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1.
Cell ; 174(5): 1188-1199.e14, 2018 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-30057118

RESUMEN

In stationary-phase Escherichia coli, Dps (DNA-binding protein from starved cells) is the most abundant protein component of the nucleoid. Dps compacts DNA into a dense complex and protects it from damage. Dps has also been proposed to act as a global regulator of transcription. Here, we directly examine the impact of Dps-induced compaction of DNA on the activity of RNA polymerase (RNAP). Strikingly, deleting the dps gene decompacted the nucleoid but did not significantly alter the transcriptome and only mildly altered the proteome during stationary phase. Complementary in vitro assays demonstrated that Dps blocks restriction endonucleases but not RNAP from binding DNA. Single-molecule assays demonstrated that Dps dynamically condenses DNA around elongating RNAP without impeding its progress. We conclude that Dps forms a dynamic structure that excludes some DNA-binding proteins yet allows RNAP free access to the buried genes, a behavior characteristic of phase-separated organelles.


Asunto(s)
ADN Bacteriano , Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica , Transcripción Genética , Proteínas de la Membrana Bacteriana Externa/metabolismo , Enzimas de Restricción del ADN/metabolismo , Proteínas de Unión al ADN/metabolismo , ARN Polimerasas Dirigidas por ADN/metabolismo , Holoenzimas/metabolismo , Microscopía Fluorescente , Poliestirenos/química , Proteoma , Análisis de Secuencia de ARN , Estrés Mecánico , Transcriptoma
2.
Proc Natl Acad Sci U S A ; 121(28): e2403143121, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38959041

RESUMEN

Currently, the nanofluidic synapse can only perform basic neuromorphic pulse patterns. One immediate problem that needs to be addressed to further its capability of brain-like computing is the realization of a nanofluidic spiking device. Here, we report the use of a poly(3,4-ethylenedioxythiophene) polystyrene sulfonate membrane to achieve bionic ionic current-induced spiking. In addition to the simulation of various electrical pulse patterns, our synapse could produce transmembrane ionic current-induced spiking, which is highly analogous to biological action potentials with similar phases and excitability. Moreover, the spiking properties could be modulated by ions and neurochemicals. We expect that this work could contribute to biomimetic spiking computing in solution.


Asunto(s)
Potenciales de Acción , Poliestirenos , Sinapsis , Potenciales de Acción/fisiología , Sinapsis/fisiología , Poliestirenos/química , Nanotecnología/métodos , Nanotecnología/instrumentación
3.
Proc Natl Acad Sci U S A ; 120(4): e2213441120, 2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36649431

RESUMEN

A twin boundary (TB) is a common low energy planar defect in crystals including those with the atomic diamond structure (C, Si, Ge, etc.). We study twins in a self-assembled soft matter block copolymer (BCP) supramolecular crystal having the double diamond (DD) structure, consisting of two translationally shifted, interpenetrating diamond networks of the minority polydimethyl siloxane block embedded in a polystyrene block matrix. The coherent, low energy, mirror-symmetric double tubular network twin has one minority block network with its nodes offset from the (222) TB plane, while nodes of the second network lie in the plane of the boundary. The offset network, although at a scale about a factor of 103 larger, has precisely the same geometry and symmetry as a (111) twin in atomic single diamond where the tetrahedral units spanning the TB retain nearly the same strut (bond) lengths and strut (bond) angles as in the normal unit cell. In DD, the second network undergoes a dramatic restructuring-the tetrahedral nodes transform into two new types of mirror-symmetric nodes (pentahedral and trihedral) which alternate and link to form a hexagonal mesh in the plane of the TB. The collective reorganization of the supramolecular packing highlights the hierarchical structure of ordered BCP phases and emphasizes the remarkable malleability of soft matter.


