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1.
Anal Chem ; 96(17): 6847-6852, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38639290

RESUMO

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.


Assuntos
Cobre , Técnicas Eletroquímicas , Sulfetos , Tiofenos , Técnicas Eletroquímicas/instrumentação , Cobre/química , Sulfetos/química , Compostos de Cádmio/química , Técnicas Biossensoriais/instrumentação , Bismuto/química , Transistores Eletrônicos , Processos Fotoquímicos , Poliestirenos/química , MicroRNAs/análise , Eletrodos , Polímeros/química
2.
Small ; 20(15): e2306365, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009777

RESUMO

Oxygen vacancy defects (OVs) are one of the main strategies for nanomaterials modification to improve the photoactivity, but current methods for fabricating OVs are usually complicated and harsh. It is important to develop simple, rapid, safe, and mild methods to fabricate OVs. By studying the effects of different weak reducing agents, the concentration of the reducing agent and the reaction time on fabrication of OVs, it is found that L-ascorbic acid (AA) gently and rapidly induces the increase of OVs in Bi4O5Br2 at room temperature. The increased OVs not only improve the adsorption of visible light, but also enhance the photocurrent response. Based on this, the preparation of OVs in Bi4O5Br2 is employed to the development of a photoelectrochemical biosensor for the detection of DNA demethylase of methyl-CpG binding domain protein 2 (MBD2). The biosensor shows a wide linear range of 0.1-400 ng mL-1 and a detection limit as low as 0.03 ng mL-1 (3σ). In addition, the effect of plasticizers on MBD2 activity is evaluated using this sensor. This work not only provides a novel method to prepare OVs in bismuth rich materials, but also explores a new novel evaluation tool for studying the ecotoxicological effects of contaminants.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Ácido Ascórbico , Oxigênio , DNA , Luz , Técnicas Biossensoriais/métodos
3.
Nano Lett ; 23(22): 10157-10163, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37909774

RESUMO

A levitated nonspherical nanoparticle in a vacuum is ideal for studying quantum rotations and is an ultrasensitive torque detector for probing fundamental particle-surface interactions. Here, we optically levitate a silica nanodumbbell in a vacuum at 430 nm away from a sapphire surface and drive it to rotate at GHz frequencies. The relative linear speed between the tip of the nanodumbbell and the surface reaches 1.4 km s-1 at a submicrometer separation. The rotating nanodumbbell near the surface demonstrates a torque sensitivity of (5.0 ± 1.1) × 10-26 N m Hz-1/2 at room temperature. Moreover, we probed the near-field laser intensity distribution beyond the optical diffraction limit with a nanodumbbell levitated near a nanograting. Our numerical simulations show that the system can measure the Casimir torque and will improve the detection limit of non-Newtonian gravity by several orders of magnitude.

4.
Dentomaxillofac Radiol ; 53(5): 271-280, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38814810

RESUMO

Cystic lesions of the gnathic bones present challenges in differential diagnosis. In recent years, artificial intelligence (AI) represented by deep learning (DL) has rapidly developed and emerged in the field of dental and maxillofacial radiology (DMFR). Dental radiography provides a rich resource for the study of diagnostic analysis methods for cystic lesions of the jaws and has attracted many researchers. The aim of the current study was to investigate the diagnostic performance of DL for cystic lesions of the jaws. Online searches were done on Google Scholar, PubMed, and IEEE Xplore databases, up to September 2023, with subsequent manual screening for confirmation. The initial search yielded 1862 titles, and 44 studies were ultimately included. All studies used DL methods or tools for the identification of a variable number of maxillofacial cysts. The performance of algorithms with different models varies. Although most of the reviewed studies demonstrated that DL methods have better discriminative performance than clinicians, further development is still needed before routine clinical implementation due to several challenges and limitations such as lack of model interpretability, multicentre data validation, etc. Considering the current limitations and challenges, future studies for the differential diagnosis of cystic lesions of the jaws should follow actual clinical diagnostic scenarios to coordinate study design and enhance the impact of AI in the diagnosis of oral and maxillofacial diseases.


