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1.
Nat Commun ; 15(1): 5785, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987244

RESUMO

Chloroaluminate ionic liquids selectively transform (waste) polyolefins into gasoline-range alkanes through tandem cracking-alkylation at temperatures below 100 °C. Further improvement of this process necessitates a deep understanding of the nature of the catalytically active species and the correlated performance in the catalyzing critical reactions for the tandem polyolefin deconstruction with isoalkanes at low temperatures. Here, we address this requirement by determining the nuclearity of the chloroaluminate ions and their interactions with reaction intermediates, combining in situ 27Al magic-angle spinning nuclear magnetic resonance spectroscopy, in situ Raman spectroscopy, Al K-edge X-ray absorption near edge structure spectroscopy, and catalytic activity measurement. Cracking and alkylation are facilitated by carbenium ions initiated by AlCl3-tert-butyl chloride (TBC) adducts, which are formed by the dissociation of Al2Cl7- in the presence of TBC. The carbenium ions activate the alkane polymer strands and advance the alkylation cycle through multiple hydride transfer reactions. In situ 1H NMR and operando infrared spectroscopy demonstrate that the cracking and alkylation processes occur synchronously; alkenes formed during cracking are rapidly incorporated into the carbenium ion-mediated alkylation cycle. The conclusions are further supported by ab initio molecular dynamics simulations coupled with an enhanced sampling method, and model experiments using n-hexadecane as a feed.

2.
Angew Chem Int Ed Engl ; 63(17): e202319580, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38433092

RESUMO

Transforming polyolefin waste into liquid alkanes through tandem cracking-alkylation reactions catalyzed by Lewis-acid chlorides offers an efficient route for single-step plastic upcycling. Lewis acids in dichloromethane establish a polar environment that stabilizes carbenium ion intermediates and catalyzes hydride transfer, enabling breaking of polyethylene C-C bonds and forming C-C bonds in alkylation. Here, we show that efficient and selective deconstruction of low-density polyethylene (LDPE) to liquid alkanes is achieved with anhydrous aluminum chloride (AlCl3) and gallium chloride (GaCl3). Already at 60 °C, complete LDPE conversion was achieved, while maintaining the selectivity for gasoline-range liquid alkanes over 70 %. AlCl3 showed an exceptional conversion rate of 5000 g L D P E m o l c a t - 1 h - 1 ${{{\rm g}}_{{\rm L}{\rm D}{\rm P}{\rm E}}{{\rm \ }{\rm m}{\rm o}{\rm l}}_{{\rm c}{\rm a}{\rm t}}^{-1}{{\rm \ }{\rm h}}^{-1}}$ , surpassing other Lewis acid catalysts by two orders of magnitude. Through kinetic and mechanistic studies, we show that the rates of LDPE conversion do not correlate directly with the intrinsic strength of the Lewis acids or steric constraints that may limit the polymer to access the Lewis acid sites. Instead, the rates for the tandem processes of cracking and alkylation are primarily governed by the rates of initiation of carbenium ions and the subsequent intermolecular hydride transfer. Both jointly control the relative rates of cracking and alkylation, thereby determining the overall conversion and selectivity.

3.
Microsyst Nanoeng ; 10: 23, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38317693

RESUMO

Extracellular vesicles (EVs) have been identified as promising biomarkers for the noninvasive diagnosis of various diseases. However, challenges in separating EVs from soluble proteins have resulted in variable EV recovery rates and low purities. Here, we report a high-yield ( > 90%) and rapid ( < 10 min) EV isolation method called FLocculation via Orbital Acoustic Trapping (FLOAT). The FLOAT approach utilizes an acoustofluidic droplet centrifuge to rotate and controllably heat liquid droplets. By adding a thermoresponsive polymer flocculant, nanoparticles as small as 20 nm can be rapidly and selectively concentrated at the center of the droplet. We demonstrate the ability of FLOAT to separate urinary EVs from the highly abundant Tamm-Horsfall protein, addressing a significant obstacle in the development of EV-based liquid biopsies. Due to its high-yield nature, FLOAT reduces biofluid starting volume requirements by a factor of 100 (from 20 mL to 200 µL), demonstrating its promising potential in point-of-care diagnostics.

