Membranous Nanogenerators for in vivo Bio-mechanical Energy Harvesting

 产品说明：自供电的植入式生物医学设备提供连续的，实时的传感，监测和各种其他重要的健康功能，只有通过开发新的电源，可以从植入物的周围环境中获取能量，在体内才有可能。人体内的各种能量来源，如肢体关节、呼吸和心跳，都可以为小型生物医学设备提供足够的电力。然而，将体内能量收集装置发展成有用的电力仍处于起步阶段。在这个项目中，我们计划探索创新的纳米技术，开发可调节模量的可伸缩、轻质、可拉伸和生物相容的压电聚合物膜，可以有效地将人体内发现的纳米/微米级机械能转换为电能，从而实现可植入生物医学设备的自给自足的电源。该项目建立在PI（Wang）最近开发的柔性纳米发电机（NG）的基础上-这是一种使用聚合物压电纳米材料将机械能有效转换为电能的新方法。Co-I（Cai）在小动物体内成像研究和外科手术方面拥有超过10年的经验。Kohmoto博士专门从事临床心脏手术和心脏生理学的所有领域，并将监督和执行拟议工作所需的先进外科手术。他们共同组成了一个具有互补专业知识的协同团队，以设计，研究和优化体外和体内的植入式NG。在具体目标1中，我们将从聚偏二氟乙烯（PVDF）制造具有海绵状内部中孔性的柔性膜。将控制孔尺寸和密度以设计膜的机械和压电性质，从而使机械能吸收和转换最大化。在具体目标2中，我们将研究和优化在模拟体内条件下收集生物机械能的形态学相关能力。将研究封装材料和电路，以减少NG的杂散电流。 在特定目标3中，我们将通过一系列策略（如瘢痕组织生长、缝线和针孔辅助附着）提高NG膜在肌肉/组织表面上的长期稳定性。静态和动态粘附稳定性以及潜在的炎症和生物污垢问题将被研究和优化。在具体目标4中，将使用小鼠或大鼠在体内研究从肢体运动、心跳和膈肌扩张中收集生物机械能的形态学相关能力。这项研究将克服制造生物相容性压电聚合物纳米结构的不可逾越的挑战，并建立一种从人体提取有用电能的新能力，同时对器官的正常功能产生最小的影响。该项目的成功将通过减小尺寸、降低能量密度、最小化保护封装以及解决电池系统的安全问题，对当前救生植入式设备的功率组件的进步做出重大贡献。

 DESCRIPTION: Self-powered implantable biomedical devices that provide continuous, real-time sensing, monitoring, and various other vital health functions will only be possible through the development of novel power sources that can harvest energy from the implant's surroundings, in vivo. A variety of energy sources in the human body such as limb articulation, respiration, and heartbeat can provide sufficient power for small biomedical devices. However, the development of in vivo energy harvesting devices into useful electrical power is still in infancy. In this project, we propose to explore innovative nanotechnology to develop ultrathin, lightweight, stretchable and bio-compatible piezoelectric polymer membranes with tunable modulus that can efficiently and discreetly convert the nano-/microscale mechanical energy found in human body to electrical energy, and thereby realize a self-sufficient power supply for implantable biomedical devices. This project builds on the PI (Wang)'s recent development of flexible nanogenerator (NG) - a novel approach for effectively converting mechanical energy into electric energy using polymeric piezoelectric nanomaterials. The Co-I (Cai) has >10 years of experience with in vivo imaging studies and surgical procedures in small animals. The Co-I Dr. Kohmoto specializes in all areas of clinical cardiac surgery and cardiac physiology, and will oversee and perform the advanced surgical procedures needed in the proposed work. Together they form a synergistic team with complementary expertise to design, investigate, and optimize the proposed implantable NGs both ex vivo and in vivo. In Specific Aim 1, we will fabricate flexible membranes from polyvinylidene fluoride (PVDF) with a sponge-like internal mesoporosity. The pore dimension and density will be controlled to engineer the membrane's mechanical and piezoelectric properties, and thus to maximize the mechanical energy absorption and conversion. In Specific Aim 2, we will investigate and optimize the morphology-related capability of harvesting bio-mechanical energy in simulated in vivo conditions. The encapsulation material and electric circuit will be studied to minimize the stray current from NGs. In Specific Aim 3, we will improve the long-term stability of NG membrane on muscle/tissue surfaces via a series of strategies such as scar tissue growth, suture- and pin hole-assisted attachment. The static and dynamic adhesion stability, as well as the as well as potential inflammation and biofouling issues will be investigated and optimized. In Specific Aim 4, the morphology-related capability of harvesting bio-mechanical energy from limb movement, heartbeat, and diaphragm expansion will be studied in vivo using mice or rats. This research will overcome the yet insurmountable challenges of fabricating biocompatible piezoelectric polymer nanostructures and establish a new capability of extracting useful electrical energy from the human body while resulting in minimal impact on the organ's normal functions. The success of this project will make significant contribution to the advancement of the power components of current life-saving implantable devices by reducing the size, lowering the energy density, minimizing the protection package, and resolving safety concerns of the battery systems.