Assuntos
Aprendizado Profundo , Cistos Maxilomandibulares , Humanos , Cistos Maxilomandibulares/diagnóstico por imagem , Diagnóstico Diferencial , Doenças Maxilomandibulares/diagnóstico por imagem
5.
Anal Chem ; 95(2): 1454-1460, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36538530

RESUMO

Organic photoelectrochemical transistor (OPECT) bioanalytics has recently appeared as a promising route for biological measurements, which has major implications in both next-generation photoelectrochemical (PEC) bioanalysis and futuristic biorelated implementations. Via biological dissociation of materials, bioetching is a useful technique for bio-manufacturing and bioanalysis. The intersection of these two domains is expected to be a possible way to achieve innovative OPECT bioanalytics. Herein, we validate such a possibility, which is exemplified by alkaline phosphatase (ALP)-mediated bioetching of a CoOOH/BiVO4 gate for a signal-on OPECT immunoassay of human immunoglobulin G (HIgG) as the model target. Specifically, target-dependent bioetching of the upper CoOOH layer could result into an enhanced electrolyte contact and light accessibility to BiVO4, leading to the modulated response of the polymeric poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) channel that could be monitored by the channel current. The introduced biosensor achieves sensitive detection of HIgG with high selectivity and sensitivity. This work features bioetching-enabled high-efficacy OPECT bioanalysis and is anticipated to serve as a generic protocol, considering the diverse bioetching routes.


Assuntos
Fosfatase Alcalina , Técnicas Biossensoriais , Humanos , Fosfatase Alcalina/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos , Óxidos
6.
Nat Mater ; 21(9): 1024-1028, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35970964

RESUMO

Electron spins in van der Waals materials are playing a crucial role in recent advances in condensed-matter physics and spintronics. However, nuclear spins in van der Waals materials remain an unexplored quantum resource. Here we report optical polarization and coherent control of nuclear spins in a van der Waals material at room temperature. We use negatively charged boron vacancy ([Formula: see text]) spin defects in hexagonal boron nitride to polarize nearby nitrogen nuclear spins. We observe the Rabi frequency of nuclear spins at the excited-state level anti-crossing of [Formula: see text] defects to be 350 times larger than that of an isolated nucleus, and demonstrate fast coherent control of nuclear spins. Further, we detect strong electron-mediated nuclear-nuclear spin coupling that is five orders of magnitude larger than the direct nuclear-spin dipolar coupling, enabling multi-qubit operations. Our work opens new avenues for the manipulation of nuclear spins in van der Waals materials for quantum information science and technology.

7.
BMC Surg ; 23(1): 149, 2023 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-37270470

RESUMO

BACKGROUND: We aimed to compare the difference between the therapeutic effects of percutaneous vertebroplasty (PVP) as well as PVP combined with erector spinae plane blocked (ESPB) in osteoporotic vertebral compression fractures (OVCFs) therapy. METHODS: After the reception, 100 affected people to OVCFs were randomly divided into the PVP group as a control as well as the PVP + ESPB group as the observation, which included fifty affected people per group. The visual analog scale (VAS) for pain as well as the Oswestry Disability Index (ODI) per group was assessed before the operation, two hours after the operation, and when patients were discharged from the hospital. Operating time was also evaluated on the charged bulk of bone cement during the surgery, blood loss during the surgery, as well as operating costs for each group. Additionally, to assess differences, comparisons have been done among available groups in terms of ambulation as well as defecation or stool after the operation at the earlier time. RESULTS: The PVP + ESPB category acquired lower VAS and ODI scores when assessments were processed 2 h after the operation and when they were discharged from a hospital. They also had earlier postoperative ambulation and defecation time than the category of PVP (p < 0.05). Regarding the other indicators, there did not show significant differences. Besides, no complications occurred within both group, either after the operation or when they discharge from the hospital. CONCLUSION: PVP + ESPB for OVCF is related to less VAS, further effective alleviation of pain, and fewer ODI values in affected people after the operation than only PVP. Besides, affected people can involve in ambulation more swiftly. The PVP + ESPB therapy improves the quicker recuperation of intestinal function as well as helps to improve the overall life quality of patients.


