Membranous Nanogenerators for in vivo Bio-mechanical Energy Harvesting

 描述：只有通过开发能够在体内从植入物周围获取能量的新型电源，才有可能实现提供持续、实时检测、监测和各种其他重要健康功能的自供电植入型生物医学设备。人体内的各种能源，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能量。然而，将体内能量采集设备开发成有用的电力仍处于起步阶段。在这个项目中，我们建议探索创新的纳米技术来开发超薄、轻质、可拉伸和生物相容的模数可调的压电聚合物膜，可以高效和谨慎地将人体内存在的纳米/微米级的机械能转化为电能，从而实现植入式生物医学设备的自给自足电源。该项目建立在Pi(Wang)S最近开发的柔性纳米发电机(NG)的基础上，NG是一种利用聚合物压电纳米材料将机械能有效转化为电能的新方法。Co-I(Cai)在小动物的活体成像研究和外科手术方面拥有10年的经验。CoI Kohmoto博士专门从事临床心脏外科和心脏生理学的所有领域，并将监督和执行拟议工作中所需的先进外科程序。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、研究和优化拟议的体外和体内可植入NGS。在具体目标1中，我们将以具有海绵状内部介孔的聚偏氟乙烯(PVDF)为原料制备柔性膜。通过控制孔的尺寸和密度来控制膜的机械和压电性能，从而最大限度地提高机械能的吸收和转换。在特定的目标2中，我们将在模拟的活体条件下研究和优化与形态相关的获取生物机械能的能力。将对封装材料和电路进行研究，以最大限度地减少NGS的杂散电流。 在具体目标3中，我们将通过瘢痕组织生长、缝合和针孔辅助附着等一系列策略来提高NG膜在肌肉/组织表面的长期稳定性。将对静态和动态附着稳定性以及潜在的炎症和生物污垢问题进行调查和优化。在具体目标4中，将使用小鼠或大鼠在活体中研究从肢体运动、心跳和横隔膜扩张中获取生物机械能量的与形态相关的能力。这项研究将克服制造生物兼容的压电聚合物纳米结构的尚未克服的挑战，并建立一种从人体中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、最大限度地减少保护组件以及解决电池系统的安全问题，为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.