Dynamic and Label-Free Sensing of Cardiomyocyte Responses to Nanosized Vesicles for Cardiac Oxidative Stress Injury Therapy.

Cardiac oxidative stress is a significant phenotype of myocardial infarction disease, a leading cause of global health threat. There is an urgent need to develop innovative therapies. Nanosized extracellular vesicle (nEV)-based therapy shows promise, yet real-time monitoring of cardiomyocyte responses to nEVs remains a challenge. In this study, a dynamic and label-free cardiomyocyte biosensing system using microelectrode arrays (MEAs) was constructed. Cardiomyocytes were cultured on MEA devices for electrophysiological signal detection and treated with nEVs from E. coli, gardenia, HEK293 cells, and mesenchymal stem cells (MSC), respectively. E. coli-nEVs and gardenia-nEVs induced severe paroxysmal fibrillation, revealing distinct biochemical communication compared to MSC-nEVs. Principal component analysis identified variations and correlations between nEV types. MSC-nEVs enhanced recovery without inducing arrhythmias in a H2O2-induced oxidative stress injury model. This study establishes a fundamental platform for assessing biochemical communication between nEVs and cardiomyocytes, offering new avenues for understanding nEVs' functions in the cardiovascular system.

Biohybrid Tongue for Evaluation of Taste Interaction between Sweetness and Sourness.

The past decade has witnessed tremendous progress achieved in taste research, while few studies focus on interactions among taste compounds. Indeed, sweeteners and acidulants are commonly used food additives, and sweet-sour mixtures always provide improved tastes. For example, sensory studies have shown that sourness suppresses sweetness. However, the degree of sweetness suppression by sourness is difficult to evaluate quantitatively and objectively. Therefore, we propose a biohybrid tongue that is constructed by integrating mammalian gustatory epithelium with a microelectrode array chip. The taste quality and intensity information is coded in time-frequency patterns of local field potential. Different response patterns evoked by sweet and sour stimuli are observed, and the response is dose-dependent. Then, interaction effects of sourness against sweetness are quantified. The results indicate that suppression of sweetness by sourness occurs by increasing sourness concentrations. In summary, this study provides a powerful new tool for quantitative evaluation of sweet, sour, and their binary taste interactions that mimic the mammalian taste system.

An in vivo bioelectronic nose for possible quantitative evaluation of odor masking using M/T cell spatial response patterns.

Odor masking is a prominent phenomenon in the biological olfactory perception system. It has been applied in industry and daily life to develop masking agents to reduce or even eliminate the adverse effects of unpleasant odors. However, it is challenging to assess the odor masking efficiency with traditional gas sensors. Here, we took advantage of the olfactory perception system of an animal to develop a system for the evaluation and quantification of odor masking based on an in vivo bioelectronic nose. The linear decomposition method was used to extract the features of the spatial response pattern of the mitral/tufted (M/T) cell population of the olfactory bulb of a rat to monomolecular odorants and their binary mixtures. Finally, the masking intensity was calculated to quantitatively measure the degree of interference of one odor to another in the biological olfactory system. Compared with the human sensory evaluation reported in a previous study, the trend of masking intensity obtained with this system positively correlated with the human olfactory system. The system could quantitatively analyze the masking efficiency of masking agents, as well as assist in the development of new masking agents or flavored food in odor or food companies.

Synthesis of green magnetic molecularly imprinted polymers for selective extraction of rifaximin in milk samples.

In this study, a new analytical method was developed using magnetic molecularly imprinted polymers (MMIPs) by employing eco-friendly supramolecular ternary deep eutectic solvents to synthesize these MMIPs for selective extraction of rifaximin. The characterization analysis and adsorption affinity investigation were conducted. The results showed fast adsorption (15 min) with high adsorption capacity (43.20 mg g-1) and selectivity for rifaximin. Various extraction parameters were optimized, achieving recoveries ranging from 86.67% to 99.47% in spiked milk samples using high-performance liquid chromatography (HPLC). The detection and quantification limits were 0.01 mg L-1 and 0.03 mg L-1, respectively. The method exhibited low RSDs (<4.70%) and excellent selectivity, with MMIPs reusable up to seven times with only a 10% performance loss. This study proposes a convenient and reliable method for trace-level rifaximin extraction from milk using eco-friendly MMIPs.

