图5.(a)TIF
Schematic diagram of manufacturing. (b)TIF
Optical photographs. (c
) useTIF
Schematic diagram of the temperature sensing mechanism
Li et al. developed a multifunctional sensor based on ionic gels for body temperature monitoring and joint motion detection, which is based on ionic liquids (ILs) and ionic gels of commercial thermoplastic polyurethane (TPU) fibers, prepared by impregnation method. The EMIM+ and TFSI− content in T IF can be adjusted by controlling the heating temperature, as shown in FigTIF at different temperatures was prepared as shown in 5a. As shown in Figure 5b, the obtained TIF retains good flexibility and elasticity, and also maintains the transparency of the TPU fibers. Figure 5c illustrates that when a smart fiber (TIF) is stimulated by temperature, the degree of dissociation and mobility of ion pairs in the ionic gel increases with increasing temperature, which means that at higher temperatures, the ions in the ionic gel are able to move more quickly, changing the conductivity of the material. Figures 5d and e show TIFS prepared at 90 °C at 20 to 40 ◦CThe impedance change and temperature response over the temperature range demonstrate the sensitivity of the sensor to temperature changes, reflecting the sensor's high temperature sensitivity (2.73%°C⁻¹) and sufficient resolution (0.1 °C).
In summary, the ionic gel-based multifunctional sensor proposed in this paper provides a high-sensitivity and high-resolution monitoring method for body temperature monitoring, which is helpful to improve the quality and convenience of personal health monitoring, demonstrating TENGPotential for wide range of applications in personal health management and medical monitoring.
3.2 Implantable Medical Devices
The application of TENG technology in the field of implantable medical devices, especially in cardiac pacemakers and drug delivery systems, shows great potential and innovation.
3.2.1 Cardiac pacemakers
TENG
The application of technology in pacemakers is an area of innovation that aims to provide a self-powered solution for pacemakers. A pacemaker is an implanted medical device used to treat arrhythmias, usually powered by batteries.TENG
Technology is able to convert mechanical energy, such as a beating heart, into electrical energy to provide a continuous source of energy for pacemakers, reducing or eliminating the need to replace batteries.
Figure 6(a-c) The open-circuit voltage, transfer charge, and short-circuit current of the I-TENG driven by a linear motor. (d) Peak power density at different load resistances. (e) I-TENG stability test. (f) Statistical analysis of minimum voltage, maximum voltage and voltage difference. (g) Statistical analysis of the difference between the minimum transfer charge, the maximum transfer charge, and the transfer charge.
In one study, Ouyang et al. developed a symbiotic pacemaker (SPM) that is able to obtain energy from the heart's beating to provide electrical energy to the pacemaker itself. The energy-harvesting part of this pacemaker is an implantable triboelectric nanogenerator (I-TENG), which consists of two triboelectric layers, a support structure, and a shell with two encapsulation layers, which is extremely flexible and biocompatible. Figure 6a-c illustrates the performance of the I-TENG in vitro testing, reflecting the high output performance of the device. Figure 6d illustrates the high power density of the I-TENG. Figure e shows the stability test results of I-TENG after 100 million mechanical stimulation cycles, demonstrating its good durability. Excellent stability and high power output performance in living organisms. Figure f-g illustrates the energy harvesting and electrical properties of I-TENG in vivo, and it can be concluded that the energy produced by each cardiac exercise cycle is 0.495 microjoules, Energy above the threshold for cardiac pacing.
In another study, the scientists demonstrated an inertia-driven, in-vivo triboelectric nanogenerator (ITENG) capable of using body motion and gravity to generate electrical energy. This ITENG used amine-functionalized polyvinyl alcohol (PVANH2) and perfluoroalkoxy (PFA) as triboelectric materials, successfully operated in animals, and collected real-time output voltage data. The results of the study showed that the device was able to harvest enough energy to charge the pacemaker's battery.
These studies show that the application of TENG technology in cardiac pacemakers has great potential to provide a self-propelled energy solution for pacemakers, reducing the risk and inconvenience of patients needing to surgically replace batteries due to battery depletion. With the further development of technology, more self-powered implantable medical devices may be developed in the future to provide more guarantees for people's healthy life.
