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1.
Nat Cell Biol ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997456

RESUMO

Gasdermin (GSDM) family proteins, known as the executors of pyroptosis, undergo protease-mediated cleavage before inducing pyroptosis. We here discovered a form of pyroptosis mediated by full-length (FL) GSDME without proteolytic cleavage. Intense ultraviolet-C irradiation-triggered DNA damage activates nuclear PARP1, leading to extensive formation of poly(ADP-ribose) (PAR) polymers. These PAR polymers are released to the cytoplasm, where they activate PARP5 to facilitate GSDME PARylation, resulting in a conformational change in GSDME that relieves autoinhibition. Moreover, ultraviolet-C irradiation promotes cytochrome c-catalysed cardiolipin peroxidation to elevate lipid reactive oxygen species, which is then sensed by PARylated GSDME, leading to oxidative oligomerization and plasma membrane targeting of FL-GSDME for perforation, eventually inducing pyroptosis. Reagents that concurrently stimulate PARylation and oxidation of FL-GSDME, synergistically promoting pyroptotic cell death. Overall, the present findings elucidate an unreported mechanism underlying the cleavage-independent function of GSDME in executing cell death, further enriching the paradigms and understanding of FL-GSDME-mediated pyroptosis.

3.
BMC Plant Biol ; 24(1): 286, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627660

RESUMO

Fruit length is a crucial agronomic trait of snake gourd (Trichosanthes anguina L); however, genes associated with fruit length have not been characterised. In this study, F2 snake gourd populations were generated by crossing the inbred lines, S1 and S2 (fruit lengths: 110 and 20 cm, respectively). Subsequently, bulk segregant analysis, sequencing, and fine-mapping were performed on the F2 population to identify target genes. Our findings suggest that the fruit length of snake gourd is regulated by a major-effect regulatory gene. Mining of genes regulating fruit length in snake gourd to provide a basis for subsequent selection and breeding of new varieties. Genotype-phenotype association analysis was performed on the segregating F2 population comprising 6,000 plants; the results indicate that the target gene is located on Chr4 (61,846,126-61,865,087 bp, 18.9-kb interval), which only carries the annotated candidate gene, Tan0010544 (designated TFL). TFL belongs to the MADS-box family, one of the largest transcription factor families. Sequence analysis revealed a non-synonymous mutation of base C to G at position 202 in the coding sequence of TFL, resulting in the substitution of amino acid Gln to Glu at position 68 in the protein sequence. Subsequently, an InDel marker was developed to aid the marker-assisted selection of TFL. The TFL in the expression parents within the same period was analysed using quantitative real-time PCR; the TFL expression was significantly higher in short fruits than long fruits. Therefore, TFL can be a candidate gene for determining the fruit length in snake gourd. Collectively, these findings improve our understanding of the genetic components associated with fruit length in snake gourds, which could aid the development of enhanced breeding strategies for plant species.


Assuntos
Trichosanthes , Trichosanthes/genética , Frutas/genética , Melhoramento Vegetal , Fenótipo , Genes de Plantas/genética
4.
Cell Death Differ ; 31(5): 635-650, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38493248

RESUMO

Diquat (DQ) poisoning is a severe medical condition associated with life-threatening implications and multiorgan dysfunction. Despite its clinical significance, the precise underlying mechanism remains inadequately understood. This study elucidates that DQ induces instability in the mitochondrial genome of endothelial cells, resulting in the accumulation of Z-form DNA. This process activates Z-DNA binding protein 1 (ZBP1), which then interacts with receptor-interacting protein kinase 3 (RIPK3), ultimately leading to RIPK3-dependent necroptotic and ferroptotic signaling cascades. Specific deletion of either Zbp1 or Ripk3 in endothelial cells simultaneously inhibits both necroptosis and ferroptosis. This dual inhibition significantly reduces organ damage and lowers mortality rate. Notably, our investigation reveals that RIPK3 has a dual role. It not only phosphorylates MLKL to induce necroptosis but also phosphorylates FSP1 to inhibit its enzymatic activity, promoting ferroptosis. The study further shows that deletion of mixed lineage kinase domain-like (Mlkl) and the augmentation of ferroptosis suppressor protein 1 (FSP1)-dependent non-canonical vitamin K cycling can provide partial protection against DQ-induced organ damage. Combining Mlkl deletion with vitamin K treatment demonstrates a heightened efficacy in ameliorating multiorgan damage and lethality induced by DQ. Taken together, this study identifies ZBP1 as a crucial sensor for DQ-induced mitochondrial Z-form DNA, initiating RIPK3-dependent necroptosis and ferroptosis. These findings suggest that targeting the ZBP1/RIPK3-dependent necroptotic and ferroptotic pathways could be a promising approach for drug interventions aimed at mitigating the adverse consequences of DQ poisoning.