Assuntos
Fraturas por Compressão , Bloqueio Nervoso , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Vertebroplastia , Humanos , Fraturas por Compressão/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Resultado do Tratamento , Dor/tratamento farmacológico , Dor/cirurgia , Fraturas por Osteoporose/cirurgia , Cimentos Ósseos , Estudos Retrospectivos
8.
Nano Lett ; 21(18): 7708-7714, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34473524

RESUMO

The recently discovered spin defects in hexagonal boron nitride (hBN), a layered van der Waals material, have great potential in quantum sensing. However, the photoluminescence and the contrast of the optically detected magnetic resonance (ODMR) of hBN spin defects are relatively low so far, which limits their sensitivity. Here we report a record-high ODMR contrast of 46% at room temperature and simultaneous enhancement of the photoluminescence of hBN spin defects by up to 17-fold by the surface plasmon of a gold film microwave waveguide. Our results are obtained with shallow boron vacancy spin defects in hBN nanosheets created by low-energy He+ ion implantation and a gold film microwave waveguide fabricated by photolithography. We also explore the effects of microwave and laser powers on the ODMR and improve the sensitivity of hBN spin defects for magnetic field detection. Our results support the promising potential of hBN spin defects for nanoscale quantum sensing.

9.
Opt Express ; 29(22): 35678-35690, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34808997

RESUMO

Plasmonic nanostructures with dual surface plasmon resonances capable of simultaneously realizing strong light confinement and efficient light radiation are attractive for light-matter interaction and nanoscale optical detection. Here, we propose an optical nanoantenna by adding gold nanoring to the conventional Fano-type resonance antenna. With the help of gold nanoring, the following improvements are simultaneously realized: (1). The near-field intensity of the Fano-type antenna is further enhanced by the Fabry Perot-like resonance formed by the combination of the gold nanoring and the substrate waveguide layer. (2). Directional radiation is realized by the collaboration of the gold nanoring and the Fano-type antenna, thus improving the collection efficiency of the far-field signal. (3). The multi-wavelength tunable performance of the Fano resonance antenna is significantly improved by replacing the superradiation mode in the Fano resonance with the dipole resonance induced by the gold nanoring. The optical properties of the nanoantennas are demonstrated by numerical simulations and practical devices. Therefore, the proposed optical nanoantenna provides a new idea for further improving the performance of conventional Fano-type nanoantennas and opens new horizons for designing plasmonic devices with enhancements in both near- and far-field functionalities, which can be applied in a wide range of applications such as surface-enhanced spectroscopy, photoluminescence, nonlinear nanomaterials/emitters and biomedicine sensing.

10.
Inorg Chem ; 59(23): 17213-17223, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33206511

RESUMO

Mechanochromic luminescence materials have attracted rapidly growing interest. Nevertheless, the designed synthesis of such materials remains a challenge, and there have been few examples based on weak intramolecular interactions. Herein, we report a new approach for preparing mechanochromic luminescence materials of Cu(I) complexes, i.e., constructing a photoluminescence system that bears a large coplanar multinuclear Cu(I) unit showing weak intramolecular π···π interactions with the planar rings of the coordinated ligands in the molecule. Using it, a series of novel mechanochromic luminescent tetranuclear Cu(I) complexes have been successfully designed and synthesized. As revealed by single-crystal X-ray crystallography, these Cu(I) complexes share an identical {Cu4[µ3-η2(N,N),η1(N),η1(N)-pyridyltetrazole]2}2+ planar fragment whose coplanar pyridyl rings exhibit weak intramolecular π···π interactions with the phenyl rings of the coordinated phosphine ligands in the molecule. All of these Cu(I) complexes exhibit reversible mechanochromic luminescence, which can be attributed to the change in the rigidity of the molecular structure resulting from the disruption and restoration of intramolecular π···π interactions between the pyridyl and phenyl rings triggered by grinding and CH2Cl2 vapor, as supported by powder X-ray diffraction and Fourier transform infrared spectrometry. In addition, the results might provide a new route for developing mechanochromic luminescence materials of Cu(I) complexes for intelligent responsive luminescent devices.