3.2.2 Drug delivery systems
The application of TENG technology in drug delivery systems is an area of innovation that powers drug delivery systems by converting biomechanical energy into electrical energy. The following are the applications of TENG technology in drug delivery systems:
1. Targeted therapy:
exploitTENG
technology, researchers have developed advanced drug delivery systems that enable self-regulating, on-demand, and controlled-release drug delivery, especially for targeted therapies such as cancer treatment, wound healing of infections, and tissue regeneration 。
Figure 7(a) Schematic diagram of the mechanism of drug loading and release by electrical stimulation. (b) Electroporation-mediated gene delivery strategies. (c) TENG-mediated electroporation drug delivery system. (d) Stability of Voc over 30,000 cycles.
Muhammad Ikram has developed an advanced triboelectric nanogenerator-driven drug delivery system for targeted therapy, and Figure 7a shows how the TENG system can be precise and on-demand through the use of human heatThe drug is released to the target cells. Figure 7b-c illustrates the self-powered TENG-mediated drug delivery system, including the electroporation-mediated gene delivery strategy and the TENG-mediated electroporation drug delivery system, both of which are indicatedDrug release can be automatically adjusted in response to electrical stimulation. Figure 7d shows the stability of the Voc over 30,000 cycles, demonstrating the stability of the TENG system.
2. Biomechanical Motion-Driven Drug Delivery:
TENG
Technology can convert the energy of human movement into electrical energy that can be used to drive drug delivery devices, such as transdermal drug delivery systems. This self-powered, transdermal drug delivery system enables continuous drug delivery, reducing the risk of peaks and valleys in drug concentrations in the body 。
Figure 8.( a) TENG structural design. (b) Open-circuit voltage stability test chart. (c) Nanoneedle array + TENG. (d) Plane + TENG. (e) Nanoneedle arrays only.
Liu et al. developed a TENG-based electroporation system for in vitro and in vivo drug delivery. The system successfully delivers exogenous materials such as large and small molecules and siRNAs into different cell types, including difficult-to-transfect primary cells, with delivery efficiency and cell viability exceeding 90%. In the study, the TENG disc consisted of a rotor with a radially arranged copper strip as a friction layer, a layer of polytetrafluoroethylene (PTFE) on the stator as another friction material, and a stator with a complementary radially arranged copper layer The strip acts as an electrode (Fig. 8a), a design that allows TENG to generate electrical energy through the triboelectric effect generated by the contact and separation between the copper strip and the PTFE as the rotor rotates. Figure 8b illustrates the stability of the open-circuit voltage of the TENG after 30,000 cycles. This demonstrates the ability of TENG to maintain a stable electrical output over long-term use, which is critical to ensure the continuous operation of the drug delivery system and the consistency of drug delivery. Figure 8c shows that the drug successfully penetrated into the dorsal skin of nude mice at a depth of 23μm after combining TENG and nanoneedle array electrode treatment. In contrast, Figures 8d and 8e show the drug penetration depths using planar electrodes alone plus TENG pulses and nanoneedle array electrodes alone, respectively11μm and 6μm. Comparison of these data shows that the combination of TENG and nanoneedle array electrodes significantly increases the depth of drug penetration by more than three times that of nanoneedle array electrodes alone, thus demonstrating the significant advantages of TENG-driven electroporation systems in improving the efficiency and depth of transdermal drug delivery.
3. Smart Drug Delivery:
The intelligent drug delivery system is a system that realizes the accurate, efficient and safe delivery of drugs through technological innovation, and its application in the medical field is promoting a revolutionary progress.
these systems
By precisely controlling the rate and location of drug release, the therapeutic effect is improved while reducing damage to normal cells and reducing side effects. It can also adjust the dosing strategy according to the patient's specific condition and physiological indicators, and achieve personalized treatment.
Figure 9(a) Formation and drug release processes of MXene-based hydrogel systems. (b) No material, MXene-based hydrogel, Hydrogel@AgNPs, Hydrogel@AgNPs+NIR and other different talentsPhotographs of wound healing processes in diabetic rats at different time points (0, 3, 6, 9, and 12 days) were processed. (c) Statistics of wound area. (d) Number of CD163 cells.