Assuntos
DNA Mitocondrial , Ferroptose , Necroptose , Proteínas de Ligação a RNA , Proteína Serina-Treonina Quinases de Interação com Receptores , Animais , Humanos , Masculino , Camundongos , DNA Mitocondrial/metabolismo , DNA Mitocondrial/genética , Ferroptose/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Necroptose/efeitos dos fármacos , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Diquat/toxicidade
5.
Clin Neuropharmacol ; 47(1): 1-6, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38154072

RESUMO

INTRODUCTION: The ideal dose of lasmiditan for migraine is not clear. This meta-analysis aims to compare the efficacy of lasmiditan 200 mg versus 100 mg for migraine patients. METHODS: We have searched several databases including PubMed, Embase, Web of Science, EBSCO, and Cochrane Library Databases and selected the randomized controlled trials comparing the efficacy of lasmiditan 200 mg versus 100 mg for migraine patients. This meta-analysis was conducted using the random-effect model. RESULTS: Five randomized controlled trials were included in this meta-analysis. Compared with lasmiditan 100-mg group in migraine patients, lasmiditan 200-mg group was associated with substantially increased pain free at 2 hours (odds ratio [OR], 1.27; 95% confidence interval [CI], 1.12-1.44; P = 0.0002) and pain free at 24 hours (OR, 1.31; 95% CI, 1.08-1.60; P = 0.007) but demonstrated no obvious impact on pain relief at 2 hours (OR, 1.02; 95% CI, 0.91-1.16; P = 0.72) or MBS free at 2 hours (OR, 0.94; 95% CI, 0.77-1.14; P = 0.52). In addition, the incidence of adverse events was higher in lasmiditan 200-mg group than that in lasmiditan 100-mg group (OR, 1.29; 95% CI, 1.15-1.45; P < 0.0001). CONCLUSIONS: Lasmiditan 200 mg is better for the treatment of migraine patients than lasmiditan 100 mg.


Assuntos
Benzamidas , Transtornos de Enxaqueca , Piperidinas , Piridinas , Agonistas do Receptor de Serotonina , Humanos , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/induzido quimicamente , Agonistas do Receptor de Serotonina/uso terapêutico , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Sci Rep ; 13(1): 19265, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935703

RESUMO

Classic heatstroke (CHS) is a life-threatening illness characterized by extreme hyperthermia, dysfunction of the central nervous system and multiorgan failure. Accurate predictive models are useful in the treatment decision-making process and risk stratification. This study was to develop and externally validate a prediction model of survival for hospitalized patients with CHS. In this retrospective study, we enrolled patients with CHS who were hospitalized from June 2022 to September 2022 at 3 hospitals in Southwest Sichuan (training cohort) and 1 hospital in Central Sichuan (external validation cohort). Prognostic factors were identified utilizing least absolute shrinkage and selection operator (LASSO) regression analysis and multivariate Cox regression analysis in the training cohort. A predictive model was developed based on identified prognostic factors, and a nomogram was built for visualization. The areas under the receiver operator characteristic (ROC) curves (AUCs) and the calibration curve were utilized to assess the prognostic performance of the model in both the training and external validation cohorts. The Kaplan‒Meier method was used to calculate survival rates. A total of 225 patients (median age, 74 [68-80] years) were included. Social isolation, self-care ability, comorbidities, body temperature, heart rate, Glasgow Coma Scale (GCS), procalcitonin (PCT), aspartate aminotransferase (AST) and diarrhea were found to have a significant or near-significant association with worse prognosis among hospitalized CHS patients. The AUCs of the model in the training and validation cohorts were 0.994 (95% [CI], 0.975-0.999) and 0.901 (95% [CI], 0.769-0.968), respectively. The model's prediction and actual observation demonstrated strong concordance on the calibration curve regarding 7-day survival probability. According to K‒M survival plots, there were significant differences in survival between the low-risk and high-risk groups in the training and external validation cohorts. We designed and externally validated a prognostic prediction model for CHS. This model has promising predictive performance and could be applied in clinical practice for managing patients with CHS.