Asunto(s)
Vendajes , Diamante , Grupos Minoritarios , Polímeros , Poliestirenos
4.
Proc Natl Acad Sci U S A ; 120(37): e2305995120, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37669392

RESUMEN

To minimize the incorrect use of antibiotics, there is a great need for rapid and inexpensive tests to identify the pathogens that cause an infection. The gold standard of pathogen identification is based on the recognition of DNA sequences that are unique for a given pathogen. Here, we propose and test a strategy to develop simple, fast, and highly sensitive biosensors that make use of multivalency. Our approach uses DNA-functionalized polystyrene colloids that distinguish pathogens on the basis of the frequency of selected short DNA sequences in their genome. Importantly, our method uses entire genomes and does not require nucleic acid amplification. Polystyrene colloids grafted with specially designed surface DNA probes can bind cooperatively to frequently repeated sequences along the entire genome of the target bacteria, resulting in the formation of large and easily detectable colloidal aggregates. Our detection strategy allows "mix and read" detection of the target analyte; it is robust and highly sensitive over a wide concentration range covering, in the case of our test target genome Escherichia coli bl21-de3, 10 orders of magnitude from [Formula: see text] to [Formula: see text] copies/mL. The sensitivity compares well with state-of-the-art sensing techniques and has excellent specificity against nontarget bacteria. When applied to real samples, the proposed technique shows an excellent recovery rate. Our detection strategy opens the way to developing a robust platform for pathogen detection in the fields of food safety, disease control, and environmental monitoring.


Asunto(s)
ADN , Poliestirenos , Antibacterianos , Coloides , Monitoreo del Ambiente , Escherichia coli
5.
J Biol Chem ; 300(4): 107154, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38479603

RESUMEN

Styrene-maleic acid (SMA) and similar amphiphilic copolymers are known to cut biological membranes into lipid nanoparticles/nanodiscs containing membrane proteins apparently in their relatively native membrane lipid environment. Our previous work demonstrated that membrane raft microdomains resist such disintegration by SMA. The use of SMA in studying membrane proteins is limited by its heterogeneity and the inability to prepare defined derivatives. In the present paper, we demonstrate that some amphiphilic peptides structurally mimicking SMA also similarly disintegrate cell membranes. In contrast to the previously used copolymers, the simple peptides are structurally homogeneous. We found that their membrane-disintegrating activity increases with their length (reaching optimum at 24 amino acids) and requires a basic primary structure, that is, (XXD)n, where X represents a hydrophobic amino acid (optimally phenylalanine), D aspartic acid, and n is the number of repeats of these triplets. These peptides may provide opportunities for various well-defined potentially useful modifications in the study of membrane protein biochemistry. Our present results confirm a specific character of membrane raft microdomains.


Asunto(s)
Proteínas de la Membrana , Péptidos , Animales , Humanos , Membrana Celular/metabolismo , Membrana Celular/química , Maleatos/química , Microdominios de Membrana/metabolismo , Microdominios de Membrana/química , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Péptidos/química , Poliestirenos/química , Línea Celular
6.
Proc Natl Acad Sci U S A ; 119(34): e2203346119, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35969757

RESUMEN

Plastic waste represents one of the most urgent environmental challenges facing humankind. Upcycling has been proposed to solve the low profitability and high market sensitivity of known recycling methods. Existing upcycling methods operate under energy-intense conditions and use precious-metal catalysts, but produce low-value oligomers, monomers, and common aromatics. Herein, we report a tandem degradation-upcycling strategy to exploit high-value chemicals from polystyrene (PS) waste with high selectivity. We first degrade PS waste to aromatics using ultraviolet (UV) light and then valorize the intermediate to diphenylmethane. Low-cost AlCl3 catalyzes both the reactions of degradation and upcycling at ambient temperatures under atmospheric pressure. The degraded intermediates can advantageously serve as solvents for processing the solid plastic wastes, forming a self-sustainable circuitry. The low-value-input and high-value-output approach is thus substantially more sustainable and economically viable than conventional thermal processes, which operate at high-temperature, high-pressure conditions and use precious-metal catalysts, but produce low-value oligomers, monomers, and common aromatics. The cascade strategy is resilient to impurities from plastic waste streams and is generalizable to other high-value chemicals (e.g., benzophenone, 1,2-diphenylethane, and 4-phenyl-4-oxo butyric acid). The upcycling to diphenylmethane was tested at 1-kg laboratory scale and attested by industrial-scale techno-economic analysis, demonstrating sustainability and economic viability without government subsidies or tax credits.