A dual-mode, image-enhanced, miniaturized microscopy system for incubator-compatible monitoring of live cells.

Imaging live cells under stable culture conditions is essential to investigate cell physiological activities and proliferation. To achieve this goal, typically, a specialized incubation chamber that creates desired culture conditions needs to be incorporated into a microscopy system to perform cell monitoring. However, such imaging systems are generally large and costly, hampering their wide applications. Recent advances in the field of miniaturized microscopy systems have enabled incubator cell monitoring, providing a hospitable environment for live cells. Although these systems are more cost-effective, they are usually limited in imaging modalities and spatial temporal resolution. Here, we present a dual-mode, image-enhanced, miniaturized microscopy system (termed MiniCube) for direct monitoring of live cells inside incubators. MiniCube enables both bright field imaging and fluorescence imaging with single-cell spatial resolution and sub-second temporal resolution. Moreover, this system can also perform cell monitoring inside the incubator with tunable time scales ranging from a few seconds to days. Meanwhile, automatic cell segmentation and image enhancement are realized by the proposed data analysis pipeline of this system, and the signal-to-noise ratio (SNR) of acquired data is significantly improved using a deep learning based image denoising algorithm. Image data can be acquired with 5 times lower light exposure while maintaining comparable SNR. The versatility of this miniaturized microscopy system lends itself to various applications in biology studies, providing a practical platform and method for studying live cell dynamics within the incubator.

Near-infrared-triggered plasmonic regulation and cardiomyocyte-based biosensing system for in vitro bradyarrhythmia treatment.

Bradyarrhythmia, a life-threatening cardiovascular disease, is an increasing burden for the healthcare system. Currently, surgery, implanted device, and drug are introduced to treat the bradyarrhythmia in clinical practice. However, these conventional therapeutic strategies suffer from the invasive surgery, power supply, or drug side effect, respectively, hence developing the alternative therapeutic strategy is necessarily imperative. Here, a convenient and effective strategy to treat the bradyarrhythmia is proposed using near-infrared-triggered Au nanorod (NR) based plasmonic photothermal effect (PPE). Moreover, electrophysiology of cardiomyocytes is dynamically monitored by the integrated biosensing-regulating system during and after the treatment. Cardiomyocyte-based bradyarrhythmia recover rhythmic for a long time by regulating plasmonic photothermal effect. Furthermore, the regulatory mechanism is qualitatively investigated to verify the significant thermal stimulation in the recovery process. This study establishes a reliable platform for long-term recording and evaluation of mild photothermal therapy for bradyarrhythmia in vitro, offering an efficient and non-invasive strategy for the potential clinical applications.

Elevating intracellular action potential recording in cardiomyocytes: A precision-enhanced and biosafe single-pulse electroporation system.

Action potentials play a pivotal role in diverse cardiovascular physiological mechanisms. A comprehensive understanding of these intricate mechanisms necessitates a high-fidelity intracellular electrophysiological investigative approach. The amalgamation of micro-/nano-electrode arrays and electroporation confers substantial advantages in terms of high-resolution intracellular recording capabilities. Nonetheless, electroporation systems typically lack precise control, and commonly employed electroporation modes, involving tailored sequences, may escalate cellular damage and perturbation of normal physiological functions due to the multiple or higher-intensity electrical pulses. In this study, we developed an innovative electrophysiological biosensing system customized to facilitate precise single-pulse electroporation. This advancement serves to achieve optimal and uninterrupted intracellular action potential recording within cardiomyocytes. The refinement of the single-pulse electroporation technique is realized through the integration of the electroporation and assessment biosensing system, thereby ensuring a consistent and reliable means of achieving stable intracellular access. Our investigation has unveiled that the optimized single-pulse electroporation technique not only maintains robust biosafety standards but also enables the continuous capture of intracellular electrophysiological signals across an expansive three-day period. The universality of this biosensing system, adaptable to various micro/nano devices, furnishes real-time analysis and feedback concerning electroporation efficacy, guaranteeing the sustained, secure, and high-fidelity acquisition of intracellular data, thereby propelling the field of cardiovascular electrophysiological research.

Multimodal spatiotemporal monitoring of basal stem cell-derived organoids reveals progression of olfactory dysfunction in Alzheimer's disease.