4.
Chem Commun (Camb) ; 60(13): 1747-1750, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38247444

RESUMO

Dual thermo- and light-responsive water-soluble copolymers that respond to exclusively non-invasive triggers are obtained by functionalising poly(N,N-dimethylacrylamide) with arylazopyrazole side chains. The light-induced E-Z (trans-Z) photo isomerisation of these dyes provides an exceptionally effective photo-switch, which can reversibly shift the LCST-type phase transition temperatures by almost 25 K.

5.
Circ Res ; 133(9): 739-757, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37750320

RESUMO

BACKGROUND: In developmental and pathological tissues, nascent vessel networks generated by angiogenesis require further pruning/regression to delete nonfunctional endothelial cells (ECs) by apoptosis and migration. Mechanisms underlying EC apoptosis during vessel pruning remain elusive. TMEM215 (transmembrane protein 215) is an endoplasmic reticulum-located, 2-pass transmembrane protein. We have previously demonstrated that TMEM215 knockdown in ECs leads to cell death, but its physiological function and mechanism are unclear. METHODS: We characterized the role and mechanism of TMEM215 in EC apoptosis using human umbilical vein endothelial cells by identifying its interacting proteins with immunoprecipitation-mass spectrometry. The physiological function of TMEM215 in ECs was assessed by establishing a conditional knockout mouse strain. The role of TMEM215 in pathological angiogenesis was evaluated by tumor and choroidal neovascularization models. We also tried to evaluate its translational value by delivering a Tmem215 small interfering RNA (siRNA) using nanoparticles in vivo. RESULTS: TMEM215 knockdown in ECs induced apoptotic cell death. We identified the chaperone BiP as a binding partner of TMEM215, and TMEM215 forms a complex with and facilitates the interaction of BiP (binding immunoglobin protein) with the BH (BCL-2 [B-cell lymphoma 2] homology) 3-only proapoptotic protein BIK (BCL-2 interacting killer). TMEM215 knockdown triggered apoptosis in a BIK-dependent way and was abrogated by BCL-2. Notably, TMEM215 knockdown increased the number and diminished the distance of mitochondria-associated endoplasmic reticulum membranes and increased mitochondrial calcium influx. Inhibiting mitochondrial calcium influx by blocking the IP3R (inositol 1,4,5-trisphosphate receptor) or MCU (mitochondrial calcium uniporter) abrogated TMEM215 knockdown-induced apoptosis. TMEM215 expression in ECs was induced by physiological laminar shear stress via EZH2 downregulation. In EC-specific Tmem215 knockout mice, induced Tmem215 depletion impaired the regression of retinal vasculature characterized by reduced vessel density, increased empty basement membrane sleeves, and increased EC apoptosis. Moreover, EC-specific Tmem215 ablation inhibited tumor growth with disrupted vasculature. However, Tmem215 ablation in adult mice attenuated lung metastasis, consistent with reduced Vcam1 expression. Administration of nanoparticles carrying Tmem215 siRNA also inhibited tumor growth and choroidal neovascularization injury. CONCLUSIONS: TMEM215, which is induced by blood flow-derived shear stress via downregulating EZH2, protects ECs from BIK-triggered mitochondrial apoptosis mediated by calcium influx through mitochondria-associated ER membranes during vessel pruning, thus providing a novel target for antiangiogenic therapy.

6.
J Occup Environ Med ; 65(12): 1008-1016, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37621038

RESUMO

OBJECTIVE: To investigate the association among managers' attitudes toward subordinates with common mental disorders (CMDs), self-confidence in supporting these subordinates, and managerial preventive actions (MPAs). METHODS: A cross-sectional study was conducted among Swedish managers (n = 2988) and two types of MPAs: reviewing assignments and work situation (MPA-review), and talking about CMD at the workplace (MPA-talk). Binary logistic regression models were applied and adjusted for individual and organizational covariates. RESULTS: Managers with negative attitudes toward subordinates with CMD were less likely to have done both MPAs. Managers with higher self-confidence in supporting these subordinates were more likely to have done both MPAs compared with managers with lower self-confidence. CONCLUSIONS: Managerial negative attitudes toward CMD and self-confidence in supporting subordinates with CMD have a role in MPAs and should be addressed in manager training programs to encourage preventive actions.


