Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 107
Filtrar
1.
Food Chem ; 463(Pt 4): 141538, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39388873

RESUMO

Primulina plants native to karst regions are exceptionally rich in calcium and have been developed into high­calcium leafy vegetables. However, limited knowledge of their metabolites, taste characteristics, and potential medicinal value restricts further genetic improvements. This study conducted a comprehensive analysis on three breeding species of Primulina vegetables. Common garden experiment demonstrated significant calcium enrichment capability, with calcium content ranging from 204.45 to 391.52 mg/100 g. Through widely-targeted metabolomics, 1121 metabolites were identified within these Primulina vegetables. Furthermore, comparative analysis identified 976 differentially accumulated metabolites across nine comparison groups, driven mainly by flavonoids, phenolic acids, and lipids. Integration of electronic tongue analysis and metabolomics revealed taste profiles and identified 17 key candidate compounds related to taste. Based on network pharmacology analysis, 32 active ingredients were found in Primulina vegetables, which highlighted potential medicinal value. These findings provide a data-driven foundation for breeding programs aimed at enhancing nutritional and flavor traits.

2.
Microsyst Nanoeng ; 10(1): 145, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39396959

RESUMO

Navigating toward destinations with rewards is a common behavior among animals. The ventral tegmental area (VTA) has been shown to be responsible for reward coding and reward cue learning, and its response to other variables, such as kinematics, has also been increasingly studied. These findings suggest a potential relationship between animal navigation behavior and VTA activity. However, the deep location and small volume of the VTA pose significant challenges to the precision of electrode implantation, increasing the uncertainty of measurement results during animal navigation and thus limiting research on the role of the VTA in goal-directed navigation. To address this gap, we innovatively designed and fabricated low-curvature microelectrode arrays (MEAs) via a novel backside dry etching technique to release residual stress. Histological verification confirmed that low-curvature MEAs indeed improved electrode implantation precision. These low-curvature MEAs were subsequently implanted into the VTA of the rats to observe their electrophysiological activity in a freely chosen modified T-maze. The results of the behavioral experiments revealed that the rats could quickly learn the reward probability corresponding to the left and right paths and that VTA neurons were deeply involved in goal-directed navigation. Compared with those in no-reward trials, VTA neurons in reward trials presented a significantly greater firing rate and larger local field potential (LFP) amplitude during the reward-consuming period. Notably, we discovered place fields mapped by VTA neurons, which disappeared or were reconstructed with changes in the path-outcome relationship. These results provide new insights into the VTA and its role in goal-directed navigation. Our designed and fabricated low-curvature microelectrode arrays can serve as a new device for precise deep brain implantation in the future.

3.
J Zhejiang Univ Sci B ; 25(10): 803-823, 2024 Feb 12.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-39420519

RESUMO

Deep brain stimulation (DBS), including optical stimulation and electrical stimulation, has been demonstrated considerable value in exploring pathological brain activity and developing treatments for neural disorders. Advances in DBS microsystems based on implantable microelectrode array (MEA) probes have opened up new opportunities for closed-loop DBS (CL-DBS) in situ. This technology can be used to detect damaged brain circuits and test the therapeutic potential for modulating the output of these circuits in a variety of diseases simultaneously. Despite the success and rapid utilization of MEA probe-based CL-DBS microsystems, key challenges, including excessive wired communication, need to be urgently resolved. In this review, we considered recent advances in MEA probe-based wireless CL-DBS microsystems and outlined the major issues and promising prospects in this field. This technology has the potential to offer novel therapeutic options for psychiatric disorders in the future.


