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The desire for exploration of cellular functional mechanisms has substantially increased the rapid development of artificial cells. However, the construction of synthetic cells with high organizational complexity remains challenging due to the lack of facile approaches ensuring dynamic multi-compartments of cytoplasm and stability of membranes in protocells. Herein, a stable coacervate-in-Pickering emulsion protocell model comprising a membraneless coacervate phase formed by poly-l -lysine (PLys) and adenosine triphosphate (ATP) encapsulated in Pickering emulsion is put forward only through simple one-step emulsification. The dynamic distribution of intracellular components (coacervates in this protocell model) can be manipulated by changes in temperature or pH. This coacervate-in-Pickering emulsion protocell system exhibits repeatable cycle stability in response to external stimuli (at least 24 cycles for temperature and 3 cycles for pH). By encapsulating antagonistic enzymes into coacervates, glucose oxidase (GOx) and urease as an example, the control of local enzyme concentration is achieved by introducing glucose and urea to adjust the pH value in Pickering emulsion droplets. This hybrid protocell model with programmatically dynamic microcompartmentation and sufficient stability is expected to be further studied and applied in cellular biology, facilitating the development of lifelike systems with potential in practical applications.  相似文献   

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As a model protocell, the membrane‐free coacervate microdroplet is widely utilized in functional studies to provide insights into the physicochemical properties of the cell and to engineer cytomimetic soft technologies; however, the lack of a discrete membrane contributes to its instability and limits further application. Herein, a strategy is developed to fabricate a hybrid protocell based on the self‐assembly of a proteinaceous membrane at the surface of coacervate microdroplets driven by a combination of electrostatic adhesion and steric/hydrophilic surface buoyancy. The semipermeable proteinaceous membrane can enhance coacervate stability obviously without compromising sequestration behavior. Significantly, such hybrid protocells demonstrate spatial organization whereby various functional enzymes can be located in discrete regions, which facilitates an on/off modulation for a cascade enzymatic reaction along with enhanced chemical communication between subpopulations.  相似文献   

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Neuroblastoma cells can acquire resistance mechanisms that make them invulnerable to chemotherapeutic agents. The use of nanoparticles as drug carriers provides the possibility to deliver several drugs simultaneously to specific tumoral cell populations, improving their therapeutic outcome. Herein, the development of a multifunctional nanoplatform based on the assembly of protocells (PC) and polymeric nanocapsules (PNC) is reported. PC provides the ability to transport and release cytotoxic drugs while PNC offers the capacity to transport enzymes to the tumoral tissues preserving their catalytic activity. Doxorubicin (Dox) and Glucose Oxidase (Gox) are housed within PC and PNC, respectively. The external surface of these nanoassemblies is decorated with synthetic targeting moieties, providing selectivity to neuroblastoma cells. Thus, the nanoplatform is endowed with the ability to generate multiple insults within neuroblastoma cells as cytotoxic drug release, glucose starvation, and oxidative damage. This nanoplatform exhibits significantly higher cytotoxic activity in comparison with only drug-loaded protocells or empty protocells decorated with glucose oxidase nanocapsules, which points out the existence of a potent synergic effect between the action of both therapeutic agents: Dox and Gox. This strategy can be adapted to the production of multifunctional nanoassemblies, improving the arsenal against different types of tumors.  相似文献   

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Multicellular organisms demonstrate a hierarchical organization where multiple cells collectively form tissues, thereby enabling higher-order cooperative functionalities beyond the capabilities of individual cells. Drawing inspiration from this biological organization, assemblies of multiple protocells are developed to create novel functional materials with emergent higher-order cooperative functionalities. This paper presents new artificial tissues derived from multiple vesicles, which serve as protocellular models. These tissues are formed and manipulated through non-covalent interactions triggered by a salt bridge. Exhibiting pH-sensitive reversible formation and destruction under neutral conditions, these artificial vesicle tissues demonstrate three distinct higher-order cooperative functionalities: transportation of large cargoes, photo-induced contractions, and enhanced survivability against external threats. The rapid assembly and disassembly of these artificial tissues in response to pH variations enable controlled mechanical task performance. Additionally, the self-healing property of these artificial tissues indicates robustness against external mechanical damage. The research suggests that these vesicles can detect specific pH environments and spontaneously assemble into artificial tissues with advanced functionalities. This leads to the possibility of developing intelligent materials with high environmental specificity, particularly for applications in soft robotics.  相似文献   

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Self‐reproduction in compartmentalized chemical ensembles is a central issue for the development of new materials and processes capable of autonomous behavior, self‐amplification and artificial evolution. Current approaches to synthetic cellularity focus primarily on self‐assembled soft matter systems such as membrane‐bounded lipid vesicles, which have sufficient structural plasticity to undergo growth and division. Steps towards inorganic protocells are being advanced, but self‐reproduction in these more structurally robust micro‐compartments has not been demonstrated. Here, a primitive form of growth and division involving inorganic colloidosomes (Pickering emulsions), comprising aqueous micro‐droplets enclosed by an ultrathin membrane of silica nanoparticles, is shown. Growth of the colloidosomes is induced by organosilane‐mediated methanol formation, and results in a localized rupture of the inorganic membrane followed by outgrowth and separation of a second‐generation protocell, which is stabilized by de novo nanoparticle assembly. These observations provide a first step towards synthetic cell‐like inorganic materials capable of chemically induced self‐reproduction.  相似文献   