Assuntos
Transtornos Mentais , Humanos , Estudos Transversais , Suécia , Transtornos Mentais/prevenção & controle , Local de Trabalho , Atitude
7.
J Vasc Res ; 60(4): 234-244, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37643584

RESUMO

INTRODUCTION: Culturing cerebrovascular smooth muscle cells (CVSMCs) in vitro can provide a model for studying many cerebrovascular diseases. This study describes a convenient and efficient method to obtain mouse CVSMCs by enzyme digestion. METHODS: Mouse circle of Willis was isolated, digested, and cultured with platelet-derived growth factor-BB (PDGF-BB) to promote CVSMC growth, and CVSMCs were identified by morphology, immunofluorescence analysis, and flow cytometry. The effect of PDGF-BB on vascular smooth muscle cell (VSMC) proliferation was evaluated by cell counting kit (CCK)-8 assay, morphological observations, Western blotting, and flow cytometry. RESULTS: CVSMCs cultured in a PDGF-BB-free culture medium had a typical peak-to-valley growth pattern after approximately 14 days. Immunofluorescence staining and flow cytometry detected strong positive expression of the cell type-specific markers alpha-smooth muscle actin (α-SMA), smooth muscle myosin heavy chain 11 (SMMHC), smooth muscle protein 22 (SM22), calponin, and desmin. In the CCK-8 assay and Western blotting, cells incubated with PDGF-BB had significantly enhanced proliferation compared to those without PDGF-BB. CONCLUSION: We obtained highly purified VSMCs from the mouse circle of Willis using simple methods, providing experimental materials for studying the pathogenesis and treatment of neurovascular diseases in vitro. Moreover, the experimental efficiency improved with PDGF-BB, shortening the cell cultivation period.


Assuntos
Círculo Arterial do Cérebro , Músculo Liso Vascular , Animais , Camundongos , Becaplermina/farmacologia , Becaplermina/metabolismo , Proteínas Proto-Oncogênicas c-sis/farmacologia , Proteínas Proto-Oncogênicas c-sis/metabolismo , Músculo Liso Vascular/metabolismo , Células Cultivadas , Proliferação de Células , Miócitos de Músculo Liso/metabolismo , Movimento Celular
8.
J Clin Invest ; 133(20)2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37607001

RESUMO

Human cancers induce a chaotic, dysfunctional vasculature that promotes tumor growth and blunts most current therapies; however, the mechanisms underlying the induction of a dysfunctional vasculature have been unclear. Here, we show that split end (SPEN), a transcription repressor, coordinates rRNA synthesis in endothelial cells (ECs) and is required for physiological and tumor angiogenesis. SPEN deficiency attenuated EC proliferation and blunted retinal angiogenesis, which was attributed to p53 activation. Furthermore, SPEN knockdown activated p53 by upregulating noncoding promoter RNA (pRNA), which represses rRNA transcription and triggers p53-mediated nucleolar stress. In human cancer biopsies, a low endothelial SPEN level correlated with extended overall survival. In mice, endothelial SPEN deficiency compromised rRNA expression and repressed tumor growth and metastasis by normalizing tumor vessels, and this was abrogated by p53 haploinsufficiency. rRNA gene transcription is driven by RNA polymerase I (RNPI). We found that CX-5461, an RNPI inhibitor, recapitulated the effect of Spen ablation on tumor vessel normalization and combining CX-5461 with cisplatin substantially improved the efficacy of treating tumors in mice. Together, these results demonstrate that SPEN is required for angiogenesis by repressing pRNA to enable rRNA gene transcription and ribosomal biogenesis and that RNPI represents a target for tumor vessel normalization therapy of cancer.