Asunto(s)
Poliestirenos , Reciclaje , Eliminación de Residuos , Plásticos/síntesis química , Poliestirenos/química , Eliminación de Residuos/métodos , Solventes
7.
Chem Soc Rev ; 53(21): 10575-10603, 2024 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-39254255

RESUMEN

The rapid development of wearable and implantable electronics has enabled the real-time transmission of electrophysiological signals in situ, thus allowing the precise monitoring and regulation of biological functions. Devices based on organic materials tend to have low moduli and intrinsic stretchability, making them ideal choices for the construction of seamless bioelectronic interfaces. In this case, as an organic ionic-electronic conductor, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) has low impedance to offer a high signal-to-noise ratio for monitoring bioelectrical signals, which has become one of the most promising conductive polymers. However, the initial conductivity and stretchability of pristine PEDOT:PSS are insufficient to meet the application requirements, and there is a trade-off between their improvement. In addition, PEDOT:PSS has poor stability in aqueous environments due to the hygroscopicity of the PSS chains, which severely limits its long-term applications in water-rich bioelectronic interfaces. Considering the growing demands of multi-function integration, the high-resolution fabrication of electronic devices is urgent. It is a great challenge to maintain both electrical and mechanical performance after miniaturization, particularly at feature sizes below 100 µm. In this review, we focus on the combined improvement in the conductivity and stretchability of PEDOT:PSS, as well as the corresponding mechanisms in detail. Also, we summarize the effective strategies to improve the stability of PEDOT:PSS in aqueous environments, which plays a vital role in long-term applications. Finally, we introduce the reliable micropatterning technologies and PEDOT:PSS-based stretchable optoelectronic devices applied at bio-interfaces.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes , Polímeros , Dispositivos Electrónicos Vestibles , Polímeros/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Poliestirenos/química , Electrónica , Humanos , Conductividad Eléctrica , Tiofenos
8.
Nano Lett ; 24(21): 6218-6224, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38757765

RESUMEN

Nanopore sensing is a popular biosensing strategy that is being explored for the quantitative analysis of biomarkers. With low concentrations of analytes, nanopore sensors face challenges related to slow response times and selectivity. Here, we demonstrate an approach to rapidly detect species at ultralow concentrations using an optical nanopore blockade sensor for quantitative detection of the protein vascular endothelial growth factor (VEGF). This sensor relies on monitoring fluorescent polystyrene nanoparticles blocking nanopores in a nanopore array of 676 nanopores. The fluorescent signal is read out using a wide-field fluorescence microscope. Nonspecific blockade events are then distinguished from specific blockade events based on the ability to pull the particles out of the pore using an applied electric field. This allows the detection of VEGF at sub-picomolar concentration in less than 15 min.


Asunto(s)
Técnicas Biosensibles , Nanoporos , Poliestirenos , Factor A de Crecimiento Endotelial Vascular , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Factor A de Crecimiento Endotelial Vascular/análisis , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Poliestirenos/química , Nanopartículas/química , Humanos , Microscopía Fluorescente/métodos
9.
J Am Chem Soc ; 146(21): 14391-14396, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38748513