Assuntos
Estimulação Encefálica Profunda , Microeletrodos , Tecnologia sem Fio , Estimulação Encefálica Profunda/instrumentação , Estimulação Encefálica Profunda/métodos , Humanos , Tecnologia sem Fio/instrumentação , Eletrodos Implantados , Encéfalo , Animais
4.
Biosens Bioelectron ; 267: 116837, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39369514

RESUMO

Microelectrode arrays (MEAs) are pivotal brain-machine interface devices that facilitate in situ and real-time detection of neurophysiological signals and neurotransmitter data within the brain. These capabilities are essential for understanding neural system functions, treating brain disorders, and developing advanced brain-machine interfaces. To enhance the performance of MEAs, this study developed a crosslinked hydrogel coating of calcium alginate (CA) and chitosan (CS) loaded with the anti-inflammatory drug dexamethasone sodium phosphate (DSP). By modifying the MEAs with this hydrogel and various conductive nanomaterials, including platinum nanoparticles (PtNPs) and poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT: PSS), the electrical properties and biocompatibility of the electrodes were optimized. The hydrogel coating matches the mechanical properties of brain tissue more effectively and, by actively releasing anti-inflammatory drugs, significantly reduces post-implantation tissue inflammation, extends the electrodes' lifespan, and enhances the quality of neural activity detection. Additionally, this modification ensures high sensitivity and specificity in the detection of dopamine (DA), displaying high-quality dual-mode neural activity during in vivo testing and revealing significant functional differences between neuron types under various physiological states (anesthetized and awake). Overall, this study showcases the significant application value of bioactive hydrogels as excellent nanobiointerfaces and drug delivery carriers for long-term neural monitoring. This approach has the potential to enhance the functionality and acceptance of brain-machine interface devices in medical practice and has profound implications for future neuroscience research and the development of strategies for treating neurological diseases.

5.
Anal Bioanal Chem ; 416(26): 5815-5825, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39212699

RESUMO

The preparation of histology slides is a critical step in histopathology, and poor-quality histology slides with weak adhesion of tissue sections to the substrate often affect diagnostic accuracy and sometimes lead to diagnostic failure due to tissue section detachment. This issue has been of concern and some methods have been proposed to enhance tissue-substrate adhesion. Unfortunately, quantitative analysis of the adhesion between tissue sections and glass slides is still challenging. In this work, the adhesion of mouse brain tissue sections on gold-coated glass slides was analyzed using a laboratory-fabricated hyperspectral surface plasmon resonance microscopy (HSPRM) system that enabled single-pixel spectral SPR sensing and provided two-dimensional (2D) distribution of resonance wavelengths (RWs). The existence of the nanoscale water gap between the tissue section and the substrate was verified by fitting the RW measured in each pixel using the five-layer Fresnel reflection model. In addition, a 2D image of the tissue-substrate adhesion distance (AD) was obtained from the measured 2D distribution of RWs. The results showed that tissue-substrate AD was 20-35 nm in deionized water and 4-24 nm in saline solution. The HSPRM system used in this work has a wide wavelength range of 400-1000 nm and can perform highly sensitive and label-free detection over a large dynamic detection range with high spectral and spatial resolutions, showing significant potential applications in stain-free tissue imaging, quantitative analysis of tissue-substrate adhesion, accurate identification of tumor cells, and rapid histopathological diagnosis.


Assuntos
Ressonância de Plasmônio de Superfície , Ressonância de Plasmônio de Superfície/métodos , Animais , Camundongos , Microscopia/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/citologia , Ouro/química
6.
ACS Appl Mater Interfaces ; 16(34): 44538-44548, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39072533

RESUMO

Temperature has a profound influence on various neuromodulation processes and has emerged as a focal point. However, the effects of acute environmental temperature fluctuations on cultured cortical networks have been inadequately elucidated. To bridge this gap, we have developed a brain-on-a-chip platform integrating cortical networks and electrodeposited Pt/Ir modified microelectrode arrays (MEAs) with 3D-printed bear-shaped triple chambers, facilitating control of temperature transients. This innovative system administers thermal stimuli while concurrently monitoring neuronal activity, including spikes and local field potentials, from 60 microelectrodes (diameter: 30 µm; impedance: 9.34 ± 1.37 kΩ; and phase delay: -45.26 ± 2.85°). Temperature transitions of approximately ±10 °C/s were applied to cortical networks on MEAs via in situ perfusion within the triple chambers. Subsequently, we examined the spatiotemporal dynamics of the brain-on-a-chip under temperature regulation at both the group level (neuronal population) and their interactions (network dynamics) and the individual level (cellular activity). Specifically, we found that after the temperature reduction neurons enhanced the overall information transmission efficiency of the network through synchronous firing to compensate for the decreased efficiency of single-cell level information transmission, in contrast to temperature elevation. By leveraging the integration of high-performance MEAs with perfusion chambers, this investigation provides a comprehensive understanding of the impact of temperature on the spatiotemporal dynamics of neural networks, thereby facilitating future exploration of the intricate interplay between temperature and brain function.