Olfactory dysfunction (OD) is a highly prevalent symptom and an early sign of neurodegenerative diseases in humans. However, the roles of peripheral olfactory system in disease progression and the mechanisms behind neurodegeneration remain to be studied. Olfactory epithelium (OE) organoid is an ideal model to study pathophysiology in vitro, yet the reliance on 3D culture condition limits continual in situ monitoring of organoid development. Here, we combined impedance biosensors and live imaging for real-time spatiotemporal analysis of OE organoids morphological and physiological features during Alzheimer's disease (AD) progression. The impedance measurements showed that organoids generated from basal stem cells of APP/PS1 transgenic mice had lower proliferation rate than that from wild-type mice. In concert with the biosensor measurements, live imaging enabled to visualize the spatial and temporal dynamics of organoid morphology. Abnormal protein aggregation and accumulation, including amyloid plaques and neurofibrillary tangles, was found in AD organoids and increased as disease progressed. This multimodal in situ bioelectrical measurement and imaging provide a new platform for investigating onset mechanisms of OD, which would shed new light on early diagnosis and treatment of neurodegenerative disease.

A smart tablet-phone-based high-performance pancreatic cancer cell biosensing system for drug screening.

Exploring more efficient pancreatic cancer drug screening platforms is of significant importance for accelerating the drug development process. In this study, we developed a high-sensitivity bioluminescence system based on smartphones and smart tablets, and constructed a pancreatic cancer drug screening platform (PCDSP) by combining the pancreatic cancer cell sensing model (PCCSM) on the multiwell plates (MTP). A smart tablet was used as the light source and a smartphone as the colorimetric sensing device. The smartphone dynamically controls the color and brightness displayed on the smart tablet to achieve lower LOD and wider detection ranges. We constructed PCCSM for 24 h, 48 h, and 72 h , and performed colorimetric experiments using both PCDSP and a commercial plate reader (CPR). The results showed that the PCDSP had a lower LOD than that of CPR. Moreover, PCDSP even exhibited a lower LOD for 24 h PCCSM testing compared to CPR for 48 h PCCSM testing, effectively shortening the drug evaluation process. Additionally, the PCDSP offers higher portability and efficiency compared with CPR, making it a promising platform for efficient pancreatic cancer drug screening.

A cardiomyocyte-based biosensing platform for dynamic and quantitative investigation of excessive autophagy.

Autophagy is an important physiological phenomenon in eukaryotes that helps maintain the cellular homeostasis. Autophagy is involved in the development of various cardiovascular diseases, affecting the maintenance of cardiac function and disease prognosis. Physiological levels of autophagy serve as a defense mechanism for cardiomyocytes against environmental stimuli, but an overabundance of autophagy may contribute to the development of cardiovascular diseases. However, conventional biological methods are difficult to monitor the autophagy process in a dynamic and chronic manner. Here, we developed a cardiomyocyte-based biosensing platform that records electrophysiological evolutions in action potentials to reflect the degree of autophagy. Different concentrations of rapamycin-mediated autophagy were administrated in the culture environment to simulate the autophagy model. Moreover, the 3-methyladenine (3-MA)-mediated autophagy inhibition was also investigated the protection on the autophagy. The recorded action potentials can precisely reflect different degrees of autophagy. Our study confirms the possibility of visualizing and characterizing the process of cardiomyocyte autophagy using cardiomyocyte-based biosensing platform, allowing to monitor the whole autophagy process in a non-invasive, real-time, and continuous way. We believe it will pave a promising avenue to precisely study the autophagy-related cardiovascular diseases.

Micronano Synergetic Three-Dimensional Bioelectronics: A Revolutionary Breakthrough Platform for Cardiac Electrophysiology.