RESUMEN

Model membranes interfaced with bioelectronics allow for the exploration of fundamental cell processes and the design of biomimetic sensors. Organic conducting polymers are an attractive surface on which to study the electrical properties of membranes because of their low impedance, high biocompatibility, and hygroscopic nature. However, establishing supported lipid bilayers (SLBs) on conducting polymers has lagged significantly behind other substrate materials, namely, for challenges in membrane electrical sealing and stability. Unlike SLBs that are highly dependent on surface interactions, droplet interface bilayers (DIBs) and droplet hydrogel bilayers (DHBs) leverage the energetically favorable organization of phospholipids at atomically smooth liquid interfaces to build high-integrity membranes. For the first time, we report the formation of droplet polymer bilayers (DPBs) between a lipid-coated aqueous droplet and the high-performing conducting polymer poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT:PSS). The resulting bilayers can be produced from a range of lipid compositions and demonstrate strong electrical sealing that outcompetes SLBs. DPBs are subsequently translated to patterned and planar microelectrode arrays to ease barriers to implementation and improve the reliability of membrane formation. This platform enables more reproducible and robust membranes on conducting polymers to further the mission of merging bioelectronics and synthetic, natural, or hybrid bilayer membranes.


Asunto(s)
Membrana Dobles de Lípidos , Membrana Dobles de Lípidos/química , Polímeros/química , Poliestirenos/química , Propiedades de Superficie
10.
Anal Chem ; 96(35): 14274-14282, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39159408

RESUMEN

The comprehensive understanding of the orientation of antibodies on a solid surface is crucial for affinity-based sensing mechanisms. In this study, we demonstrated that the orientation of primary antibodies modified on carboxy-functionalized polystyrene (PS) particles can be analyzed using zeta potential behavior at different pH based on the combined Gouy-Chapman-Stern model and the acid dissociation of carboxy groups and antibodies. We observed that at low surface concentrations of the primary antibody, a side-on orientation was predominant. However, at higher concentrations (approximately 30000 antibodies per PS particle), the orientation shifted to an end-on type due to steric hindrance. Furthermore, the reaction mechanism of the secondary antibody exhibited pH-dependent behavior. At pH > 7, the zeta potential changes were attributed to the antibody-antibody reaction, whereas at pH < 7, adsorption of secondary antibody onto the PS particle was observed, leading to a change in the orientation of the primary antibody modified on the PS particle to an end-on type. The change in zeta potential due to secondary antibody binding indicated a detection limit of 37000 antibodies per PS particle. As a result, we revealed that the analysis of zeta potential behavior enables the evaluation of antibody orientation and the detection of zeptomole order antibodies. This study represents the first demonstration of this capability. We anticipate that the present concept and results will broaden the quantitative application of zeta potential measurements and have significant implications for research areas, including physical chemistry and analytical chemistry.


Asunto(s)
Anticuerpos , Poliestirenos , Poliestirenos/química , Concentración de Iones de Hidrógeno , Anticuerpos/química , Anticuerpos/inmunología , Propiedades de Superficie , Tamaño de la Partícula
11.
Anal Chem ; 96(4): 1597-1605, 2024 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-38235613

RESUMEN

Nanobodies, which represent the next generation of antibodies due to their unique properties, face a significant limitation in their poor physical adsorption on solid supports. In this study, we successfully discovered polystyrene binding nanobodies from a synthetic nanobody library. Notably, bivalent nanobody B2 exhibited high affinity for polystyrene (0.7 nM for ELISA saturation binding analysis and 15.6 nM for isothermal titration calorimetry), displaying a pH-dependent behavior. Remarkably, hydrophobic and electrostatic interactions contribute minimally to the binding process. Molecular modeling provided insights into the interaction between B2 and polystyrene, revealing that the Trp51 residue within the CDR2 loop formed an aromatic H-bond with polystyrene at a distance of 2.74 Å, thus explaining the observed reduction in B2 affinity caused by Trp51 mutations. To explore B2's potential in protein immobilization, we constructed a bispecific nanobody by fusing B2 to an anticarcinoembryonic antigen nanobody 11C12, which cannot be immobilized on polystyrene through passive adsorption. Remarkably, the fusion construct achieved effective immobilization on polystyrene within 5 min by passing the need for periplasmic protein purification despite its low expression level. Moreover, the fusion construct demonstrated excellent linearity in the chemiluminescent enzyme immunoassay. For the first time, this study reports a simplified and seamless platform for the oriented immobilization of nanobody. Importantly, the entire process eliminated the need for protein purification, enabling efficient and rapid immobilization of fusion proteins directly from crude cell extracts, even when the expression level was low. Our developed process dramatically reduced the processing time from 2.5 days to just 5 min.


