Increasing neurological and cardiovascular diseases are increasingly demanding implantable medical electronic devices, and their performance requirements are increasing. These electronic devices mainly include: intracardiac pressure sensors, cardiac pacemakers, Cardiac defibrillators, deep brain/neural stimulators, etc. Long-term in vivo implantation places high demands on the volume, stability and biocompatibility of implantable medical devices. Existing power supplies for implantable medical electronic devices Mainly rely on commercial rechargeable and non-rechargeable batteries. Such commercial batteries often have problems such as heat generation, capacity reduction and internal denaturation in actual use. Once such power supplies reach the end of their service life, the patient has to undergo a second operation to remove them. In vivo removal, this process will impose a great burden on the patient's psychology and economy. Therefore, it is urgent to develop a new power supply to power the implanted electronic device, and provide a feasible solution to solve the above problems.
Implantable friction nanogenerator (iTENG) is an energy conversion device implantable in the body. It is widely used in society for its unique working mode (triboelectric and electrostatic induction) and effective energy conversion efficiency. iTENG can be used for collection. Different forms of biomechanical energy can be effectively converted into electrical energy. Such biomechanical energy can be derived from heartbeat, respiration, limb movement and pulse beat. A large number of experiments have proved that iTENG converted electrical energy can be successfully used for cardiac pacing, health monitoring. And cell tissue engineering. Recently, in the Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing Institute of Nano-Energy and Systems Research Institute, Wang Zhonglin, researcher Li Zhou and Beijing University of Aeronautics and Astronautics Professor Fan Yubo, Dr. Jiang Wen, PhD student Li Hu and Liu Zhuo et al. developed five different types of natural bioabsorbable friction nanogenerators (BN-TENGs) using five natural sources of degradable materials (cellulose/chitin/silkin/rice/egg). Five kinds of natural materials were tested in combination, and the electric order was arranged to design natural degradable BN-TE for the future. NGs, as well as the structure and material selection of other energy harvesting devices, provide the research basis and data.
The natural bioabsorbable BN-TENGs developed by this work have good biocompatibility, biodegradability and bioabsorbability. In addition, it has high biomechanical energy conversion efficiency, BN-TENGs can be realized in Working properly in vivo and in vitro, and converting biomechanical energy into electrical energy, BN-TENGs can output up to 55V, current up to 0.6μA, and power density up to 21.6mW m-2. By using different packaging methods, the work Controlled degradation of BN-TENGs in vivo and in vitro was achieved.
At the same time, the researchers used BN-TENGs as a voltage source for dysfunctional cardiomyocytes, successfully regulating the rate of beating of cardiomyocytes. When BN-TENGs completed the scheduled task, implanted into SD rats, BN-TENGs It can be degraded and absorbed by SD rats. This work provides new treatments for diseases such as bradycardia and arrhythmia. In addition, the BN-TENGs developed by this work have great potential as power-driven implantable medical electronic devices. After completing its established tasks, it can be degraded and absorbed by the organism to avoid secondary surgery.
The relevant research results are published in the latest issue of Advanced Materials (DOI: 10.1002/adma.201801895) under the topic of Fully Bioabsorbable Natural-Materials-Based Triboelectric Nanogenerators. This work has been approved by the Ministry of Science and Technology. (2016YFA0202702, 2016YFA0202703), National Natural Science Foundation of China (31571006, 81601629, 61501039), Beijing Top Talents (2015000021223ZK21), Beijing Natural Science Foundation (2182091 and 2162017) and the “Top Thousand People” of the Central Organization Department and their innovative team Financial support.
Figure: (a) Five sources of pure natural materials; (b)- (d) BN-TENG structure diagram and friction layer surface structure diagram; (e)-(f) BN-TENG as power source for electrical stimulation of cardiomyocytes
