Bio-Design and Manufacturing最新文献

Polycaprolactone (PCL) scaffolds that are produced through additive manufacturing are one of the most researched bone tissue engineering structures in the field. Due to the intrinsic limitations of PCL, carbon nanomaterials are often investigated to reinforce the PCL scaffolds. Despite several studies that have been conducted on carbon nanomaterials, such as graphene (G) and graphene oxide (GO), certain challenges remain in terms of the precise design of the biological and nonbiological properties of the scaffolds. This paper addresses this limitation by investigating both the nonbiological (element composition, surface, degradation, and thermal and mechanical properties) and biological characteristics of carbon nanomaterial-reinforced PCL scaffolds for bone tissue engineering applications. Results showed that the incorporation of G and GO increased surface properties (reduced modulus and wettability), material crystallinity, crystallization temperature, and degradation rate. However, the variations in compressive modulus, strength, surface hardness, and cell metabolic activity strongly depended on the type of reinforcement. Finally, a series of phenomenological models were developed based on experimental results to describe the variations of scaffold’s weight, fiber diameter, porosity, and mechanical properties as functions of degradation time and carbon nanomaterial concentrations. The results presented in this paper enable the design of three-dimensional (3D) bone scaffolds with tuned properties by adjusting the type and concentration of different functional fillers.

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The plausibility of human exposure to particulate matter (PM) has witnessed an increase within the last several years. PM of different sizes has been discovered in the atmosphere given the role of dust transport in weather and climate composition. As a regulator, the lung epithelium orchestrates the innate response to local damage. Herein, we developed a lung epithelium-on-a-chip platform consisting of easily moldable polydimethylsiloxane layers along with a thin, flexible, and transparent ionic liquid-based poly(hydroxyethyl) methacrylate gel membrane. The epithelium was formed through the culture of human lung epithelial cells (Calu-3) on this membrane. The mechanical stress at the air–liquid interface during inhalation/exhalation was recapitulated using an Arduino-based servo motor system, which applied a uniaxial tensile strength from the two sides of the chip with 10% strain and a frequency of 0.2 Hz. Subsequently, the administration of silica nanoparticles (PM0.5) with an average size of 463 nm to the on-chip platform under static, dynamic, and dynamic + mechanical stress (DMS) conditions demonstrated the effect of environmental pollutants on lung epithelium. The viability and release of lactate dehydrogenase were determined along with proinflammatory response through the quantification of tumor necrosis factor-α, which indicated alterations in the epithelium.

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The combined use of guided tissue/bone regeneration (GTR/GBR) membranes and bone filling grafts represents a classical therapy for guiding the regeneration and functional reconstruction of oral soft and hard tissues. Nevertheless, due to its displacement and poor mechanical support, bone meal is not suitable for implantation in the case of insufficient cortical bone support and large dimensional defects. The combination of GTR/GBR membrane with a three-dimensional (3D) porous scaffold may offer a resolution for the repair and functional reconstruction of large soft and hard tissue defects. In this study, a novel integrated gradient biodegradable porous scaffold was prepared by bonding a poly(lactic-co-glycolic acid) (PLGA)/fish collagen (FC) electrospun membrane (PFC) to a 3D-printed PLGA/nano-hydroxyapatite (HA) (PHA) scaffold. The consistency of the composition (PLGA) ensured strong interfacial bonding between the upper fibrous membrane and the lower 3D scaffold. In vitro cell experiments showed that the PFC membrane (upper layer) effectively prevented the unwanted migration of L929 cells. Further in vivo investigations with an oral soft and hard tissue defect model in beagles revealed that the integrated scaffold effectively guided the regeneration of defective oral tissues. These results suggest that the designed integrated scaffold has great potential for guiding the regeneration and reconstruction of large oral soft and hard tissues.

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导电聚合物涂层以其优异的电化学性能，在神经电极领域受到广泛关注。其中，聚（3,4-乙烯二氧噻吩）：聚（苯乙烯磺酸）（PEDOT:PSS）是一个典型的代表。然而，这些导电聚合物涂层对铂铱等常用电极材料的附着力弱，严重制约了其实际应用。为了克服这一挑战，本研究探索了利用飞秒激光制备层级铂铱基底来增强PEDOT:PSS涂层的粘附稳定性。通过重复循环伏安测试和加速老化测试，评价光滑铂铱和层级铂铱基底上滴铸及电化学沉积两种方式制备的PEDOT:PSS涂层的稳定性。结果表明，经过2000次重复循环伏安扫描或在60 °C下老化五周后，层级铂铱基底表面的涂层形貌和电化学性能保持相对稳定；相比之下，光滑铂铱基底表面的PEDOT:PSS涂层出现了分层、开裂，并表现出电荷存储能力的降低和阻抗的升高。综上，采用飞秒激光制备层级结构可以显著增强铂铱神经电极表面PEDOT:PSS涂层的稳定性，这为提高电极电化学性能、开发多模态神经电极提供了巨大的潜力。