Cardiovascular diseases (CVDs) are the leading cause of mortality and therefore pose a significant threat to human health. Cardiac electrophysiology plays a crucial role in the investigation and treatment of CVDs, including arrhythmia. The long-term and accurate detection of electrophysiological activity in cardiomyocytes is essential for advancing cardiology and pharmacology. Regarding the electrophysiological study of cardiac cells, many micronano bioelectric devices and systems have been developed. Such bioelectronic devices possess unique geometric structures of electrodes that enhance quality of electrophysiological signal recording. Though planar multielectrode/multitransistors are widely used for simultaneous multichannel measurement of cell electrophysiological signals, their use for extracellular electrophysiological recording exhibits low signal strength and quality. However, the integration of three-dimensional (3D) multielectrode/multitransistor arrays that use advanced penetration strategies can achieve high-quality intracellular signal recording. This review provides an overview of the manufacturing, geometric structure, and penetration paradigms of 3D micronano devices, as well as their applications for precise drug screening and biomimetic disease modeling. Furthermore, this review also summarizes the current challenges and outlines future directions for the preparation and application of micronano bioelectronic devices, with an aim to promote the development of intracellular electrophysiological platforms and thereby meet the demands of emerging clinical applications.

Assessing the greenification potential of cyclodextrin-based molecularly imprinted polymers for pesticides detection.

Cyclodextrins, with their unparalleled attributes of eco-friendliness, natural abundance, versatile utility, and facile functionalization, make a paramount contribution to the field of molecular imprinting. Leveraging the unique properties of cyclodextrins in molecularly imprinted polymers synthesis has revolutionized the performance of molecularly imprinted polymers, resulting in enhanced adsorption selectivity, capacity, and rapid extraction of pesticides, while also circumventing conventional limitations. As the concern for food quality and safety continues to grow, the need for standard analytical methods to detect pesticides in food and environmental samples has become paramount. Cyclodextrins, being non-toxic and biodegradable, present an attractive option for greener reagents in imprinting polymers that can also ensure environmental safety post-application. This review provides a comprehensive summary of the significance of cyclodextrins in molecular imprinting for pesticide detection in food and environmental samples. The recent advancements in the synthesis and application of molecularly imprinted polymers using cyclodextrins have been critically analyzed. Furthermore, the current limitations have been meticulously examined, and potential opportunities for greenification with cyclodextrin applications in this field have been discussed. By harnessing the advantages of cyclodextrins in molecular imprinting, it is possible to develop highly selective and efficient methods for detecting pesticides in food and environmental samples while also addressing the challenges of sustainability and environmental impact.

Mimicking the Biological Sense of Taste In Vitro Using a Taste Organoids-on-a-Chip System.

Thanks to the gustatory system, humans can experience the flavors in foods and drinks while avoiding the intake of some harmful substances. Although great advances in the fields of biotechnology, microfluidics, and nanotechnologies have been made in recent years, this astonishing recognition system can hardly be replaced by any artificial sensors designed so far. Here, taste organoids are coupled with an extracellular potential sensor array to form a novel bioelectronic organoid and developed a taste organoids-on-a-chip system (TOS) for highly mimicking the biological sense of taste ex vivo with high stability and repeatability. The taste organoids maintain key taste receptors expression after the third passage and high cell viability during 7 days of on-chip culture. Most importantly, the TOS not only distinguishs sour, sweet, bitter, and salt stimuli with great specificity, but also recognizes varying concentrations of the stimuli through an analytical method based on the extraction of signal features and principal component analysis. It is hoped that this bioelectronic tongue can facilitate studies in food quality controls, disease modelling, and drug screening.

Biomimetic integrated gustatory and olfactory sensing array based on HL-1 cardiomyocyte facilitating drug screening for tachycardia treatment.

The ectopic co-expression of taste and olfactory receptors in cardiomyocytes provides not only possibilities for the construction of biomimetic gustatory and olfactory sensors but also promising novel therapeutic targets for tachycardia treatment. Here, bitter taste and olfactory receptors endogenously expressed in HL-1 cells were verified by RT-PCR and immunofluorescence staining. Then HL-1 cardiomyocyte-based integrated gustatory and olfactory sensing array coupling with the microelectrode array (MEA) was first constructed for drugs screening and evaluation for tachycardia treatment. The MEA sensor detected the extracellular field potentials and reflected the systolic-diastolic properties of cardiomyocytes in real time in a label-free and non-invasive way. The in vitro tachycardia model was constructed using isoproterenol as the stimulator. The proposed sensing array facilitated potential drug screening for tachycardia treatment, such as salicin, artemisinin, xanthotoxin, and azelaic acid which all activated specific receptors on HL-1 cells. IC50 values for four potential drugs were calculated to be 0.0036 µM, 309.8 µM, 14.68 µM, and 0.102 µM, respectively. Visualization analysis with heatmaps and PCA cluster showed that different taste and odorous drugs could be easily distinguished. The mean inter-class Euclidean distance between different bitter drugs was 1.681, which was smaller than the distance between bitter and odorous drugs of 2.764. And the inter-class distance was significantly higher than the mean intra-class Euclidean distance of 1.172. In summary, this study not only indicates a new path for constructing novel integrated gustatory and olfactory sensors but also provides a powerful tool for the quantitative evaluation of potential drugs for tachycardia treatment.