Assuntos
Microeletrodos , Neurônios , Platina , Temperatura , Animais , Platina/química , Neurônios/fisiologia , Irídio/química , Córtex Cerebral/fisiologia , Galvanoplastia/métodos , Ratos
7.
ACS Appl Mater Interfaces ; 16(24): 31677-31686, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38833518

RESUMO

Due to their compact size and exceptional sensitivity at room temperature, magnetoresistance (MR) sensors have garnered considerable interest in numerous fields, particularly in the detection of weak magnetic signals in biological systems. The "magnetrodes", integrating MR sensors with needle-shaped Si-based substrates, are designed to be inserted into the brain for local magnetic field detection. Although recent research has predominantly focused on giant magnetoresistance (GMR) sensors, tunnel magnetoresistance (TMR) sensors exhibit a significantly higher sensitivity. In this study, we introduce TMR-based magnetrodes featuring TMR sensors at both the tip and midsection of the probe, enabling detection of local magnetic fields at varied spatial positions. To enhance detectivity, we designed and fabricated magnetrodes with varied aspect ratios of the free layer, incorporating diverse junction shapes, quantities, and serial arrangements. Utilizing a custom-built magnetotransport and noise measurement system for characterization, our TMR-based magnetrode demonstrates a limit of detection (LOD) of 300pT/Hz at 1 kHz. This implies that neuronal spikes can be distinguished with minimal averaging, thereby facilitating the elucidation of their magnetic properties.

8.
ACS Sens ; 9(6): 2705-2727, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38843307

RESUMO

The ultrasensitive recognition of biomarkers plays a crucial role in the precise diagnosis of diseases. Graphene-based field-effect transistors (GFET) are considered the most promising devices among the next generation of biosensors. GFET biosensors possess distinct advantages, including label-free, ease of integration and operation, and the ability to directly detect biomarkers in liquid environments. This review summarized recent advances in GFET biosensors for biomarker detection, with a focus on interface functionalization. Various sensitivity-enhancing strategies have been overviewed for GFET biosensors, from the perspective of optimizing graphene synthesis and transfer methods, refinement of surface functionalization strategies for the channel layer and gate electrode, design of biorecognition elements and reduction of nonspecific adsorption. Further, this review extensively explores GFET biosensors functionalized with antibodies, aptamers, and enzymes. It delves into sensitivity-enhancing strategies employed in the detection of biomarkers for various diseases (such as cancer, cardiovascular diseases, neurodegenerative disorders, infectious viruses, etc.) along with their application in integrated microfluidic systems. Finally, the issues and challenges in strategies for the modulation of biosensing interfaces are faced by GFET biosensors in detecting biomarkers.


Assuntos
Biomarcadores , Técnicas Biossensoriais , Grafite , Transistores Eletrônicos , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Grafite/química , Biomarcadores/análise , Humanos
9.
ACS Nano ; 18(26): 17162-17174, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38902594

RESUMO

Although in vitro neuronal network models hold great potential for advancing neuroscience research, with the capacity to provide fundamental insights into mechanisms underlying neuronal functions, the dynamics of cell communication within such networks remain poorly understood. Here, we develop a customizable, polymer modified three-dimensional gold microelectrode array with sufficient stability for high signal-to-noise, long-term, neuronal recording of cultured networks. By using directed spatial and temporal patterns of electrical stimulation of cells to explore synaptic-based communication, we monitored cell network dynamics over 3 weeks, quantifying communication capability using correlation heatmaps and mutual information networks. Analysis of synaptic delay and signal speed between cells enabled us to establish a communication connectivity model. We anticipate that our discoveries of the dynamic changes in communication across the neuronal network will provide a valuable tool for future studies in understanding health and disease as well as in developing effective platforms for evaluating therapies.


