored to target a wide range of bacteria species, for detection and for precise antibacterial treatment.


Assuntos
Técnicas Biossensoriais , Imunoconjugados , Nanopartículas Metálicas , Peróxido de Hidrogênio , Bactérias , Anticorpos , Antibacterianos/farmacologia , Imunoensaio , Staphylococcus aureus , Zinco
15.
ACS Appl Mater Interfaces ; 15(14): 17675-17687, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37001053

RESUMO

Effective wound care and treatment require a quick and comprehensive assessment of healing status. Here, we develop a carbon dot-doped hydrogel sensor array in polydimethylsiloxane (PDMS) for simultaneous colorimetric detections of five wound biomarkers and/or wound condition indicators (pH, glucose, urea, uric acid, and total protein), leading to the holistic assessment of inflammation and infection. A biogenic carbon dot synthesized using an amino acid and a polymer precursor is doped in an agarose hydrogel matrix for constructing enzymatic sensors (glucose, urea, and uric acid) and dye-based sensors (pH and total protein). The encapsulated enzymes in such a matrix exhibit improved enzyme kinetics and stability compared to those in pure hydrogels. Such a matrix also provides stable colorimetric responses for all five sensors. The sensor array exhibits high accuracy (recovery rates of 91.5-113.1%) and clinically relevant detection ranges for all five wound markers. The sensor array is established for simulated wound fluids and validated with rat wound fluids from perturbed wound models. Distinct color patterns are obtained that can clearly distinguish healing vs nonhealing wounds visually and quantitatively. This hydrogel sensor array shows great potential for on-site wound sensing due to its long-term stability, lightweight, and flexibility.


Assuntos
Colorimetria , Hidrogéis , Ratos , Animais , Hidrogéis/química , Carbono/química , Ácido Úrico , Cicatrização , Ureia , Glucose
16.
Talanta ; 258: 124377, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36863068

RESUMO

A dual-mode biosensor constructed based on photoelectrochemical (PEC) and electrochemical (EC) property was developed for assaying circulating tumor DNA (ctDNA), which is commonly used for triple-negative breast cancer diagnosis. Ionic liquid functionalized two-dimensional Nd-MOF nanosheets were successfully synthesized through a template-assisted reagent substituting reaction. Nd-MOF nanosheets integrated with gold nanoparticles (AuNPs) were able to improve photocurrent response and supply active sites for assembling sensing elements. To achieve selective detection of ctDNA, thiol-functionalized capture probes (CPs) were immobilized on the Nd-MOF@AuNPs modified glassy carbon electrode surface, thereby generating a "signal-off" photoelectrochemical biosensor for ctDNA under visible light irradiation. After the recognition of ctDNA, ferrocene-labeled signaling probes (Fc-SPs) were introduced into the biosensing interface. After hybridization between ctDNA and Fc-SPs, the oxidation peak current of Fc-SPs generated from square wave voltammetry can be employed as a "signal-on" electrochemical signal for ctDNA quantification. Under the optimized conditions, a linear relationship was obtained to the logarithm of ctDNA concentration in between 1.0 fmol L-1 to 10 nmol L-1 for the PEC model and 1.0 fmol L-1 to 1.0 nmol L-1 for the EC model. The dual-mode biosensor can provide accurate results for ctDNA assays, effectively eliminating the probable occurrence of false-positive or false-negative results in single-model assays. By switching DNA probe sequences, the proposed dual-mode biosensing platform can serve as a strategy for detecting other DNAs and possesses broad applications in bioassay and early disease diagnosis.


Assuntos
Técnicas Biossensoriais , Líquidos Iônicos , Nanopartículas Metálicas , Ouro/química , Líquidos Iônicos/química , Nanopartículas Metálicas/química , DNA/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Limite de Detecção
17.
Int J Anal Chem ; 2022: 7306597, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35971426

RESUMO

In order to understand and improve the degradation rate of formaldehyde, the study on the chemical structure and thermal properties of nano-titanium dioxide resin by free formaldehyde was proposed. In this research, nano-titanium dioxide was prepared by the low temperature hydrolysis method and characterized by using the scanning electron microscope (SEM) and X-ray diffraction (XRD). The degradation behavior of formaldehyde was studied by using the degradation rate of formaldehyde in the container as the evaluation index. The influence of the photocatalytic coating on the degradation rate of formaldehyde under different loading conditions, different temperatures, and different humidity was investigated. The experimental results show that the formaldehyde degradation rate of the photocatalytic coating prepared by loading 5 g nano-TiO2 into a 200 g emulsion system can reach 93% under the conditions of room temperature of 25°C, humidity of 50%, and UV lamp irradiation of 120 min. Conclusion. This study is obviously better than the commercial P25 nano-titanium dioxide degradation effect of formaldehyde.