Assuntos
Golpe de Calor , Idoso , Humanos , Temperatura Corporal , Golpe de Calor/terapia , Nomogramas , Prognóstico , Estudos Retrospectivos , Idoso de 80 Anos ou mais
7.
Research (Wash D C) ; 6: 0179, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377457

RESUMO

Data-independent acquisition (DIA) technology for protein identification from mass spectrometry and related algorithms is developing rapidly. The spectrum-centric analysis of DIA data without the use of spectra library from data-dependent acquisition data represents a promising direction. In this paper, we proposed an untargeted analysis method, Dear-DIAXMBD, for direct analysis of DIA data. Dear-DIAXMBD first integrates the deep variational autoencoder and triplet loss to learn the representations of the extracted fragment ion chromatograms, then uses the k-means clustering algorithm to aggregate fragments with similar representations into the same classes, and finally establishes the inverted index tables to determine the precursors of fragment clusters between precursors and peptides and between fragments and peptides. We show that Dear-DIAXMBD performs superiorly with the highly complicated DIA data of different species obtained by different instrument platforms. Dear-DIAXMBD is publicly available at https://github.com/jianweishuai/Dear-DIA-XMBD.

8.
J Proteome Res ; 22(7): 2232-2245, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37256709

RESUMO

Phosphoproteomics and ubiquitinomics data-independent acquisition (DIA) mass spectrometry (MS) data is typically analyzed by using a data-dependent acquisition (DDA) spectral library. The performance of various library-free strategies for analyzing phosphoproteomics and ubiquitinomics DIA MS data has not been evaluated. In this study, we systematically compare four commonly used DDA library-free approaches including Spectronaut's directDIA, DIA-Umpire, DIA-MSFragger, and in silico-predicted library for analysis of phosphoproteomics SWATH, DIA, and diaPASEF data as well as ubiquitinomics diaPASEF data. Spectronaut's directDIA shows the highest sensitivity for phosphopeptide detection not only in synthetic phosphopeptide samples but also in phosphoproteomics SWATH-MS and DIA data from real biological samples, when compared to the other three library-free strategies. For phosphoproteomics diaPASEF data, Spectronaut's directDIA and the in silico-predicted library based on DIA-NN identify almost the same number of phosphopeptides as a project-specific DDA spectral library. However, only about 30% of the total phosphopeptides are commonly identified, suggesting that the library-free strategies for phospho-diaPASEF data need further improvement in terms of sensitivity. For ubiquitinomics diaPASEF data, the in silico-predicted library performs the best among the four workflows and detects ∼50% more K-GG peptides than a project-specific DDA spectral library. Our results demonstrate that Spectronaut's directDIA is suitable for the analysis of phosphoproteomics SWATH-MS and DIA MS data, while the in silico-predicted library based on DIA-NN shows substantial advantages for ubiquitinomics diaPASEF MS data.


Assuntos
Fosfopeptídeos , Proteômica , Proteômica/métodos , Espectrometria de Massas/métodos , Proteoma/análise
9.
ACS Sens ; 8(3): 1328-1338, 2023 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-36883832

RESUMO

Timely screening of lung cancer represents a challenging task for early diagnosis and treatment, which calls for reliable, low-cost, and noninvasive detection tools. One type of promising tools for early-stage cancer detection is breath analyzers or sensors that detect breath volatile organic compounds (VOCs) as biomarkers in exhaled breaths. However, a major challenge is the lack of effective integration of the different sensor system components toward the desired portability, sensitivity, selectivity, and durability for many of the current breath sensors. In this report, we demonstrate herein a portable and wireless breath sensor testing system integrated with sensor electronics, breath sampling, data processing, and sensor arrays derived from nanoparticle-structured chemiresistive sensing interfaces for detection of VOCs relevant to lung cancer biomarkers in human breaths. In addition to showing the sensor viability for the targeted application by theoretical simulations of chemiresistive sensor array responses to the simulated VOCs in human breaths, the sensor system was tested experimentally with different combinations of VOCs and human breath samples spiked with lung cancer-specific VOCs. The sensor array exhibits high sensitivity to lung cancer VOC biomarkers and mixtures, with a limit of detection as low as 6 ppb. The results from testing the sensor array system in detecting breath samples with simulated lung cancer VOC constituents have demonstrated an excellent recognition rate in discriminating healthy human breath samples and those with lung cancer VOCs. The recognition statistics were analyzed, showing the potential viability and optimization toward achieving the desired sensitivity, selectivity, and accuracy in the breath screening of lung cancer.