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Controlled membrane fusion of proteinosome‐based protocells is achieved via a hydrogel‐mediated process involving dynamic covalent binding, self‐healing, and membrane reconfiguration at the contact interface. The rate of proteinosome fusion is dependent on dynamic Schiff base covalent interchange, and is accelerated in the presence of encapsulated glucose oxidase and glucose, or inhibited with cinnamyl aldehyde due to enzyme‐mediated decreases in pH or competitive covalent binding, respectively. The coordinated fusion of the proteinosomes leads to the concomitant transportation and redistribution of entrapped payloads such as DNA and dextran. Silica colloids with amino‐functionalized surfaces undergo partial fusion with the proteinosomes via a similar dynamic hydrogel‐mediated mechanism. Overall, the strategy provides opportunities for the development of interacting colloidal objects, control of collective behavior in soft matter microcompartmentalized systems, and increased complexity in synthetic protocell communities.  相似文献   

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As we move towards the miniaturization of devices to perform tasks at the nano and microscale, it has become increasingly important to develop new methods for actuation, sensing, and control. Over the past decade, bio‐hybrid methods have been investigated as a promising new approach to overcome the challenges of scaling down robotic and other functional devices. These methods integrate biological cells with artificial components and therefore, can take advantage of the intrinsic actuation and sensing functionalities of biological cells. Here, the recent advancements in bio‐hybrid actuation are reviewed, and the challenges associated with the design, fabrication, and control of bio‐hybrid microsystems are discussed. As a case study, focus is put on the development of bacteria‐driven microswimmers, which has been investigated as a targeted drug delivery carrier. Finally, a future outlook for the development of these systems is provided. The continued integration of biological and artificial components is envisioned to enable the performance of tasks at a smaller and smaller scale in the future, leading to the parallel and distributed operation of functional systems at the microscale.  相似文献   

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Elevated temperatures might have promoted the nucleation, growth, and replication of protocells on the early Earth. Recent reports have shown evidence that moderately high temperatures not only permit protocell assembly at the origin of life, but can have actively supported it. Here, the fast nucleation and growth of vesicular compartments from autonomously formed lipid networks on solid surfaces, induced by a moderate increase in temperature, are shown. Branches of the networks, initially consisting of self‐assembled interconnected nanotubes, rapidly swell into microcompartments which can spontaneously encapsulate RNA fragments. The increase in temperature further causes fusion of adjacent network‐connected compartments, resulting in the redistribution of the RNA. The experimental observations and the mathematical model indicate that the presence of nanotubular interconnections between protocells facilitates the fusion process.  相似文献   

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Eukaryotic cells have inner compartments (organelles), each with distinct properties and functions. One mimic of this architecture, based on biopolymers, is the multicompartment capsule (MCC). Here, MCCs in which the inner compartments are chemically unique and “smart,” i.e., responsive to distinct stimuli in an orthogonal manner are created. Specifically, one compartment alone is induced to degrade when the MCC is contacted with an enzyme while other compartments remain unaffected. Similarly, just one compartment gets degraded upon contact with reactive oxygen species generated from hydrogen peroxide (H2O2). And thirdly, one compartment alone is degraded by an external, physical stimulus, namely, by irradiating the MCC with ultraviolet (UV) light. All these specific responses are achieved without resorting to complicated chemistry to create the compartments: the multivalent cation used to crosslink the biopolymer alginate (Alg) is simply altered. Compartments of Alg crosslinked by Ca2+ are shown to be sensitive to enzymes (alginate lyases) but not to H2O2 or UV, whereas the reverse is the case with Alg/Fe3+ compartments. These results imply the ability to selectively burst open a compartment in an MCC “on-demand” (i.e., as and when needed) and using biologically relevant stimuli. The results are then extended to a sequential degradation, where compartments in an MCC are degraded one after another, leaving behind an empty MCC lumen. Collectively, this work advances the MCC as a platform that not only emulates key features of cellular architecture, but can also begin to capture rudimentary cell-like behaviors.  相似文献   

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Creating artificial enzymes that mimic the complexity and function of natural systems has been a great challenge for the past two decades. In this Progress Report, the focus is on recently discovered “hidden talents” of gold nanomaterials in artificial enzymes, including mimicking of nuclease, esterase, silicatein, glucose oxidase, peroxidase, catalase, and superoxide dismutase. These unexpected enzyme‐like activities can be ascribed to nano‐gold itself or the functional groups present on surrounding monolayer. Along with introducing the mechanisms of the various enzyme‐like activities, the design and development of gold‐based biomimetic catalysts, the search for efficient modulators, and their potential applications in bionics, biosensing, and biomedical sciences are highlighted. Eventually, it is expected that the rapidly growing interest in gold‐based nanozymes will certainly fuel the excitement and stimulate research in this highly active field.  相似文献   