Point-of-care testing (POCT) is the practice of diagnosing and monitoring diseases where the patient is located, as opposed to traditional treatment conducted solely in a medical laboratory or other clinical setting. POCT has been less common in the recent past due to a lack of portable medical devices capable of facilitating effective medical testing. However, recent growth has occurred in this field due to advances in diagnostic technologies, device miniaturization, and progress in wearable electronics. Among these developments, electrochemical sensors have attracted interest in the POCT field due to their high sensitivity, compact size, and affordability. They are used in various applications, from disease diagnosis to health status monitoring. In this paper we explore recent advancements in electrochemical sensors, the methods of fabricating them, and the various types of sensing mechanisms that can be used. Furthermore, we delve into methods for immobilizing specific biorecognition elements, including enzymes, antibodies, and aptamers, onto electrode surfaces and how these sensors are used in real-world POCT settings.

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Recently, the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication methods. Lasers have long been used to develop original solutions to such challenging technological problems due to their remote, sterile, rapid, and site-selective processing of materials. In this review, recent developments in relevant laser processes are summarized under two separate categories. First, transformative approaches, such as for laser-induced graphene, are introduced. In addition to design optimization and the alteration of a native substrate, the latest advances under a transformative approach now enable more complex material compositions and multilayer device configurations through the simultaneous transformation of heterogeneous precursors, or the sequential addition of functional layers coupled with other electronic elements. In addition, the more conventional laser techniques, such as ablation, sintering, and synthesis, can still be used to enhance the functionality of an entire system through the expansion of applicable materials and the adoption of new mechanisms. Later, various wearable device components developed through the corresponding laser processes are discussed, with an emphasis on chemical/physical sensors and energy devices. In addition, special attention is given to applications that use multiple laser sources or processes, which lay the foundation for the all-laser fabrication of wearable devices.

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Wearable biosensors have received great interest as patient-friendly diagnostic technologies because of their high flexibility and conformability. The growing research and utilization of novel materials in designing wearable biosensors have accelerated the development of point-of-care sensing platforms and implantable biomedical devices in human health care. Among numerous potential materials, conjugated polymers (CPs) are emerging as ideal choices for constructing high-performance wearable biosensors because of their outstanding conductive and mechanical properties. Recently, CPs have been extensively incorporated into various wearable biosensors to monitor a range of target biomolecules. However, fabricating highly reliable CP-based wearable biosensors for practical applications remains a significant challenge, necessitating novel developmental strategies for enhancing the viability of such biosensors. Accordingly, this review aims to provide consolidated scientific evidence by summarizing and evaluating recent studies focused on designing and fabricating CP-based wearable biosensors, thereby facilitating future research. Emphasizing the superior properties and benefits of CPs, this review aims to clarify their potential applicability within this field. Furthermore, the fundamentals and main components of CP-based wearable biosensors and their sensing mechanisms are discussed in detail. The recent advancements in CP nanostructures and hybridizations for improved sensing performance, along with recent innovations in next-generation wearable biosensors are highlighted. CP-based wearable biosensors have been—and will continue to be—an ideal platform for developing effective and user-friendly diagnostic technologies for human health monitoring.

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在辅助生殖过程中，选择活力强且功能完好的精子是确保胚胎发育成功的关键步骤。传统的精子样本处理方法，如离心和洗涤，可能引入机械损伤和氧化应激，影响精子质量。尽管微流控技术通过模拟精子自然游动方式以减少这些不利影响，但现有方法尚未经过临床级别的全面验证。受自然环境下输卵管中精子选择机制以及精子对温度梯度的内在响应特性的启发，我们设计并制造了一种微流控装置，该装置在精子分选通道内形成可控的温度梯度。我们系统地研究了人类精子在不同温度条件下的响应，并全面评估了45份人类精子样本通过趋温性选择的效果。研究结果表明，在35~36.5 ℃的温度范围内，与非趋温性选择相比，通过趋温性选择的精子展现出更高的活率（（85.25±6.28）% vs.（60.72±1.37）%；P=0.0484），更高的正常形态率（（16.42±1.43）% vs.（12.55±0.88）%；P<0.0001），以及更低的DNA碎片率（（7.44±0.79）% vs.（10.36±0.72）%；P=0.0485）。此外，精子趋温性表现出物种特异性，小鼠精子在36~37.5 ℃的温度范围内活力最高。体外受精实验进一步证实，利用趋温性选择的精子显著提高了受精率，并改善了从受精卵到囊胚的胚胎发育过程。本研究提出并验证了一种基于微流控技术的趋温性精子选择方法。该方法不仅能够有效选择高活力和功能完好的精子，而且能够降低传统处理方法可能带来的不利影响。这一创新方法有望在未来转化为临床实践，特别是在少精子症和弱精子症患者的体外受精治疗中，以提高受精率和胚胎发育的成功率。