Assuntos
Ouro , Microeletrodos , Rede Nervosa , Neurônios , Ouro/química , Animais , Neurônios/fisiologia , Rede Nervosa/fisiologia , Comunicação Celular , Ratos , Células Cultivadas
10.
Adv Sci (Weinh) ; 11(29): e2401670, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38828784

RESUMO

Hippocampal CA1 neurons show intense firing at specific spatial locations, modulated by isolated landmarks. However, the impact of real-world scene transitions on neuronal activity remains unclear. Moreover, long-term neural recording during movement challenges device stability. Conventional rigid-based electrodes cause inflammatory responses, restricting recording durations. Inspired by the jellyfish tentacles, the multi-conductive layer ultra-flexible microelectrode arrays (MEAs) are developed. The tentacle MEAs ensure stable recordings during movement, thereby enabling the discovery of soft boundary neurons. The soft boundary neurons demonstrate high-frequency firing that aligns with the boundaries of scene transitions. Furthermore, the localization ability of soft boundary neurons improves with more scene transition boundaries, and their activity decreases when these boundaries are removed. The innovation of ultra-flexible, high-biocompatible tentacle MEAs improves the understanding of neural encoding in spatial cognition. They offer the potential for long-term in vivo recording of neural information, facilitating breakthroughs in the understanding and application of brain spatial navigation mehanisms.


Assuntos
Região CA1 Hipocampal , Microeletrodos , Neurônios , Animais , Neurônios/fisiologia , Região CA1 Hipocampal/fisiologia , Região CA1 Hipocampal/citologia , Ratos , Masculino , Desenho de Equipamento/métodos
11.
Cyborg Bionic Syst ; 5: 0125, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841725

RESUMO

Depression is a common and severely debilitating neuropsychiatric disorder. Multiple studies indicate a strong correlation between the occurrence of immunological inflammation and the presence of depression. The basolateral amygdala (BLA) is crucial in the cognitive and physiological processing and control of emotion. However, due to the lack of detection tools, the neural activity of the BLA during depression is not well understood. In this study, a microelectrode array (MEA) based on the shape and anatomical location of the BLA in the brain was designed and manufactured. Rats were injected with lipopolysaccharide (LPS) for 7 consecutive days to induce depressive behavior. We used the MEA to detect neural activity in the BLA before modeling, during modeling, and after LPS administration on 7 consecutive days. The results showed that after LPS treatment, the spike firing of neurons in the BLA region of rats gradually became more intense, and the local field potential power also increased progressively. Further analysis revealed that after LPS administration, the spike firing of BLA neurons was predominantly in the theta rhythm, with obvious periodic firing characteristics appearing after the 7 d of LPS administration, and the relative power of the local field potential in the theta band also significantly increased. In summary, our results suggest that the enhanced activity of BLA neurons in the theta band is related to the depressive state of rats, providing valuable guidance for research into the neural mechanisms of depression.

12.
Cyborg Bionic Syst ; 5: 0123, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38784125

RESUMO

The globus pallidus internus (GPi) was considered a common target for stimulation in Parkinson's disease (PD). Located deep in the brain and of small size, pinpointing it during surgery is challenging. Multi-channel microelectrode arrays (MEAs) can provide micrometer-level precision functional localization, which can maximize the surgical outcome. In this paper, a 64-channel MEA modified by platinum nanoparticles with a detection site impedance of 61.1 kΩ was designed and prepared, and multiple channels could be synchronized to cover the target brain region and its neighboring regions so that the GPi could be identified quickly and accurately. The results of the implant trajectory indicate that, compared to the control side, there is a reduction in local field potential (LFP) power in multiple subregions of the upper central thalamus on the PD-induced side, while the remaining brain regions exhibit an increasing trend. When the MEA tip was positioned at 8,700 µm deep in the brain, the various characterizations of the spike signals, combined with the electrophysiological characteristics of the ß-segmental oscillations in PD, enabled MEAs to localize the GPi at the single-cell level. More precise localization could be achieved by utilizing the distinct characteristics of the internal capsule (ic), the thalamic reticular nucleus (Rt), and the peduncular part of the lateral hypothalamus (PLH) brain regions, as well as the relative positions of these brain structures. The MEAs designed in this study provide a new detection method and tool for functional localization of PD targets and PD pathogenesis at the cellular level.