Assuntos
Neoplasias Pulmonares , Nanoestruturas , Compostos Orgânicos Voláteis , Humanos , Neoplasias Pulmonares/diagnóstico , Biomarcadores Tumorais , Detecção Precoce de Câncer/métodos
10.
Int J Mol Sci ; 24(4)2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36834473

RESUMO

Rind color is an economically important agronomic trait in eggplant that impacts consumer preferences. In this study, bulked segregant analysis and competitive allele-specific PCR were employed to identify the candidate gene for eggplant rind color through constructing a 2794 F2 population generated from a cross between "BL01" (green pericarp) and "B1" (white pericarp). Genetic analysis of rind color revealed that a single dominant gene controls green color of eggplant peel. Pigment content measurement and cytological observations demonstrated that chlorophyll content and chloroplast number in BL01 were higher than in B1. A candidate gene (EGP19168.1) was fine-mapped to a 20.36 Kb interval on chromosome 8, which was predicted to encode the two-component response regulator-like protein Arabidopsis pseudo-response regulator2 (APRR2). Subsequently, allelic sequence analysis revealed that a SNP deletion (ACT→AT) in white-skinned eggplant led to a premature termination codon. Genotypic validation of 113 breeding lines using the Indel marker closely linked to SmAPRR2 could predict the skin color (green/white) trait with an accuracy of 92.9%. This study will be valuable for molecular marker-assisted selection in eggplant breeding and provides theoretical foundation for analyzing the formation mechanism of eggplant peel color.


Assuntos
Solanum melongena , Mapeamento Cromossômico , Solanum melongena/genética , Melhoramento Vegetal , Fenótipo
11.
J Agric Food Chem ; 71(5): 2290-2300, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36706242

RESUMO

Nitrogen (N) application increases wheat yield and protein content and affects the nutritional quality of the grain. Analysis of N use efficiency revealed that N uptake efficiency is a key factor affecting protein content. Two wheat lines with significant differences in protein content were used to investigate the response of differential accumulation of metabolites to N levels and the spatial variation pattern of metabolites related to nutritional quality in wheat grains using widely targeted metabolomics analysis. The results showed that amino acids, nucleic acids, and phytohormones and their derivatives and glycolytic processes are the crucial factors affecting protein content in two wheat lines. Amino acids and derivatives, lipids, and flavonoids are the main contributors to metabolite spatial variation of grains, which were interactively regulated by nitrogen and genotypes. N application significantly increased the relative accumulation of beneficial bioactive substances in the inner layer (P3 to P5), but excessive N application may inhibit this effect and lead to poor nutritional quality.


Assuntos
Farinha , Triticum , Triticum/química , Nitrogênio/metabolismo , Metabolômica/métodos , Aminoácidos/metabolismo , Grão Comestível/química
12.
Proteomics ; 23(1): e2200204, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36408942

RESUMO

Exosomes derived from mesenchymal stem cells (MSCs) have been used for cancer treatment, however, an in-depth analysis of the exosomal proteomes is lacking. In this manuscript, we use the diaPASEF (parallel accumulation serial fragmentation combined with the data-independent acquisition) method to quantify exosomes derived from human umbilical cord mesenchymal stem cells (UCMSCs) and rat bone marrow stem cells (BMSCs), resulting in identification of 4200 human proteins and 5362 rat proteins. Comparison of human exosomal proteins and total cellular proteins reveals that some proteins exist in the exosomes exclusively that can be served as potential markers for exosomes. Quantitative proteomic analysis of exosomes from different passages of BMSCs shows that the proteins involved in TGF-ß signaling pathway are regulated in abundance, which could be markers for the therapeutic ability of BMSC exosomes. Collectively, the data presented by this study can be a resource for further study of exosome research.