Assuntos
Neoplasias , Proteína Supressora de Tumor p53 , Humanos , Camundongos , Animais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Células Endoteliais/metabolismo , Transcrição Gênica , RNA Polimerase I/genética , Neoplasias/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a RNA/genética
9.
Life Sci ; 326: 121828, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37270171

RESUMO

AIM: Under various pathological conditions such as cancer, vascular smooth muscle cells (vSMCs) transit their contractile phenotype into phenotype(s) characterized by proliferation and secretion, a process called vSMC phenotypic transition (vSMC-PT). Notch signaling regulates vSMC development and vSMC-PT. This study aims to elucidate how the Notch signal is regulated. MAIN METHODS: Gene-modified mice with a SM22α-CreERT2 transgene were generated to activate/block Notch signaling in vSMCs. Primary vSMCs and MOVAS cells were cultured in vitro. RNA-seq, qRT-PCR and Western blotting were used to evaluated gene expression level. EdU incorporation, Transwell and collagen gel contraction assays were conducted to determine the proliferation, migration and contraction, respectively. KEY FINDINGS: Notch activation upregulated, while Notch blockade downregulated, miR-342-5p and its host gene Evl in vSMCs. However, miR-342-5p overexpression promoted vSMC-PT as shown by altered gene expression profile, increased migration and proliferation, and decreased contraction, while miR-342-5p blockade exhibited the opposite effects. Moreover, miR-342-5p overexpression significantly suppressed Notch signaling, and Notch activation partially abolished miR-342-5p-induced vSMC-PT. Mechanically, miR-342-5p directly targeted FOXO3, and FOXO3 overexpression rescued miR-342-5p-induced Notch repression and vSMC-PT. In a simulated tumor microenvironment, miR-342-5p was upregulated by tumor cell-derived conditional medium (TCM), and miR-342-5p blockade abrogated TCM-induced vSMC-PT. Meanwhile, conditional medium from miR-342-5p-overexpressing vSMCs significantly enhanced tumor cell proliferation, while miR-342-5p blockade had the opposite effects. Consistently, in a co-inoculation tumor model, miR-342-5p blockade in vSMCs significantly delayed tumor growth. SIGNIFICANCE: miR-342-5p promotes vSMC-PT through a negative-feedback regulation of Notch signaling via downregulating FOXO3, which could be a potential target for cancer therapy.


Assuntos
MicroRNAs , Camundongos , Animais , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , Proliferação de Células/genética , Movimento Celular/genética , Retroalimentação , Fenótipo , Miócitos de Músculo Liso/metabolismo , Células Cultivadas
10.
Mol Ther Nucleic Acids ; 32: 343-358, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37128275

RESUMO

During vascular development, endothelial cells (ECs) undergo arterialization in response to genetic programs and shear stress-triggered mechanotransduction, forming a stable vasculature. Although the Notch receptor is known to sense shear stress and promote EC arterialization, its downstream mechanisms remain unclear. In this study, the Notch downstream miR-342-5p was found to respond to shear stress and promote EC arterialization. Shear stress upregulated miR-342-5p in a Notch-dependent manner in human umbilical vein endothelial cells (HUVECs). miR-342-5p overexpression upregulated the shear stress-associated transcriptomic signature. Moreover, miR-342-5p upregulated arterial markers and promoted EC arterialization in a Matrigel plug assay and retinal angiogenesis model. In contrast, miR-342-5p knockdown downregulated arterial markers, compromised retinal arterialization, and partially abrogated shear stress and Notch activation-induced arterial marker upregulation. Mechanistically, miR-342-5p overexpression suppressed MYC to repress EC proliferation and promote arterialization, achieved by promoting MYC protein degradation by targeting the EYA3. Consistently, EYA3 overexpression rescued miR-342-5p-mediated MYC downregulation and EC arterialization. In vivo, miR-342-5p expression was notably decreased in the ligated artery in a hindlimb ischemia model, and an intramuscular injection of miR-342-5p promoted EC arterialization and improved perfusion. In summary, miR-342-5p, a mechano-miR, mediates the effects of shear stress-activated Notch on EC arterialization and is a potential therapeutic target for ischemic diseases.