The researchers have developed a hydrogel system based on two-dimensional MXene materials that responds to light and magnetic fields and is able to control the release of drugs. Figure 9a illustrates the system consisting of MXene encapsulated magnetic nanoparticles (MNPs@MXene) and poly(N-isopropylacrylamide)- The hydrogel is composed of alginate (PNIPAM-alginate) double network, and the contraction of the hydrogel is controlled by external stimuli such as NIR radiation and alternating magnetic field, so as to precisely control the drug AgNPof release. The progression of wound healing, including the speed of wound closure and the inflammatory response, can be visually observed in Figure 9b, and Figure 9c shows the wound area statistics of diabetic rats in different treatment groups to quantify the progress of wound healing, Figure 9d shows the number of CD163 cells (a surface marker of macrophages) in different groups to infer an increase or decrease in inflammation, which together demonstrates MXeneThe base hydrogel system has demonstrated desirable therapeutic effects in chronic diabetic wound healing models, particularly in reducing inflammation, promoting tissue regeneration, and angiogenesis.
In summary, the application of TENG technology in drug delivery systems shows great potential and innovation, and provides new ideas and technical support for the development of new self-powered and intelligent drug delivery systems.
3.3 Environmental health monitoring
The application of TENG technology in environmental health monitoring, especially in air and water quality monitoring and microbial disinfection, shows great potential.
3.3.1
Water quality monitoring
Figure 10(a) Structure of the SOS system. (b) Self-powered water texture measurement test excited by the 3-DOF platform. (c-e) Voltage history of the capacitor during self-powered testing. (f, g) Random wave slots. (h.i) The real marine environment. (j, k) Photographs and voltage history of the self-powered sensing process.
TENG technology is used to develop self-powered water quality monitoring systems. For example, Wang et al. invented a multi-tunnel gate electrode for wave energy harvesting and a rolling-mode triboelectric nanogenerator with reverse charge enhancement to monitor water quality by using a self-powered ocean sensing system System, abbreviated as SOS system), the system architecture is shown in Figure 10a, including stacked MO-TENG units, power management modules (PMMs), charging capacitors, voltage regulators, low-power SoCs, long-range communication modules, water quality sensors, and receivers. Figure 10b-e illustrates the self-supplied water quality monitoring performance of the SOS system under external excitation, including the voltage history of the storage capacitor and the charging and discharging cycles of the capacitor during the self-energy sensing process. Figure f-k shows a MO-TENG buoy deployed in a real-world marine environment capable of harvesting wave energy and enabling self-powered water quality monitoring and data transmission through an SOS system. Together, the SOS system uses MO-TENG to collect energy from ocean waves, and uses this energy to drive water quality sensors and wireless communication modules for real-time monitoring and data transmission of water quality.
3.3.2
Microbial disinfection
Figure 11.( a) Schematic diagram of the S-TENG structure. (b) Schematic diagram of the periodic rotation of the S-TENG. (c) Schematic diagram of the rotation speed, output voltage and output current of the S-TENG under manual drive operation. (d) Use various probes powered by S-TENG (N2 gas for ·O2- and H2O2, benzoic acid; BA is used for ·OH and nitrobenzene; NB is used for ·OH and ·Cl) to conduct an oxidized species survey. (e) Schematic diagram of bacterial damage after S-TENG disinfection with Cu3P NW-Cu and Cu3P@SnO2 NW-Cu.
In the field of microbial disinfection, TENG technology is used to develop self-powered disinfection systems. Huo et al. developed a novel disinfection system using a self-powered supercoil-mediated rotational triboelectric nanogenerator (S-TENG) as a power source to drive a novel oxidation-assisted electroporation mechanism, shown in Figure 11aStructure and operating principle of the S-TENG, where 11c particularly demonstrates the ultra-fast rotational speed achieved by the S-TENG under manual drive operation (Fig. 11b) and output voltage and current for inactivation of bacteria and viruses in water. Figure 11d quantifies the type of oxidizing species produced by adding different radical probes to eliminate specific oxidizing species and comparing the disinfection efficiency with and without the addition of these probes. These results confirm that S-TENG is able to generate both enhanced local electric field and oxidizing substances during the disinfection process, achieving efficient disinfection performance. Figure 11d illustrates the in-situ dual staining method, which can be seen using SYTOX Green and PI to distinguish between repairable and fatal damage effects on bacterial membranes The majority of bacteria treated with Cu 3P@SnO2 NW-Cu at fast flow rates (20 mL/min) suffered fatal damage, demonstrating the ability of the S-TENG disinfection method to achieve effective microbial inactivation at fast flow rates through this design。 In summary, the S-TENG water treatment method provides a potential solution to the much-needed water disinfection needs.
4. Advantages and challenges
4.1 Advantages
TENG technology offers several significant advantages in the field of healthcare monitoring, which make it an ideal choice in this field.