13.
ACS Sens ; 9(6): 2877-2887, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38779969

RESUMO

Precise assessment of wakefulness states during sevoflurane anesthesia and timely arousal are of paramount importance to refine the control of anesthesia. To tackle this issue, a bidirectional implantable microelectrode array (MEA) is designed with the capability to detect electrophysiological signal and perform in situ deep brain stimulation (DBS) within the dorsomedial hypothalamus (DMH) of mice. The MEA, modified with platinum nanoparticles/IrOx nanocomposites, exhibits exceptional characteristics, featuring low impedance, minimal phase delay, substantial charge storage capacity, high double-layer capacitance, and longer in vivo lifetime, thereby enhancing the sensitivity of spike firing detection and electrical stimulation (ES) effectiveness. Using this MEA, sevoflurane-inhibited neurons and sevoflurane-excited neurons, together with changes in the oscillation characteristics of the local field potential within the DMH, are revealed as indicative markers of arousal states. During the arousal period, varying-frequency ESs are applied to the DMH, eliciting distinct arousal effects. Through in situ detection and stimulation, the disparity between these outcomes can be attributed to the influence of DBS on different neurons. These advancements may further our understanding of neural circuits and their potential applications in clinical contexts.


Assuntos
Estimulação Encefálica Profunda , Microeletrodos , Sevoflurano , Animais , Sevoflurano/farmacologia , Camundongos , Estimulação Encefálica Profunda/instrumentação , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Masculino , Anestésicos Inalatórios , Estimulação Elétrica , Platina/química , Camundongos Endogâmicos C57BL
14.
Front Bioeng Biotechnol ; 12: 1376151, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38633666

RESUMO

The striatum plays a crucial role in studying epilepsy, as it is involved in seizure generation and modulation of brain activity. To explore the complex interplay between the striatum and epilepsy, we engineered advanced microelectrode arrays (MEAs) specifically designed for precise monitoring of striatal electrophysiological activities in rats. These observations were made during and following seizure induction, particularly three and 7 days post-initial modeling. The modification of graphene oxide (GO)/poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS)/platinu-m nanoparticles (PtNPs) demonstrated a marked reduction in impedance (10.5 ± 1.1 kΩ), and maintained exceptional stability, with impedance levels remaining consistently low (23 kΩ) even 14 days post-implantation. As seizure intensity escalated, we observed a corresponding increase in neuronal firing rates and local field potential power, with a notable shift towards higher frequency peaks and augmented inter-channel correlation. Significantly, during the grand mal seizures, theta and alpha bands became the dominant frequencies in the local field potential. Compared to the normal group, the spike firing rates on day 3 and 7 post-modeling were significantly higher, accompanied by a decreased firing interval. Power in both delta and theta bands exhibited an increasing trend, correlating with the duration of epilepsy. These findings offer valuable insights into the dynamic processes of striatal neural activity during the initial and latent phases of temporal lobe epilepsy and contribute to our understanding of the neural mechanisms underpinning epilepsy.

15.
Adv Mater ; 36(27): e2314310, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38655719

RESUMO

The precise delivery of anti-seizure medications (ASM) to epileptic loci remains the major challenge to treat epilepsy without causing adverse drug reactions. The unprovoked nature of epileptic seizures raises the additional need to release ASMs in a spatiotemporal controlled manner. Targeting the oxidative stress in epileptic lesions, here the reactive oxygen species (ROS) induced in situ supramolecular assemblies that synergized bioorthogonal reactions to deliver inhibitory neurotransmitter (GABA) on-demand, are developed. Tetrazine-bearing assembly precursors undergo oxidation and selectively self-assemble under pathological conditions inside primary neurons and mice brains. Assemblies induce local accumulation of tetrazine in the hippocampus CA3 region, which allows the subsequent bioorthogonal release of inhibitory neurotransmitters. For induced acute seizures, the sustained release of GABA extends the suppression than the direct supply of GABA. In the model of permanent damage of CA3, bioorthogonal ligation on assemblies provides a reservoir of GABA that behaves prompt release upon 365 nm irradiation. Incorporated with the state-of-the-art microelectrode arrays, it is elucidated that the bioorthogonal release of GABA shifts the neuron spike waveforms to suppress seizures at the single-neuron precision. The strategy of in situ supramolecular assemblies-directed bioorthogonal prodrug activation shall be promising for the effective delivery of ASMs to treat epilepsy.