Assuntos
Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Ratos , Humanos , Animais , Exossomos/metabolismo , Proteômica , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical/metabolismo , Células da Medula Óssea/metabolismo , MicroRNAs/metabolismo
13.
Faraday Discuss ; 242(0): 429-442, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36173024

RESUMO

Activity, cost, and durability are the trinity of catalysis research for the electrochemical oxygen reduction reaction (ORR). While studies towards increasing activity and reducing cost of ORR catalysts have been carried out extensively, much effort is needed in durability investigation of highly active ORR catalysts. In this work, we examined the stability of a trimetallic PtPdCu catalyst that has demonstrated high activity and incredible durability during ORR using density functional theory (DFT) based computations. Specifically, we studied the processes of dissolution/deposition and diffusion between the surface and inner layer of Cu species of Pt20Pd20Cu60 catalysts at electrode potentials up to 1.2 V to understand their role towards stabilizing Pt20Pd20Cu60 catalysts. The results show there is a dynamic Cu surface composition range that is dictated by the interplay of the four processes, dissolution, deposition, diffusion from the surface to inner layer, and diffusion from the inner layer to the surface of Cu species, in the stability and observed oscillation of lattice constants of Cu-rich PtPdCu nanoalloys.

14.
Nat Commun ; 13(1): 7465, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463257

RESUMO

Morphogenesis of many protozoans depends on a polarized establishment of cortical cytoskeleton containing the subpellicular microtubules (SPMTs), which are apically nucleated and anchored by the apical polar ring (APR). In malaria parasite Plasmodium, APR emerges in the host-invading stages, including the ookinete for mosquito infection. So far, the fine structure and molecular components of APR as well as the underlying mechanism of APR-mediated apical positioning of SPMTs are largely unknown. Here, we resolve an unprecedented APR structure composed of a top ring plus approximate 60 radiating spines. We report an APR-localizing and SPMT-binding protein APR2. APR2 disruption impairs ookinete morphogenesis and gliding motility, leading to Plasmodium transmission failure in mosquitoes. The APR2-deficient ookinetes display defective apical anchorage of APR and SPMT due to the impaired integrity of APR. Using protein proximity labeling, we obtain a Plasmodium ookinete APR proteome and validate ten undescribed APR proteins. Among them, APRp2 and APRp4 directly interact with APR2 and also mediate the apical anchorage of SPMTs. This study sheds light on the molecular basis of APR in the organization of Plasmodium ookinete SPMTs.


Assuntos
Culicidae , Malária , Animais , Citoesqueleto , Microtúbulos
15.
Front Pharmacol ; 13: 949566, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386184

RESUMO

Non-small cell lung cancer (NSCLC) is one of the most common malignant tumors worldwide. Clinical success is suboptimal owing to late diagnosis, limited treatment options, high recurrence rates, and the development of drug resistance. MicroRNAs (miRNAs), a range of small endogenous non-coding RNAs that are 22 nucleotides in length, have emerged as one of the most important players in cancer initiation and progression in recent decades. Current evidence has revealed the pivotal roles of miRNAs in regulating cell proliferation, migration, invasion, and metastasis in NSCLC. Recently, several studies have demonstrated that miRNAs are strongly associated with resistance to anti-cancer drugs, ranging from traditional chemotherapeutic and immunotherapy drugs to anti-vascular drugs, and even during radiotherapy. In this review, we briefly introduce the mechanism of miRNA dysregulation and resistance to anti-tumor therapy in NSCLC, and summarize the role of miRNAs in the malignant process of NSCLC. We then discuss studies of resistance-related miRNAs in chemotherapy, radiotherapy, targeted therapy, immunotherapy, and anti-vascular therapy in NSCLC. Finally, we will explore the application prospects of miRNA, an emerging small molecule, for future anti-tumor therapy. This review is the first to summarize the latest research progress on miRNAs in anti-cancer drug resistance based on drug classification, and to discuss their potential clinical applications.