(I.) Self-powered features: TENG is able to convert mechanical energy into electrical energy, providing a continuous energy supply for medical and health monitoring equipment, reducing the dependence on traditional batteries, thereby reducing the maintenance cost of equipment and the risk of environmental pollution.
(II.) HIGH SENSITIVITY: TENG'S HIGH SENSITIVITY TO MICRO-MECHANICAL MOVEMENTS ALLOWS IT TO DETECT THE BODY'S WEAK PHYSIOLOGICAL SIGNALS, SUCH AS SMALL CHANGES IN PULSE, BLOOD PRESSURE, AND BODY TEMPERATURE, WHICH ARE ESSENTIAL FOR EARLY DISEASE DIAGNOSIS AND HEALTH MONITORING.
(III.) GOOD BIOCOMPATIBILITY: TENG is typically made of biocompatible materials that can be safely in contact with human tissues, reducing the immune response and inflammation that implantable devices may cause.
(IV.) COST-EFFECTIVENESS: TENG'S RELATIVELY LOW MANUFACTURING COST AND LOW LONG-TERM COST OF USE DUE TO ITS SELF-POWERED NATURE MAKE TENG TECHNOLOGY HAVE A WIDE RANGE OF APPLICATION POTENTIAL IN THE FIELD OF MEDICAL AND HEALTH MONITORING.
(V.) Flexibility and customizability: TENG's structural design is flexible and can be customized according to different application needs, which allows TENG technology to adapt to the design requirements of various medical and health monitoring equipment.
4.2 Challenges
Although TENG technology has significant advantages in the field of healthcare monitoring, it also faces some challenges that require further research and development to overcome.
(I.) Long-term stability: The long-term stability of TENG is the key to its wide application in the field of medical and health monitoring. Material improvements and structural optimization are needed to improve the durability and long-term stability of TENG.
(II.) ENERGY CONVERSION EFFICIENCY: WHILE TENG IS ABLE TO EFFICIENTLY CONVERT MECHANICAL ENERGY INTO ELECTRICAL ENERGY, IN SOME APPLICATIONS, FURTHER ENERGY CONVERSION EFFICIENCY MAY NEED TO BE FURTHER IMPROVED TO MEET THE ENERGY NEEDS OF ENERGY-INTENSIVE MEDICAL DEVICES.
(III.) ENERGY STORAGE AND MANAGEMENT: DESPITE SIGNIFICANT PROGRESS IN ENERGY HARVESTING WITH TENG TECHNOLOGY, HOW TO EFFECTIVELY STORE AND MANAGE THIS ENERGY REMAINS A CHALLENGE. The electrical energy generated by TENG is often intermittent and unstable, which requires the development of efficient energy storage systems and advanced energy management strategies to ensure a continuous and stable power supply.
(IV.) ENVIRONMENTAL ADAPTABILITY: MEDICAL AND HEALTH MONITORING EQUIPMENT MAY BE USED UNDER VARIOUS ENVIRONMENTAL CONDITIONS, AND TENG TECHNOLOGY NEEDS TO HAVE GOOD ENVIRONMENTAL ADAPTABILITY TO ENSURE STABILITY AND PERFORMANCE UNDER DIFFERENT TEMPERATURE, HUMIDITY AND PRESSURE CONDITIONS.
5. Summary and outlook
Triboelectric nanogenerator (TENG) technology has shown great potential in the field of medical monitoring, and its energy harvesting and conversion capabilities have brought new ideas to medical device design. This article reviews the progress of TENG in wearable monitoring devices, implantable medical devices, and environmental monitoring, and discusses its advantages and challenges.
TENG's self-powered nature reduces reliance on conventional batteries, reducing maintenance costs and environmental risks. Its high sensitivity helps to detect weak physiological signals, which is essential for early diagnosis and health monitoring of diseases. TENG's biocompatible materials reduce the risk of immune response and inflammation induced by implantable devices, with low manufacturing and long-term use costs and flexible structural design to accommodate diverse medical needs.
Despite this, the application of TENG in the medical field faces challenges such as stability, energy conversion efficiency and power management. In the future, improvements in TENG technology may involve new materials, intelligent algorithms, and integration with other energy technologies to improve energy efficiency and stability. Combining flexible electronics and nanotechnology, TENG is expected to develop more advanced and versatile medical monitoring devices.
In summary, TENG technology has broad prospects in the field of medical and health monitoring, and it is expected that with the advancement of technology, it will play a more important role in medical monitoring in the future and provide stronger protection for human health.
6. References