Asunto(s)
Anticuerpos de Dominio Único , Poliestirenos , Inmunoensayo , Ensayo de Inmunoadsorción Enzimática , Anticuerpos
12.
Anal Chem ; 96(12): 4978-4986, 2024 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-38471057

RESUMEN

Bioaccumulation of nanoplastic particles has drawn increasing attention regarding environmental sustainability and biosafety. How nanoplastic particles interact with the cellular milieu still remains elusive. Herein, we exemplify a general approach to profile the composition of a "protein corona" interacting with nanoparticles via the photocatalytic protein proximity labeling method. To enable photocatalytic proximity labeling of the proteome interacting with particles, iodine-substituted BODIPY (I-BODIPY) is selected as the photosensitizer and covalently conjugated onto amino-polystyrene nanoparticles as a model system. Next, selective proximity labeling of interacting proteins is demonstrated using I-BODIPY-labeled nanoplastic particles in both Escherichia coli lysate and live alpha mouse liver 12 cells. Mechanistic studies reveal that the covalent modifications of proteins by an aminoalkyne substrate are conducted via a reactive oxygen species photosensitization pathway. Further proteomic analysis uncovers that mitochondria-related proteins are intensively involved in the protein corona, indicating substantial interactions between nanoplastic particles and mitochondria. In addition, proteostasis network components are also identified, accompanied by consequent cellular proteome aggregation confirmed by fluorescence imaging. Together, this work exemplifies a general strategy to interrogate the composition of the protein corona of nanomaterials by endowing them with photooxidation properties to enable photocatalytic protein proximity labeling function.


Asunto(s)
Compuestos de Boro , Nanopartículas , Corona de Proteínas , Animales , Ratones , Microplásticos , Proteoma , Proteómica , Poliestirenos
13.
Anal Chem ; 96(18): 7179-7186, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38661266

RESUMEN

This study uses real-time monitoring, at microsecond time scales, with a charge-sensing particle detector to investigate the evaporation and fission processes of methanol/micrometer-sized polystyrene beads (PS beads) droplets and bacterial particles droplets generated via electrospray ionization (ESI) under elevated temperatures. By incrementally raising capillary temperatures, the solvent, such as methanol on 0.75 µm PS beads, experiences partial evaporation. Further temperature increase induces fission, and methanol molecules continue to evaporate until PS ions are detected after this range. Similar partial evaporation is observed on 3 µm PS beads. However, the shorter period of the fission temperature range is necessary compared to 0.75 µm PS beads. For the spherical-shaped bacterium, Staphylococcus aureus, the desolvation process shows a similar fission period as compared to 0.75 µm PS beads. Comparably, the rod-shaped bacteria, Escherichia coli EC11303, and E. coli strain W have shorter fission periods than S. aureus. This research provides insights into the evaporation and fission mechanisms of ESI droplets containing different sizes and shapes of micrometer-sized particles, contributing to a better understanding of gaseous macroion formation.