16.
Front Surg ; 9: 953989, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36117809

RESUMO

Introduction: Primary pleural squamous cell carcinoma (PPSCC) is a sporadic disease that is rarely reported in the literature. Due to its low incidence, the pathogenesis of PPSCC is unknown. Case summary: We report a case of a 68-year-old male with PPSCC and sizable pulmonary bullae. Two months after complete resection of both lesions, a total dose of 50 Gy radiotherapy was administered over the operative field. After more than a year of follow-up, the patient is in steady condition without any sign of recurrence. Conclusion: Since PPSCC is rarely reported, our case proposed that complete surgical resection combined with radiotherapy may be a promising therapeutic approach.

17.
Elife ; 112022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35775739

RESUMO

Malaria is caused by infection of the erythrocytes by the parasites Plasmodium. Inside the erythrocytes, the parasites multiply via schizogony, an unconventional cell division mode. The inner membrane complex (IMC), an organelle located beneath the parasite plasma membrane, serving as the platform for protein anchorage, is essential for schizogony. So far, the complete repertoire of IMC proteins and their localization determinants remain unclear. Here we used biotin ligase (TurboID)-based proximity labeling to compile the proteome of the schizont IMC of the rodent malaria parasite Plasmodium yoelii. In total, 300 TurboID-interacting proteins were identified. 18 of 21 selected candidates were confirmed to localize in the IMC, indicating good reliability. In light of the existing palmitome of Plasmodium falciparum, 83 proteins of the P. yoelii IMC proteome are potentially palmitoylated. We further identified DHHC2 as the major resident palmitoyl-acyl-transferase of the IMC. Depletion of DHHC2 led to defective schizont segmentation and growth arrest both in vitro and in vivo. DHHC2 was found to palmitoylate two critical IMC proteins CDPK1 and GAP45 for their IMC localization. In summary, this study reports an inventory of new IMC proteins and demonstrates a central role of DHHC2 in governing the IMC localization of proteins during the schizont development.


Assuntos
Malária , Parasitos , Animais , Eritrócitos/parasitologia , Lipoilação , Malária/parasitologia , Parasitos/metabolismo , Plasmodium falciparum/fisiologia , Proteoma/metabolismo , Proteômica , Proteínas de Protozoários/metabolismo , Reprodutibilidade dos Testes , Esquizontes
19.
Langmuir ; 38(18): 5633-5644, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35475615

RESUMO

There is an increasing need to reduce the silver content in silver-based inks or pastes and achieve low-temperature sintering for scalable and low-cost production of printed wearable electronics. This need depends on the ability to control the metal composition and the surface properties of the nanoinks. Alloying silver with copper provides a pathway for meeting the need in terms of cost reduction, but little is known about the composition controllability and the low-temperature sintering capability. We report herein a scalable wet chemical synthesis of bimetallic silver-copper alloy nanoinks with room temperature sintering properties. The bimetallic alloy nanoparticles with a controllable composition can be formulated as stable nanoinks. The nanoinks printed on paper substrates are shown to sinter under room temperature. In addition to composition dependence, the results reveal an intriguing dependence of sintering on humidity above the printed nanoink films. These findings are assessed based on theoretical simulation of the sintering processes via surface-mediated sintering and interparticle necking mechanisms in terms of nanoscale adsorption, adhesion and diffusion, and surface free energies. Implications of the findings for room temperature fabrication of wearable sensors are also discussed.


Assuntos
Nanopartículas Metálicas , Prata , Ligas , Cobre/química , Nanopartículas Metálicas/química , Prata/química , Temperatura
20.
Sensors (Basel) ; 22(7)2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35408393

RESUMO

This paper describes the design of a low-current, multichannel, handheld electronic device integrated with nanostructured chemiresistor sensor arrays. A key design feature of the electronic circuit board is its low excitation current for achieving optimal performance with the arrays. The electronics can rapidly acquire the resistances for different sensors, not only spanning several orders of magnitude, but also as high as several hundreds of megaohms. The device tested is designed using a chemiresistor array with nanostructured sensing films prepared by molecularly-mediated assemblies of gold nanoparticles for detection. The low-current, wide-range, and auto-locking capabilities, along with the effective coupling with the nanostructured chemiresistor arrays, meet the desired performances of a low excitation current and low power consumption, and also address the potential instability of the sensors in a complex sensing environment. The results are promising for potential applications of the device as a portable sensor for the point-of-need monitoring of air quality and as a biosensor for point-of-care human breath screening for disease biomarkers.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Eletrônica , Ouro , Humanos
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