11.
Nanotechnology ; 34(28)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37059090

RESUMO

The anisotropic transport properties of gallium telluride (GaTe) have been reported by several experiments, giving rise to many debates recently. The anisotropic electronic band structure of GaTe shows the extreme difference between the flat band and tilted band in two distinct directions,Γ¯-X¯andΓ¯-Y¯, and which we called as the mixed flat-tilted band (MFTB). Focusing on such two directions, the relaxation of photo-generated carriers has been studied using the non-adiabatic molecular dynamics (NAMD) method to investigate the anisotropic behavior of ultrafast dynamics. The results show that the relaxation lifetime is different in flat band direction and tilted band direction, which is evidence for the existence of anisotropic behavior of the ultrafast dynamic, and such anisotropic behavior comes from the different intensities of electron-phonon coupling of the flat band and tilted band. Furthermore, the ultrafast dynamic behavior is found to be affected strongly by spin-orbit coupling (SOC) and such anisotropic behavior of the ultrafast dynamic can be reversed by SOC. The tunable anisotropic ultrafast dynamic behavior of GaTe is expected to be detected in ultrafast spectroscopy experiments and it may provide a tunable application in nanodevice design. The results may also provide a reference for the investigation of MFTB semiconductors.

12.
Biochem Biophys Res Commun ; 642: 128-136, 2023 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-36577249

RESUMO

Liver organogenesis is a complex process. Although many signaling pathways and key factors have been identified during liver development, little is known about the regulation of late liver development, especially liver maturation. As a transcriptional repressor, SPEN has been demonstrated to interact with lncRNAs and transcription factors to participate in X chromosome inactivation, neural development, and lymphocyte differentiation. General disruption of SPEN results in embryonic lethality accompanied by hampered liver development in mice. However, the function of SPEN in embryonic liver development has not been reported. In this study, we demonstrate that SPEN is required for hepatocyte maturation using hepatocyte-specific disruption of SPEN with albumin-Cre-mediated knockout. SPEN expression was upregulated in hepatocytes along with liver development in mice. The deletion of the SPEN gene repressed hepatic maturation, mainly by a decrease in hepatic metabolic function and disruption of hepatocyte zonation. Additional experiments revealed that transcription factors which control hepatocyte maturation were strongly downregulated in SPEN-deficient hepatocytes, especially Hnf4α. Furthermore, restoration of Hnf4α levels partially rescued the immature state of hepatocytes caused by SPEN gene deletion. Taken together, these results reveal an unexpected role of SPEN in liver maturation.


Assuntos
Fator 4 Nuclear de Hepatócito , Hepatócitos , Camundongos , Animais , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a DNA/metabolismo
13.
Sci Adv ; 8(47): eade0640, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36417505

RESUMO

High-precision isolation of small extracellular vesicles (sEVs) from biofluids is essential toward developing next-generation liquid biopsies and regenerative therapies. However, current methods of sEV separation require specialized equipment and time-consuming protocols and have difficulties producing highly pure subpopulations of sEVs. Here, we present Acoustic Nanoscale Separation via Wave-pillar Excitation Resonance (ANSWER), which allows single-step, rapid (<10 min), high-purity (>96% small exosomes, >80% exomeres) fractionation of sEV subpopulations from biofluids without the need for any sample preprocessing. Particles are iteratively deflected in a size-selective manner via an excitation resonance. This previously unidentified phenomenon generates patterns of virtual, tunable, pillar-like acoustic field in a fluid using surface acoustic waves. Highly precise sEV fractionation without the need for sample preprocessing or complex nanofabrication methods has been demonstrated using ANSWER, showing potential as a powerful tool that will enable more in-depth studies into the complexity, heterogeneity, and functionality of sEV subpopulations.

14.
Nat Commun ; 13(1): 3459, 2022 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710904

RESUMO

Newly developed acoustic technologies are playing a transformational role in life science and biomedical applications ranging from the activation and inactivation of mechanosensitive ion channels for fundamental physiological processes to the development of contact-free, precise biofabrication protocols for tissue engineering and large-scale manufacturing of organoids. Here, we provide our perspective on the development of future acoustic technologies and their promise in addressing critical challenges in biomedicine.