Asunto(s)
Escherichia coli , Poliestirenos , Espectrometría de Masa por Ionización de Electrospray , Staphylococcus aureus , Poliestirenos/química , Escherichia coli/química , Tamaño de la Partícula , Temperatura , Volatilización , Metanol/química , Microesferas
14.
Anal Chem ; 96(17): 6511-6516, 2024 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-38634936

RESUMEN

Charge detection quadrupole ion trap mass spectrometry (CD-QIT MS) is an effective way of achieving the mass analysis of microparticles with ultrahigh mass. However, its mass accuracy and resolution are still poor. To enhance the performance of CD-QIT MS, the resolution Rpeak of each peak in the mass spectra resulting from an individual particle was assessed, and a peak filtering algorithm that can filter out particle adducts and clusters with a lower Rpeak was proposed. By using this strategy, more accurate mass information about the analyzed particles could be obtained, and the mass resolution of CD-QIT MS was improved by nearly 2-fold, which was demonstrated by using the polystyrene (PS) particle size standards and red blood cells (RBCs). Benefiting from these advantages of the peak filtering algorithm, the baseline separation and relative quantification of 3 and 4 µm PS particles were achieved. To prove the application value of this algorithm in a biological system, the mass of yeast cells harvested at different times was measured, and it was found that the mixed unbudded and budded yeast cells, which otherwise would not be differentiable, were distinguished and quantified with the algorithm.


Asunto(s)
Algoritmos , Espectrometría de Masas , Tamaño de la Partícula , Poliestirenos , Poliestirenos/química , Espectrometría de Masas/métodos , Eritrocitos/citología , Eritrocitos/química , Saccharomyces cerevisiae , Humanos
15.
Anal Chem ; 96(42): 16842-16853, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39388602

RESUMEN

Limitations in the sensitivity, linear detection range, and cross-reaction of lateral flow immunoassays mainly hamper their application in rapid screening for multiple targets. In this work, we designed a new time-resolved fluorescence immunoassay (TRFIA) platform to overcome these limitations. This platform uses europium chelate polystyrene (PS@Eu) nanoparticles conjugated with monoclonal antibodies to sense multiple mycotoxins. We employed a competitive TRFIA protocol in which the conjugated PS@Eu was used on the surfaces of photonic microbead arrays (PMAs). The TRFIA signal of PMAs on the pad was recorded with the digital time-resolved fluorescence reader. The developed TRFIA shows wide detection linear ranges (0.01-1000 ng/mL for DON, 0.1-100 ng/mL for OTA, and 0.01-100 ng/mL for AFB1), low limits of detection (LODs) (7.9 pg/mL for DON, 18 pg/mL for OTA, and 7.7 pg/mL for AFB1), good specificity, good recovery ratios (76.68-117.26%), and good reproducibility in grain samples. The simulated fluorescence enhancement effect of PMA indicated that the electric field distribution on the surface of PS@Eu on PMA is twice higher than that on the surface of PS@Eu. The new TRFIA for three kinds of mycotoxins was 1000-fold more sensitive than the classical TRFIA, and it has great potential application in rapid screening for multiple targets.


Asunto(s)
Micotoxinas , Fotones , Poliestirenos , Micotoxinas/análisis , Poliestirenos/química , Europio/química , Límite de Detección , Inmunoensayo/métodos , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/química , Fluorescencia , Factores de Tiempo , Tricotecenos/análisis , Ocratoxinas/análisis , Aflatoxina B1/análisis , Aflatoxina B1/inmunología , Nanopartículas/química
16.
Anal Chem ; 96(26): 10662-10668, 2024 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-38875183

RESUMEN

The uptake of plastic particles by plants and their transport through the food chain make great risks to biota and human health. Therefore, it is important to trace plastic particles in the plant. Traditional fluorescence imaging in plants usually suffers significant autofluorescence background. Here, we report a persistent luminescence nanoplatform for autofluorescence-free imaging and quantitation of submicrometer plastic particles in plant. The nanoplatform was fabricated by doping persistent luminescence nanoparticles (PLNPs) onto polystyrene (PS) nanoparticles. Cr3+-doped zinc gallate PLNP was employed as the dopant for autofluorescence-free imaging due to its persistent luminescence nature. In addition, the Ga element in PLNP was used as a proxy to quantify the PS in the plant by inductively coupled plasma mass spectrometry (ICP-MS). Thus, the developed nanoplatform allows not only dual-mode autofluorescence-free imaging (persistent luminescence and laser-ablation ICP-MS) but also ICP-MS quantitation for tracking PS in plant. Application of this nanoplatform in a typical plant model Arabidopsis thaliana revealed that PS mainly distributed in the root (>99.45%) and translocated very limited (<0.55%) to the shoot. The developed nanoplatform has great potential for quantitative tracing of submicrometer plastic particles to investigate the environmental process and impact of plastic particles.