18.
Comb Chem High Throughput Screen ; 25(13): 2255-2263, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35088661

RESUMO

BACKGROUND: Lung adenocarcinoma (LUAD) is a highly heterogeneous malignant tumor. Therefore, it is necessary to find predictive biomarkers related to the prognosis and immune infiltration of lung adenocarcinoma, which may provide an effective theoretical basis for its clinical treatment. OBJECTIVE: This study aimed to evaluate whether the expression level of PHD3 in lung adenocarcinoma (LUAD) is related to immunity. METHODS: PHD3 expression was analyzed by the ONCOMINE, TIMER, UALCAN, and GEPIA databases. The correlations between clinical information and PHD3 expression were analyzed by the LinkedOmics database. Then, we evaluated the influence of PHD3 on the survival of LUAD patients using Kaplan-Meier Plotter and HPA database. We explored the correlation between PHD3 and tumor immunity using TIMER and the correlation module of TISDIB. Finally, we used the cBioportal database to analyze PHD3 mutations in LUAD. RESULTS: Comprehensive analysis displayed PHD3 expression to be clearly higher in LUAD compared to adjacent normal tissues. PHD3 expression was identified to be positively associated with tumor purity, histological type, and later pathological stage. Survival curve results revealed the high expression of PHD3 in LUAD patients to be accompanied by a poor prognosis. Further study indicated PHD3 to be significantly related to a variety of tumor immune cells and molecules. Moreover, among the LUAD cases with gene alteration of PHD3, amplification was the most common of all alteration types. CONCLUSION: PHD3 may be used as a biomarker for survival and immunotherapy of LUAD.


Assuntos
Adenocarcinoma de Pulmão , Prolil Hidroxilases , Humanos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/patologia , Biomarcadores Tumorais/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia
19.
ACS Nano ; 16(12): 19840-19872, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36441973

RESUMO

Bacterial infections remain the leading cause of death worldwide today. The emergence of antibiotic resistance has urged the development of alternative antibacterial technologies to complement or replace traditional antibiotic treatments. In this regard, metal nanomaterials have attracted great attention for their controllable antibacterial functions that are less prone to resistance. This review discusses a particular family of stimuli-activable metal-bearing nanomaterials (denoted as SAMNs) and the associated on-demand antibacterial strategies. The various SAMN-enabled antibacterial strategies stem from basic light and magnet activation, with the addition of bacterial microenvironment responsiveness and/or bacteria-targeting selectivity and therefore offer higher spatiotemporal controllability. The discussion focuses on nanomaterial design principles, antibacterial mechanisms, and antibacterial performance, as well as emerging applications that desire on-demand and selective activation (i.e., medical antibacterial treatments, surface anti-biofilm, water disinfection, and wearable antibacterial materials). The review concludes with the authors' perspectives on the challenges and future directions for developing industrial translatable next-generation antibacterial strategies.


Assuntos
Infecções Bacterianas , Nanoestruturas , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias , Infecções Bacterianas/tratamento farmacológico , Biofilmes , Metais
20.
Polymers (Basel) ; 14(18)2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36146034

RESUMO

Microplastics are harmful to both marine life and humans. Herein, a pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS) technique for the detection of microplastics in aquatic shellfish is demonstrated. The organic matter in aquatic shellfish was removed by alkali digestion. Subsequently, using hexafluoroisopropanol as the extraction solvent, the extraction method was optimized. The influence of the digestion process on the nature of microplastics was investigated by analyzing the samples before and after the alkali treatment via infrared spectrometry, laser particle sizing, and scanning electron microscopy. Spiked recovery experiments and an analysis of actual samples were performed using PA6 and PA66 as analytes. A quantitative analysis of the characteristic ion fragment produced by high-temperature cracking was performed after chromatographic separation and mass spectrometry identification. The linear range of this method for PA6 and PA66 was 2-64 µg. The limits of detection of PA6 and PA66 were 0.2 and 0.6 µg, while the limits of quantitation were 0.6 and 2.0 µg, respectively. Recovery ranged from 74.4 to 101.62%, with a precision of 4.53-7.56%. The results suggest that the Py-GC/MS technique is suitable for the analysis and detection of trace microplastics in aquatic shellfish.

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