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A domain decomposition approach for the solution of the coupled electro‐mechanical problem in dynamics is proposed. The finite element analysis of a coupled electro‐mechanical system is frequently found, for example, in the modelling and design of microsystems and may lead to a burdensome nonlinear problem solution, particularly in the dynamic case. Two versions of the algorithm are proposed: the first one, called single‐level decomposition, exploits the natural partition of the analysis domain given by the two physics to be solved; the second one, called two‐level decomposition, adds a further subdivision of each physics into subdomains. The multilevel domain decomposition strategy here proposed is shown to accurately predict the response of microsystems subjected to electro‐mechanical coupling and to allow for a significant reduction in the computational burden. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

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桂宇晖  刘婧  刘军  宋刚 《包装工程》2020,41(6):26-31
目的在人工智能高速发展,自然语言处理技术得到显著提高的背景下,探讨语音识别技术对智慧工厂类系统中交互设计范式的影响。方法从形式层面、内容层面、操作层面对语音交互的要素进行剖析,结合公理化设计理论,得出语音交互研究框架,基于\"中国石油智慧油库设备管理系统\"的相关研发设计的实际验证,通过对四十名熟练操作人员的GUI与VUI输入交互方式进行对比测试分析,评估语音识别技术在智慧工厂交互设计中的应用可行性。结论研究结果表明,选择多通道交互技术并行、随场景转换交互方式、感官语义的有效引导和构建虚拟人物角色的语音交互设计原则,能够降低用户的学习成本和使用智慧工厂系统的操作时间,提升操作效率,为语音交互在智慧工厂中的应用提供参考依据。  相似文献   

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目的研究情感交互系统在设计层面上的重要新兴趋势,探讨以人为本的情感交互设计方案及在其研究领域中的人工智能技术的实际应用。方法在情感交互设计中,机器需要实时捕捉用户的关键信息,识别用户的情感状态,利用多种线索最终决定合适的用户模型。首先通过分析人工智能技术在人类情感识别上的分类优势,讨论如何利用面部表情、肢体动作、语言、心跳、呼吸等多模态用户特征,使机器更加准确地识别人类情感;其次通过分析经典的情绪状态的数学模型以及情绪表达与交互优化等关键要素,针对用户的情感作出自然、合理、友好的反应;最后探讨情感交互系统设计和模块化构建的可行性。结论提出一种利用人工智能技术的情感交互系统的模块化设计方案。  相似文献   

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人工智能对交互设计的影响研究   总被引:9,自引:9,他引:0  
覃京燕 《包装工程》2017,38(20):27-31
目的人工智能对交互的感知方式及认知逻辑影响较大,交互设计的方法、交互设计的流程、认知心智模型、交互技术及交互界面的表现方式在人工智能的影响下,已经发生颠覆式改变。交互设计面对新的技术变化,需要从技术哲学与创新思维及设计技法方面进行新的探索。方法通过文献综述人工智能的发展历史,对比研究人类智能与人工智能的差异关系,结合无人驾驶车产品服务系统的交互设计等案例分析,提出混合智能的概念,辨析人工智能与人类智慧混合作用于交互设计所带来的变化。结论混合智能对交互设计方法流程、设计细则、设计评判都会有新的特征表现,通过人工智能产品交互设计,印证人工智能对交互设计带来的深刻影响。  相似文献   

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An ultrasound‐based platform is established to prepare homogenous arrays of giant unilamellar vesicles (GUVs) or red blood cell (RBCs), or hybrid assemblies of GUV/RBCs. Due to different responses to the modulation of the acoustic standing wave pressure field between the GUVs and RBCs, various types of protocell/natural cell hybrid assemblies are prepared with the ability to undergo reversible dynamic reconfigurations from vertical to horizontal alignments, or from 1D to 2D arrangements. A two‐step enzymatic cascade reaction between transmitter glucose oxidase‐containing GUVs and peroxidase‐active receiver RBCs is used to implement chemical signal transduction in the different hybrid micro‐arrays. Taken together, the obtained results suggest that the ultrasound‐based micro‐array technology can be used as an alternative platform to explore chemical communication pathways between protocells and natural cells, providing new opportunities for bottom‐up synthetic biology.  相似文献   

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目的指出\"支持人在环路混合智能的交互设计\"这一类设计问题,研究人在环路混合智能系统中交互设计的问题,为相关设计、技术与应用研究提供索引和参考。方法从人在环路混合智能的概念和架构出发,引出人在环路混合智能的交互设计;基于对相关文献的整理,总结常见界面构成和交互方式;总结整理人在环路混合智能的生命周期。结论指明了人在环路混合智能是需要用户交互的智能模型,介绍了由用户、人工智能算法、用户接口构成的系统架构;总结了针对不同数据类型的现有工作可能的交互方式;分析了人在环路混合智能完整生命周期中的设计挑战,根据现有文献提取关键界面构成,提出了人在环路混合智能系统的设计建议;提出了从智能系统、用户、设计师三方面建立设计方法论,完善设计工具,更有效地支持和推动人在环路混合智能系统的应用的建议。  相似文献   

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