Three-Dimensional Cardiomyocyte-Nanobiosensing System for Specific Recognition of Drug Subgroups.

Abnormal cardiac electrophysiological activities significantly contribute to the incidence of cardiovascular diseases. Therefore, it is crucial to recognize effective drugs, which require an accurate, stable, and sensitive platform. Although conventional extracellular recordings offer a non-invasive and label-free manner to monitor the electrophysiological state of cardiomyocytes, the misrepresented and low-quality extracellular action potentials are difficult to provide accurate and high-content information for drug screening. This study presents the development of a three-dimensional cardiomyocyte-nanobiosensing system that can specifically recognize drug subgroups. The nanopillar-based electrode is manufactured by template synthesis and standard microfabrication technology on a porous polyethylene terephthalate membrane. Based on the cardiomyocyte-nanopillar interface, high-quality intracellular action potentials can be recorded by the minimally invasive electroporation. We validate the performance of a cardiomyocyte-nanopillar-based intracellular electrophysiological biosensing platform by two subclasses of sodium channel blockers, quinidine and lidocaine. The recorded intracellular action potentials accurately reveal the subtle differences between these drugs. Our study indicates that high-content intracellular recordings utilizing nanopillar-based biosensing can provide a promising platform for the electrophysiological and pharmacological investigation of cardiovascular diseases.

Self-Illuminating NIR-II Chemiluminescence Nanosensor for In Vivo Tracking H2 O2 Fluctuation.

Chemiluminescence (CL) imaging, as an excitation-free technique, exhibits a markedly improved signal-to-noise ratio (SNR) owing to the absence of an excitation light source and autofluorescence interference. However, conventional chemiluminescence imaging generally focuses on the visible and first near-infrared (NIR-I) regions, which hinders high-performance biological imaging due to strong tissue scattering and absorption. To address the issue, self-luminescent NIR-II CL nanoprobes with a second near-infrared (NIR-II) luminescence in the presence of hydrogen peroxide are rationally designed. A cascade energy transfer, including chemiluminescence resonance energy transfer (CRET) from the chemiluminescent substrate to NIR-I organic molecules and Förster resonance energy transfer (FRET) from NIR-I organic molecules to NIR-II organic molecules, occurs in the nanoprobes, contributing to NIR-II light with great efficiency and good tissue penetration depth. Based on excellent selectivity, high sensitivity to hydrogen peroxide, and long-lasting luminescence performance, the NIR-II CL nanoprobes are applied to detect inflammation in mice, showing a 7.4-fold enhancement in SNR compared with that of fluorescence.

Fabricating Tissues In Situ with the Controlled Cellular Alignments.

Tissue engineering techniques have enabled to replicate the geometrical architecture of native tissues but usually fail to reproduce their exact cellular arrangements during the fabricating process, while it is critical for manufacturing physiologically relevant tissues. To address this problem, a "sewing-like" method of controlling cellular alignment during the fabricating process is reported here. By integrating the stretching step into the fabricating process, a static mechanical environment is created which, in turn, regulates the subsequent cellular alignment, elongation, and differentiation in the generated tissues. With this method, patterned cellular constructs can be fabricated with controlled cellular alignment. Moreover, this method shows a potent capability to fabricate physiologically relevant skeletal muscle constructs in vitro by mechanically inducing myoblast fusion and maturation. As a potential clinical application, aligned myofibers are directly fabricated onto injured muscles in vivo, which repair the damaged tissues effectively. This study shows that the "sewing-like" method can produce engineered tissues with precise control of cellular arrangements and more clinically viable functionalities.