11.
Ecotoxicol Environ Saf ; 203: 111000, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32736119

RESUMO

Microplastics are identified as a great threat to marine environments. However, knowledge of their impacts on phytoplankton, especially for the diatoms is scarce. Herein, the effects of different polyvinyl chloride (PVC) microplastic concentrations and contact times (24, 48, 72 and 96 h) on the Fv/Fm and cell density of Phaeodactylum tricornutum (B255), Chaetoceros gracilis (B13) and Thalassiosira sp. (B280) were investigated to evaluate the toxic effects of microplastics on marine diatoms. The effects of PVC microplastics on the morphology of the diatoms was observed by SEM. The order of sensitivity to 1 µm PVC microplastics among three marine diatoms was B13 > B280 > B255, showing that the toxic effects varied with different microalgae species. Furthermore, the presence of a siliceous cell wall played a minimal role in protecting cells from the physical attack of PVC microplastics, with no significant difference from the common cell wall. PVC microplastics caused dose-dependent adverse effects on three marine diatoms. High PVC concentrations (200 mg/L) reduced the chlorophyll content, inhibited Fv/Fm, and affected the photosynthesis of three marine diatoms. The PVC microplastics adsorbed and caused physical damage on the structure of algal cells. Interactions between PVC microplastics and diatoms may be the probable reason for the negative effects of PVC on diatoms.


Assuntos
Diatomáceas/efeitos dos fármacos , Microplásticos/toxicidade , Cloreto de Polivinila/toxicidade , Poluentes Químicos da Água/toxicidade , Adsorção , Clorofila/metabolismo , Diatomáceas/crescimento & desenvolvimento , Diatomáceas/fisiologia , Relação Dose-Resposta a Droga , Microalgas/efeitos dos fármacos , Microalgas/crescimento & desenvolvimento , Microalgas/fisiologia , Fotossíntese/efeitos dos fármacos , Fitoplâncton/efeitos dos fármacos , Fitoplâncton/crescimento & desenvolvimento , Fitoplâncton/fisiologia , Fatores de Tempo
12.
Mikrochim Acta ; 187(8): 424, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32621131

RESUMO

CoMoO4 materials were prepared through a simple hydrothermal method and developed as highly efficient peroxidase mimics for colorimetric determination of H2O2. Based on the different experimental conditions in the synthesis process, the CoMoO4 materials present distinct morphologies, structures, surface properties, and peroxidase mimetic activities. Among them, CoMoO4 nanobelts (NBs) display the best intrinsic peroxidase mimetic abilities due to the high-energy (100) facet exposed, more Co active sites at (100) facet, more negative potential, and larger specific surface area. It can efficiently catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2 to generate a blue oxide. In view of the excellent peroxidase mimetic catalytic activity of CoMoO4 NBs, a rapid, convenient, and ultrasensitive method was successfully established for the visual and colorimetric determination of H2O2. The method exhibits good selectivity, practicability, stability, and reusability, and has a detection limit of 0.27 µM. The peroxidase mimetic catalytic mechanism of CoMoO4 NBs was illustrated according to the kinetic and active species trapping experiments. The method has a good potential for rapid and sensitive determination of H2O2 for biomedical analysis. Graphical abstract Schematic presentation of the process of CoMoO4 nanobelts catalyzing the oxidation of peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2 to generate a typical blue color, which can be applied in rapid and ultrasensitive detection of H2O2 visually.


Assuntos
Colorimetria/métodos , Peróxido de Hidrogênio/análise , Nanoestruturas/química , Benzidinas/química , Catálise , Compostos Cromogênicos/química , Cobalto/química , Peróxido de Hidrogênio/química , Limite de Detecção , Molibdênio/química , Oxirredução , Óxidos/química
13.
Mikrochim Acta ; 187(7): 422, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32617681