Assuntos
Acústica , Som , Atenção à Saúde , Organoides , Engenharia Tecidual
15.
Microsyst Nanoeng ; 8: 45, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35498337

RESUMO

Nanocarrier and exosome encapsulation has been found to significantly increase the efficacy of targeted drug delivery while also minimizing unwanted side effects. However, the development of exosome-encapsulated drug nanocarriers is limited by low drug loading efficiencies and/or complex, time-consuming drug loading processes. Herein, we have developed an acoustofluidic device that simultaneously performs both drug loading and exosome encapsulation. By synergistically leveraging the acoustic radiation force, acoustic microstreaming, and shear stresses in a rotating droplet, the concentration, and fusion of exosomes, drugs, and porous silica nanoparticles is achieved. The final product consists of drug-loaded silica nanocarriers that are encased within an exosomal membrane. The drug loading efficiency is significantly improved, with nearly 30% of the free drug (e.g., doxorubicin) molecules loaded into the nanocarriers. Furthermore, this acoustofluidic drug loading system circumvents the need for complex chemical modification, allowing drug loading and encapsulation to be completed within a matter of minutes. These exosome-encapsulated nanocarriers exhibit excellent efficiency in intracellular transport and are capable of significantly inhibiting tumor cell proliferation. By utilizing physical forces to rapidly generate hybrid nanocarriers, this acoustofluidic drug loading platform wields the potential to significantly impact innovation in both drug delivery research and applications.

16.
Sci Adv ; 8(13): eabm2592, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35363512

RESUMO

Acoustic black holes offer superior capabilities for slowing down and trapping acoustic waves for various applications such as metastructures, energy harvesting, and vibration and noise control. However, no studies have considered the linear and nonlinear effects of acoustic black holes on micro/nanoparticles in fluids. This study presents acoustofluidic black holes (AFBHs) that leverage controlled interactions between AFBH-trapped acoustic wave energy and particles in droplets to enable versatile particle manipulation functionalities, such as translation, concentration, and patterning of particles. We investigated the AFBH-enabled wave energy trapping and wavelength shrinking effects, as well as the trapped wave energy-induced acoustic radiation forces on particles and acoustic streaming in droplets. This study not only fills the gap between the emerging fields of acoustofluidics and acoustic black holes but also leads to a class of AFBH-based in-droplet particle manipulation toolsets with great potential for many applications, such as biosensing, point-of-care testing, and drug screening.

17.
Biosens Bioelectron ; 196: 113730, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34736099

RESUMO

Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative brain disorder that affects tens of millions of older adults worldwide and has significant economic and societal impacts. Despite its prevalence and severity, early diagnosis of AD remains a considerable challenge. Here we report an integrated acoustofluidics-based diagnostic system (ADx), which combines triple functions of acoustics, microfluidics, and orthogonal biosensors for clinically accurate, sensitive, and rapid detection of AD biomarkers from human plasma. We design and fabricate a surface acoustic wave-based acoustofluidic separation device to isolate and purify AD biomarkers to increase the signal-to-noise ratio. Multimodal biosensors within the integrated ADx are fabricated by in-situ patterning of the ZnO nanorod array and deposition of Ag nanoparticles onto the ZnO nanorods for surface-enhanced Raman scattering (SERS) and electrochemical immunosensors. We obtain the label-free detections of SERS and electrochemical immunoassay of clinical plasma samples from AD patients and healthy controls with high sensitivity and specificity. We believe that this efficient integration provides promising solutions for the early diagnosis of AD.