Asunto(s)
Arabidopsis , Nanopartículas , Arabidopsis/química , Nanopartículas/química , Luminiscencia , Plásticos/química , Tamaño de la Partícula , Poliestirenos/química , Imagen Óptica
17.
Anal Chem ; 96(17): 6847-6852, 2024 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-38639290

RESUMEN

Organic photoelectrochemical transistor (OPECT) has shown substantial potential in the development of next-generation bioanalysis yet is limited by the either-or situation between the photoelectrode types and the channel types. Inspired by the dual-photoelectrode systems, we propose a new architecture of dual-engine OPECT for enhanced signal modulation and its biosensing application. Exemplified by incorporating the CdS/Bi2S3 photoanode and Cu2O photocathode within the gate-source circuit of Ag/AgCl-gated poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) channel, the device shows enhanced modulation capability and larger transconductance (gm) against the single-photoelectrode ones. Moreover, the light irritation upon the device effectively shifts the peak value of gm to zero gate voltage without degradation and generates larger current steps that are advantageous for the sensitive bioanalysis. Based on the as-developed dual-photoelectrode OPECT, target-mediated recycling and etching reactions are designed upon the CdS/Bi2S3, which could result in dual signal amplification and realize the sensitive microRNA-155 biodetection with a linear range from 1 fM to 100 pM and a lower detection limit of 0.12 fM.


Asunto(s)
Cobre , Técnicas Electroquímicas , Sulfuros , Tiofenos , Técnicas Electroquímicas/instrumentación , Cobre/química , Sulfuros/química , Compuestos de Cadmio/química , Técnicas Biosensibles/instrumentación , Bismuto/química , Transistores Electrónicos , Procesos Fotoquímicos , Poliestirenos/química , MicroARNs/análisis , Electrodos , Polímeros/química
18.
Anal Chem ; 96(18): 7014-7021, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38659215

RESUMEN

Membrane-based lateral flow immunoassays (LFAs) have been employed as early point-of-care (POC) testing tools in clinical settings. However, the varying membrane properties, uncontrollable sample transport in LFAs, visual readout, and required large sample volumes have been major limiting factors in realizing needed sensitivity and desirable precise quantification. Addressing these challenges, we designed a membrane-free system in which the desirable three-dimensional (3D) structure of the detection zone is imitated and used a small pump for fluid flow and fluorescence as readout, all the while maintaining a one-step assay protocol. A hydrogel-like protein-polyelectrolyte complex (PPC) within a polyelectrolyte multilayer (PEM) was developed as the test line by complexing polystreptavidin (pSA) with poly(diallyldimethylammonium chloride) (PDDA), which in turn was layered with poly(acrylic acid) (PAA) resulting in a superior 3D streptavidin-rich test line. Since the remainder of the microchannel remains material-free, good flow control is achieved, and with the total volume of 20 µL, 7.5-fold smaller sample volumes can be used in comparison to conventional LFAs. High sensitivity with desirable reproducibility and a 20 min total assay time were achieved for the detection of NT-proBNP in plasma with a dynamic range of 60-9000 pg·mL-1 and a limit of detection of 56 pg·mL-1 using probe antibody-modified fluorescence nanoparticles. While instrument-free visual detection is no longer possible, the developed lateral flow channel platform has the potential to dramatically expand the LFA applicability, as it overcomes the limitations of membrane-based immunoassays, ultimately improving the accuracy and reducing the sample volume so that finger-prick analyses can easily be done in a one-step assay for analytes present at very low concentrations.