Neuronal network-based biomimetic chip for long-term detection of olfactory dysfunction model in early-stage Alzheimer's disease.

Olfactory dysfunction is an early symptom of neurodegenerative disease. Amyloid-beta oligomers (AßOs), the pathologic protein of Alzheimer's disease (AD), have been confirmed to be firstly deposited in olfactory bulb (OB), causing smell to malfunction. However, the detailed mechanisms underlying pathogenic nature of AßOs-induced olfactory neuronal degeneration in AD are not completely realized. Here, an early-stage olfactory dysfunction pathological model of AD in vitro based on biomimetic OB neuronal network chip was established for dynamic multi-site detection of neuronal electrical activity and network connection. We found both spike firing and correlation of overall neuronal network change regularly displayed gradually active state and then rapidly decay state after AßOs induction. Moreover, MK-801 and memantine were administrated at early-stage to detect alteration of OB neurons simulating nasal administration for AD treatment, which showed an almost recovery through the intermittent firing pattern. Together, this neuronal network-on-chip has revealed synaptic impairment and network neurodegeneration of olfactory dysfunction in AD, providing potential mechanisms information for early-stage progressive olfactory amyloidogenic pathology.

Hybrid Integrated Cardiomyocyte Biosensors for Bitter Detection and Cardiotoxicity Assessment.

Among basic taste sensations, bitter taste is vital to the survival of mammals due to its indispensable role in toxin prediction or identification, so the identification of bitter compounds is of great value in the pharmaceutical and food industry. Recently, bitter taste receptor (T2Rs)-based biosensors have been developed for specific bitter detection. However, the taste biosensors based on taste cells/tissues suffer from simple function, low sensitivity, low content, and limited parameters. Here, to establish a high-content, highly sensitive, and multifunctional taste biosensor, we developed a multifunctional hybrid integrated cardiomyocyte biosensor (HICB) for bitter detection. Due to the expression of bitter taste receptors in cardiomyocytes, the HICB can recognize the specific bitter agonists by synchronously recording the extracellular field potential (EFP) and mechanical beating (MB) signals from the cultured cardiomyocytes in vitro. Multiple feature parameters were defined and extracted from the electromechanical signals of cardiomyocytes to analyze the specific responses to four typical bitter compounds. The radar map, heat map, and principal component analysis (PCA) were used to visualize and classify the specific responses. Moreover, bitter-induced cardiotoxicity also was chronically evaluated, and these bitter compounds presented an inhibition effect on the electrophysiological and contractile activities of cardiomyocytes. This high-content HICB offers an alternative platform for both bitter detection and cardiotoxicity assessment, showing promising applications in the fields of taste detection and toxicity screening.

Biomimetic in vitro respiratory system using smooth muscle cells on ECIS chips for anti-asthma TCMs screening.

Airway smooth muscle (ASM) contraction is a major pathophysiological characteristic of asthma. Although ß2-adrenoceptor (ß2-AR) agonists are currently used as bronchodilators, they cause rapid effect and long-term agonist-induced desensitization. Thus, it is necessary to search for more effective and safer relaxant agents for ASM cells. In this work, bitter taste receptors (TAS2Rs) were demonstrated to be expressed in primary mouse ASM cells endogenously, and they were considered as new drug targets for asthma treatment. Traditional Chinese medicines (TCMs) contained a wide range of TAS2R agonists and some of them had the efficacy of relieving cough and asthma with less toxic side effects. Then the electronic cell-substrate impedance sensor (ECIS) was used for the first time to establish a method to detect the contraction/relaxation effects of ASM cells. Therefore, we introduced a biomimetic in vitro respiratory system using ASM cells on ECIS chips to screen for potential TCMs against asthma. Quinine, nobiletin, and picfeltarraenin IA screened in this study could effectively inhibit the ASM contraction in a concentration-dependent manner, showing potential value as novel anti-asthma drugs. Furthermore, the effective screening of anti-asthma drugs was realized based on 3D ASM cell arrays and gel imaging system. Consistent results were found and the reliability of the biomimetic in vitro respiratory system for the screening of TCMs against asthma was further verified. The biomimetic system designed in this study has the advantages of operation simplicity, high throughput, non-invasive, real-time, and high sensitivity, and therefore provides a promising drug screening platform for asthma disease.