Assuntos
Doença de Alzheimer , Técnicas Biossensoriais , Nanopartículas Metálicas , Idoso , Doença de Alzheimer/diagnóstico , Humanos , Imunoensaio , Prata , Análise Espectral Raman
18.
Nat Commun ; 12(1): 3844, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34158489

RESUMO

The ability to precisely manipulate nano-objects on a large scale can enable the fabrication of materials and devices with tunable optical, electromagnetic, and mechanical properties. However, the dynamic, parallel manipulation of nanoscale colloids and materials remains a significant challenge. Here, we demonstrate acoustoelectronic nanotweezers, which combine the precision and robustness afforded by electronic tweezers with versatility and large-field dynamic control granted by acoustic tweezing techniques, to enable the massively parallel manipulation of sub-100 nm objects with excellent versatility and controllability. Using this approach, we demonstrated the complex patterning of various nanoparticles (e.g., DNAs, exosomes, ~3 nm graphene flakes, ~6 nm quantum dots, ~3.5 nm proteins, and ~1.4 nm dextran), fabricated macroscopic materials with nano-textures, and performed high-resolution, single nanoparticle manipulation. Various nanomanipulation functions, including transportation, concentration, orientation, pattern-overlaying, and sorting, have also been achieved using a simple device configuration. Altogether, acoustoelectronic nanotweezers overcome existing limitations in nano-manipulation and hold great potential for a variety of applications in the fields of electronics, optics, condensed matter physics, metamaterials, and biomedicine.


Assuntos
Eletrônica/métodos , Nanoestruturas/química , Nanotecnologia/métodos , Pinças Ópticas , Acústica , Coloides/química , DNA/química , Exossomos/química , Nanopartículas Metálicas/química , Nanotubos de Carbono , Tamanho da Partícula , Reprodutibilidade dos Testes
19.
Acta Crystallogr C Struct Chem ; 77(Pt 6): 291-298, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34089253

RESUMO

Multidentate carboxylate ligands have been widely used in the construction of metal-organic frameworks (MOFs) owing to the rich variety of their coordination modes, which can lead to crystalline products with interesting structures and properties. Two new main-group MOFs, namely, poly[[di-µ-aqua-diaqua(dimethylformamide)[µ7-5,5'-methylenebis(2,4,6-trimethylbenzene-1,3-dicarboxylato)]dibarium(II)] trihydrate], {[Ba2(C23H20O8)(C3H7NO)(H2O)4]·3H2O}n or {[Ba2(BTMIPA)(DMF)(H2O)4]·3H2O}n (1), and poly[[diaqua[µ6-5,5'-methylenebis(2,4,6-trimethylbenzene-1,3-dicarboxylato)]dilead(II)] 2.5-hydrate], {[Pb2(C23H20O8)(H2O)2]·2.5H2O}n or {[Pb2(BTMIPA)(H2O)2]·2.5H2O}n (2), were prepared by the self-assembly of metal salts with the semi-rigid tetracarboxylic acid ligand 5,5'-methylenebis(2,4,6-trimethylisophthalic acid) (H4BTMIPA). Both structures were characterized by elemental analysis (EA), single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), IR spectroscopy and thermogravimetric analysis (TGA). Complex 1 reveals a three-dimensional (3D) flu network formed via bridging tetranuclear secondary building units (SBUs) and complex 2 displays a 3D framework with an sqp topology based on one-dimensional metal chains. The BTMIPA4- ligands adopt a rare coordination mode in 2, although the ligands in both 1 and 2 are X-shaped. The luminescence properties of both complexes were investigated in the solid state.

20.
Sci Adv ; 7(1)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33523836

RESUMO

Liquid droplets have been studied for decades and have recently experienced renewed attention as a simplified model for numerous fascinating physical phenomena occurring on size scales from the cell nucleus to stellar black holes. Here, we present an acoustofluidic centrifugation technique that leverages an entanglement of acoustic wave actuation and the spin of a fluidic droplet to enable nanoparticle enrichment and separation. By combining acoustic streaming and droplet spinning, rapid (<1 min) nanoparticle concentration and size-based separation are achieved with a resolution sufficient to identify and isolate exosome subpopulations. The underlying physical mechanisms have been characterized both numerically and experimentally, and the ability to process biological samples (including DNA segments and exosome subpopulations) has been successfully demonstrated. Together, this acoustofluidic centrifuge overcomes existing limitations in the manipulation of nanoscale (<100 nm) bioparticles and can be valuable for various applications in the fields of biology, chemistry, engineering, material science, and medicine.

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