Asunto(s)
Biomarcadores , Compuestos de Amonio Cuaternario , Humanos , Inmunoensayo/métodos , Biomarcadores/análisis , Biomarcadores/sangre , Péptido Natriurético Encefálico/sangre , Péptido Natriurético Encefálico/análisis , Límite de Detección , Resinas Acrílicas/química , Fragmentos de Péptidos/análisis , Fragmentos de Péptidos/sangre , Polietilenos/química , Poliestirenos/química
19.
Biochem Biophys Res Commun ; 734: 150719, 2024 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-39362032

RESUMEN

Plastics are an essential part of human life and their production is increasing every year. Plastics degrade into small particles (<5 mm, microplastics, MPs) in the environment due to various factors. MPs are widely distributed in the environment, and all living organisms are exposed to the effects of MPs. Extracellular vesicles (EVs) are small membrane particles surrounded by a lipid bilayer that are released into the environment by various cell types and are highly involved in inter- and intra-cellular communication through the exchange of proteins, nucleic acids, and lipids between cells. There have been numerous reports of adverse effects associated with the accumulation of MPs in human and animal cells, with recent studies showing that plastic treatment increases the number of EVs released from cells, but the mechanisms by which MPs accumulate and move between cells remain unclear. In this study, we investigated whether polystyrene (PS)-MPs are transferred cell-to-cell via EVs. This study showed that cell-derived EVs can transport plastic particles. Furthermore, we confirmed the accumulation of PS-MPs transported by EVs within cells using a real-time imaging device. This study provides an understanding of potential EVs-mediated effects of PS-MPs on organisms and suggests directions for further research.


Asunto(s)
Comunicación Celular , Vesículas Extracelulares , Microplásticos , Poliestirenos , Poliestirenos/metabolismo , Poliestirenos/química , Microplásticos/toxicidad , Microplásticos/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Animales , Transporte Biológico , Línea Celular
20.
Biochem Biophys Res Commun ; 734: 150619, 2024 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-39232458

RESUMEN

Since the emergence of a global outbreak of mpox in 2022, understanding the transmission pathways and mechanisms of Orthopoxviruses, including vaccinia virus (VACV), has become paramount. Nanoplastic pollution has become a significant global issue due to its widespread presence in the environment and potential adverse effects on human health. These emerging pollutants pose substantial risks to both living organisms and the environment, raising serious health concerns related to their proliferation. Despite this, the effects of nanoparticles on viral transmission dynamics remain unclear. This study explores how polystyrene nanoparticles (PS-NPs) influence the transmission of VACV through migrasomes. We demonstrate that PS-NPs accelerate the formation of migrasomes early in the infection process, facilitating VACV entry as soon as 15 h post-infection (hpi), compared to the usual onset at 36 hpi. Immunofluorescence and transmission electron microscopy (TEM) reveal significant co-localization of VACV with migrasomes induced by PS-NPs by 15 hpi. This interaction coincides with an increase in lipid droplet size, attributed to higher cholesterol levels influenced by PS-NPs. By 36 hpi, migrasomes exposed to both PS-NPs and VACV exhibit distinct features, such as retraction fibers and larger lipid droplets, emphasizing their critical role in cargo transport during viral infections. These results suggest that PS-NPs may act as modulators of viral transmission dynamics through migrasomes, with potential implications for antiviral strategies and environmental health.


Asunto(s)
Nanopartículas , Poliestirenos , Virus Vaccinia , Poliestirenos/química , Nanopartículas/química , Virus Vaccinia/efectos de los fármacos , Virus Vaccinia/fisiología , Virus Vaccinia/metabolismo , Humanos , Microplásticos/toxicidad , Internalización del Virus/efectos de los fármacos , Animales , Línea Celular , Vaccinia/virología , Vaccinia/metabolismo , Vaccinia/transmisión
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