RESUMO

Four kinds of Ag3PO4 materials were prepared by controlling the experimental conditions, which were developed as oxidase mimics. Experimental results showed that different synthesis methods led to distinct crystal structures, morphologies, and surface properties, which contributed to diverse oxidase-like activities of Ag3PO4 materials. Among them, Ag3PO4 microcubes (APMCs) can efficiently catalyze the oxidation of colorless 3,3',5,5'-tetramethylbenzidine in the presence of dissolved oxygen to form a blue-colored oxide, presenting the best intrinsic oxidase mimetic ability. The higher-energy [110] facets with more oxygen vacancies exposed and more active sites coupled with more negative charge and larger specific surface area of APMCs contributed to its enhanced oxidase mimetic performance. Besides, mercury ions were proved to remarkably and selectively stimulate the oxidase-like ability of APMCs owing to the formation of Ag-Hg amalgam on its surface. Based on the stimulating effect of Hg2+ towards APMCs, a simple and rapid method for colorimetric determination of Hg2+ was thus established via the significant signal amplification and megascopic color variation. Under the optimal conditions, the sensing system showed a good linear relationship ranging from 0.1 to 7.0 µM and a detection limit of 20 nM for Hg2+, exhibiting high selectivity and good colour stability. Moreover, the colorimetric method was successfully applied to determine Hg2+ in real water samples. Considering these advantages, the developed colorimetric sensing system is expected to hold bright prospects for trace determination of Hg2+ in biological, environmental, and food samples. Graphical abstract The preparation process of Ag3PO4 materials and Hg2+-stimulated enhanced oxidase-like ability of Ag3PO4 microcubes in catalyzing the oxidation of TMB to generate a typical blue color, which can be applied in rapid and ultrasensitive detection of Hg2+ visually.


Assuntos
Colorimetria/métodos , Mercúrio/análise , Fosfatos/química , Compostos de Prata/química , Benzidinas/química , Catálise , Compostos Cromogênicos/química , Água Potável/análise , Limite de Detecção , Oxirredução , Oxigênio/química , Água do Mar/análise , Poluentes Químicos da Água/análise
14.
Mikrochim Acta ; 186(2): 118, 2019 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-30661119

RESUMO

Nanocrystals (NCs) of type Cu2ZnSn(SxSe1-x)4 (CZTSSe) were prepared via a solvothermal approach. They are shown to be highly efficient peroxidase (POx) mimics for colorimetric detection of H2O2. By varying the molar ratio of S and Se during preparation, the NCs showed different crystal structures, morphologies, surface properties, and POx-like activities. Among them, the type CZTSSe-0.25 NCs exhibit the strongest POx-like activities towards the catalytic oxidation of 3,3',5,5'-tetramethylbenzidine in the presence of H2O2 to generate a blue product. The enhanced activity is attributed to its more negative potential and larger specific surface of the NCs. Based on these findings, a rapid and ultrasensitive method was developed for the visual and colorimetric determination of H2O2. The method is selective, and the NCs are reusable and long-term stable. The detection limit of H2O2 is 50 nM. Kinetic and active species trapping experiments were performed to elucidate the POx-like mechanism of the NCs. Graphical abstract Schematic presentation of the process of Cu2ZnSn(SxSe1-x)4 nanocrystals catalyzing the oxidation of peroxidase substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2 to induce a typical blue color reaction, which can be applied in colorimetric detection of H2O2.

15.
Anal Bioanal Chem ; 409(23): 5547-5554, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28717898

RESUMO

The thiophene-modified rhodamine 6G (GYJ) has been synthesized as a novel chemosensor. The sensor has sufficiently high selectivity and sensitivity for the detection of Fe3+ and Al3+ ions (M3+) by fluorescence and ultraviolet spectroscopy with a strong ability for anti-interference performance. The binding ratio of M3+-GYJ complex was determined to be 2:1 according to the Job's plot. The binding constants for Fe3+ and Al3+ were calculated to be 3.91 × 108 and 5.26 × 108 M-2, respectively. All these unique features made it particularly favorable for cellular imaging applications. The obvious fluorescence microscopy experiments demonstrated that the probes could contribute to the detection of Fe3+ and Al3+ in related cells and biological organs with satisfying resolution. Graphical abstract GYJ has high selectivity and sensitivity for the detection of Fe(III) and Al(III) with the binding ratio of 2:1.


Assuntos
Alumínio/análise , Compostos Férricos/análise , Corantes Fluorescentes/química , Rodaminas/química , Tiofenos/química , Limite de Detecção , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
16.
Sci Total Environ ; 934: 173072, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38734093

RESUMO

The pollution of deep-sea microplastics has received increasing attention. As a special ecosystem in the deep sea, the cold seep area is of great significance for studying the distribution of microplastics in the deep sea. In this work, the distribution and characteristics of microplastics in seawater, sediments, and shellfish in the Haima cold seep area and the correlation between the characteristics of microplastics in different media and the type of media were studied. Microplastics were found in all three media. The abundance of microplastics in different samples from the Haima cold seep area ranged 1.8-3.8 items/L for the seawater, 11.47-96.8 items/kg (d.w.) for the surface sediments, and 0-5 items/individual (0-0.714 items/g) for the shellfish. The amount of microplastics ingested by shellfish varied among different species. The microplastics in these three media were mainly fibrous, dark-colored, small-sized rayon, polyethylene terephthalate (PET), and polyethylene (PE). In the correlation analysis of microplastic characteristics among the three media, it was found that the characteristics of microplastics in different media in the same area were closely related, and each pair of variables showed a significant positive correlation (P ≤ 0.05). The distinctive geographical conditions would accelerate the interchange of microplastics among various media. Principal component analysis showed that habitat contribute to microplastic feature differences in shellfish. Differences in correlation were observed between the characteristics of shellfish microplastics in different regions and the characteristics of microplastics in surrounding seawater and sediments.


Assuntos
Monitoramento Ambiental , Microplásticos , Água do Mar , Poluentes Químicos da Água , Microplásticos/análise , China , Poluentes Químicos da Água/análise , Água do Mar/química , Sedimentos Geológicos/química , Frutos do Mar/análise , Animais , Plásticos/análise
17.
Nat Commun ; 15(1): 5063, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871708

RESUMO

Levitated diamond particles in high vacuum with internal spin qubits have been proposed for exploring macroscopic quantum mechanics, quantum gravity, and precision measurements. The coupling between spins and particle rotation can be utilized to study quantum geometric phase, create gyroscopes and rotational matter-wave interferometers. However, previous efforts in levitated diamonds struggled with vacuum level or spin state readouts. To address these gaps, we fabricate an integrated surface ion trap with multiple stabilization electrodes. This facilitates on-chip levitation and, for the first time, optically detected magnetic resonance measurements of a nanodiamond levitated in high vacuum. The internal temperature of our levitated nanodiamond remains moderate at pressures below 10-5 Torr. We have driven a nanodiamond to rotate up to 20 MHz (1.2 × 109 rpm), surpassing typical nitrogen-vacancy (NV) center electron spin dephasing rates. Using these NV spins, we observe the effect of the Berry phase arising from particle rotation. In addition, we demonstrate quantum control of spins in a rotating nanodiamond. These results mark an important development in interfacing mechanical rotation with spin qubits, expanding our capacity to study quantum phenomena.

18.
Ultrason Sonochem ; 102: 106749, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38217907

RESUMO

Photocatalytic MoS2 with visible light response is considered as a promising bactericidal material owing to its non-toxicity and high antibacterial efficiency. However, photocatalysts always exist as powder, so it is difficult to settle photocatalysts on the metal surface, which limits their application in aqueous environments. To solve this problem, ultrasound and sodium dodecyl sulfate (SDS) were introduced into the co-deposition process of MoS2 and zinc matrix, so that novel MoS2-Zn coatings were obtained. In this process, ultrasound and SDS strongly promoted the dispersion and adsorption of MoS2 on the co-depositing surfaces. Then MoS2 were proved to be composited into the Zn matrix with effective structures, and the addition of SDS effectively increased the loading content of MoS2 in the MoS2-Zn coatings. Besides, the antibacterial performance of the MoS2-Zn coatings was evaluated with three typical fouling bacteria E.coli, S.aureus and B.wiedmannii. The MoS2-Zn coating showed high and broad-spectrum antibacterial properties with over 98 % inhibition rate against these three bacteria. Furthermore, it is proved that the MoS2-Zn coatings generated superoxide (·O2-) and hydroxyl radicals (·OH) under visible light, which played the dominant and subordinate roles in the antibacterial process, respectively. The MoS2-Zn coatings also showed high antibacterial stability after four "light-dark" cycles. According to the results of the attached bacteria, the MoS2-Zn coatings were considered to effectively repel the living pelagic bacteria instead of killing the attached ones, which was highly environmentally friendly. The obtained MoS2-Zn coatings were considered promising in biofilm inhibiting and marine antifouling fields.


Assuntos
Galvanoplastia , Molibdênio , Dodecilsulfato de Sódio/química , Molibdênio/farmacologia , Molibdênio/química , Antibacterianos/farmacologia , Antibacterianos/química , Zinco/química , Escherichia coli
19.
Anal Chim Acta ; 1304: 342558, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38637055

RESUMO

Quorum sensing signal molecule is an important biomarker released by some microorganisms, which can regulate the adhesion and aggregation of marine microorganisms on the surface of engineering facilities. Thus, it is significant to exploit a convenient method that can effectively monitor the formation and development of marine biofouling. In this work, an advanced photoelectrochemical (PEC) aptamer biosensing platform was established and firstly applied for the rapid and ultrasensitive determination of N-(3-Oxodecanoyl)-l-homoserine lactone (3-O-C10-HL) released from marine fouling microorganism Ponticoccus sp. PD-2. The visible-light-driven Bi2WO6/Bi2S3 heterojunction derived from metal-organic frameworks (MOFs) CAU-17 and self-screened aptamer were employed as the photoactive materials and bioidentification elements, respectively. Appropriate amount of MoS2 quantum dots (QDs) conjugated with single-stranded DNA were introduced by hybridization to enhance the photocurrent response of the PEC biosensor. The self-screening aptamer can specifically recognize 3-O-C10-HL, accompanied by increasing the steric hindrance and forcing MoS2 QDs to leave the electrode surface, resulting in an obvious reduction of photocurrent and achieving a dual-inhibition signal amplification effect. Under the optimized conditions, the photocurrent response of PEC aptasensor was linear with 3-O-C10-HL concentration from 1 nM to 10 µM, and the detection limit was as low as 0.26 nM. The detection strategy also showed a high reproducibility, superior specificity and good stability. This work not only provides a simple, rapid and ultrasensitive PEC aptamer biosensing strategy for monitoring quorum sensing signal molecules in marine biofouling, but also broadens the application of MOFs-based heterojunctions in PEC sensors.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Técnicas Eletroquímicas/métodos , Reprodutibilidade dos Testes , Molibdênio , Percepção de Quorum , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Limite de Detecção
20.
Nanomaterials (Basel) ; 14(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38607155

RESUMO

In this paper, a novel method was proposed for the synthesis of Cu2S on copper mesh via electrolysis in SRB culture medium. It was found that following electrolysis in SRB medium, squamous-like Cu2S arrays were obtained on the copper mesh, and the Cu2S loading contents varied with the electrolyzing parameters. The resultant Cu2S on copper mesh in SRB (CSCM-SRB) with the highest catalytic MB degradation properties was produced by electrolysis at 3.75 mA/cm2 for 900 s. The optimized MB-degrading conditions were determined to be 1.2 cm2/mL CSCM-SRB with 0.05 M H2O2 at 35 °C when pH = 6, under which the degradation of MB reached over 99% after 120 min of reaction. Disinfecting properties was also proven by antibacterial tests, revealing that an almost 100% antibacterial rate against E. coli was obtained after 8 min. The organic compounds produced by SRB adsorbed on CSCM-SRB strongly promoted the degradation of MB. Furthermore, possible Fenton-like mechanisms of CSCM-SRB were proposed, illustrating that ·O2-, ·OH, and 1O2 acted as the main functional species during Fenton-like reactions, leading to effective MB degradation and high antibacterial properties. Finally, a simple device for wastewater treatment was designed, providing possible applications in real environments.

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