Assuntos
Hipocampo , Neurotransmissores , Espécies Reativas de Oxigênio , Convulsões , Ácido gama-Aminobutírico , Animais , Convulsões/tratamento farmacológico , Convulsões/metabolismo , Camundongos , Neurotransmissores/metabolismo , Neurotransmissores/química , Ácido gama-Aminobutírico/química , Ácido gama-Aminobutírico/metabolismo , Hipocampo/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Neurônios/metabolismo , Liberação Controlada de Fármacos , Região CA3 Hipocampal/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-38656860

RESUMO

In neurodegenerative disorders, neuronal firing patterns and oscillatory activity are remarkably altered in specific brain regions, which can serve as valuable biomarkers for the identification of deep brain regions. The subthalamic nucleus (STN) has been the primary target for DBS in patients with Parkinson's disease (PD). In this study, changes in the spike firing patterns and spectral power of local field potentials (LFPs) in the pre-STN (zona incerta, ZI) and post-STN (cerebral peduncle, cp) regions were investigated in PD rats, providing crucial evidence for the functional localization of the STN. Sixteen-channel microelectrode arrays (MEAs) with sites distributed at different depths and widths were utilized to record neuronal activities. The spikes in the STN exhibited higher firing rates than those in the ZI and cp. Furthermore, the LFP power in the delta band in the STN was the greatest, followed by that in the ZI, and was greater than that in the cp. Additionally, increased LFP power was observed in the beta bands in the STN. To identify the best performing classification model, we applied various convolutional neural networks (CNNs) based on transfer learning to analyze the recorded raw data, which were processed using the Gram matrix of the spikes and the fast Fourier transform of the LFPs. The best transfer learning model achieved an accuracy of 95.16%. After fusing the spike and LFP classification results, the time precision for processing the raw data reached 500 ms. The pretrained model, utilizing raw data, demonstrated the feasibility of employing transfer learning for training models on neural activity. This approach highlights the potential for functional localization within deep brain regions.


Assuntos
Estimulação Encefálica Profunda , Microeletrodos , Ratos Sprague-Dawley , Núcleo Subtalâmico , Núcleo Subtalâmico/fisiopatologia , Animais , Ratos , Masculino , Modelos Animais de Doenças , Doença de Parkinson/fisiopatologia , Doença de Parkinson/reabilitação , Potenciais de Ação/fisiologia , Algoritmos , Sistemas Computacionais , Transtornos Parkinsonianos/fisiopatologia , Transtornos Parkinsonianos/reabilitação , Aprendizado de Máquina
17.
Biosens Bioelectron ; 253: 116168, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38452571

RESUMO

Burst and local field potential (LFP) are fundamental components of brain activity, representing fast and slow rhythms, respectively. Understanding the intricate relationship between burst and LFP is crucial for deciphering the underlying mechanisms of brain dynamics. In this study, we fabricated high-performance microelectrode arrays (MEAs) using the SWCNTs/PEDOT:PSS nanocomposites, which exhibited favorable electrical properties (low impedance: 12.8 ± 2.44 kΩ) and minimal phase delay (-11.96 ± 1.64°). These MEAs enabled precise exploration of the burst-LFP interaction in cultured cortical networks. After a 14-day period of culture, we used the MEAs to monitor electrophysiological activities and revealed a time-locking relationship between burst and LFP, indicating the maturation of the neural network. To further investigate this relationship, we modulated burst firing patterns by treating the neural culture with increasing concentrations of glycine. The results indicated that glycine effectively altered burst firing patterns, with both duration and spike count increasing as the concentration rose. This was accompanied by an enhanced level of time-locking between burst and LFP but a decrease in synchrony among neurons. This study not only highlighted the pivotal role of SWCNTs/PEDOT:PSS-modified MEAs in elucidating the interaction between burst and LFP, bridging the gap between slow and fast brain rhythms in vitro but also provides valuable insights into the potential therapeutic strategies targeting neurological disorders associated with abnormal rhythm generation.


Assuntos
Técnicas Biossensoriais , Nanocompostos , Microeletrodos , Neurônios/fisiologia , Glicina
18.
J Zhejiang Univ Sci B ; : 1-21, 2024 Feb 12.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38423536

RESUMO

Deep brain stimulation (DBS), including optical stimulation and electrical stimulation, has been demonstrated considerable value in exploring pathological brain activity and developing treatments for neural disorders. Advances in DBS microsystems based on implantable microelectrode array (MEA) probes have opened up new opportunities for closed-loop DBS (CL-DBS) in situ. This technology can be used to detect damaged brain circuits and test the therapeutic potential for modulating the output of these circuits in a variety of diseases simultaneously. Despite the success and rapid utilization of MEA probe-based CL-DBS microsystems, key challenges, including excessive wired communication, need to be urgently resolved. In this review, we considered recent advances in MEA probe-based wireless CL-DBS microsystems and outlined the major issues and promising prospects in this field. This technology has the potential to offer novel therapeutic options for psychiatric disorders in the future.

19.
Front Bioeng Biotechnol ; 12: 1347625, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357703

RESUMO

17ß-Estradiol (E2) is a critical sex steroid hormone, which has significant effects on the endocrine systems of both humans and animals. E2 is also believed to play neurotrophic and neuroprotective roles in the brain. Biosensors present a powerful tool to detect E2 because of their small, efficient, and flexible design. Furthermore, Biosensors can quickly and accurately obtain detection results with only a small sampling amount, which greatly meets the detection of the environment, food safety, medicine safety, and human body. This review focuses on previous studies of biosensors for detecting E2 and divides them into non-biometric sensors, enzyme biosensors, antibody biosensors, and aptamer biosensors according to different bioreceptors. The advantages, disadvantages, and design points of various bioreceptors for E2 detection are analyzed and summarized. Additionally, applications of different bioreceptors of E2 detection are presented and highlight the field of environmental monitoring, food and medicine safety, and disease detection in recent years. Finally, the development of E2 detection by biosensor is prospected.

20.
Molecules ; 29(2)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276613

RESUMO

The specific and sensitive detection of 17ß-estradiol (E2) is critical for diagnosing and treating numerous diseases, and aptamers have emerged as promising recognition probes for developing detection platforms. However, traditional long-sequence E2 aptamers have demonstrated limited clinical performance due to redundant structures that can affect their stability and recognition ability. There is thus an urgent need to further optimize the structure of the aptamer to build an effective detection platform for E2. In this work, we have designed a novel short aptamer that retains the key binding structure of traditional aptamers to E2 while eliminating the redundant structures. The proposed aptamer was evaluated for its binding properties using microscale thermophoresis, a gold nanoparticle-based colorimetric method, and electrochemical assays. Our results demonstrate that the proposed aptamer has excellent specific recognition ability for E2 and a high affinity with a dissociation constant of 92 nM. Moreover, the aptamer shows great potential as a recognition probe for constructing a highly specific and sensitive clinical estradiol detection platform. The aptamer-based electrochemical sensor enabled the detection of E2 with a linear range between 5 pg mL-1 and 10 ng mL-1 (R2 = 0.973), and the detection capability of a definite low concentration level was 5 pg mL-1 (S/N = 3). Overall, this novel aptamer holds great promise as a valuable tool for future studies on the role of E2 in various physiological and pathological processes and for developing sensitive and specific diagnostic assays for E2 detection in clinical applications.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Aptâmeros de Nucleotídeos/química , Nanopartículas Metálicas/química , Estradiol/metabolismo , Ouro/química , Colorimetria , Técnicas Biossensoriais/métodos , Limite de Detecção
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA