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Cited by 164Advanced Sensor and Energy Harvesting MaterialsWireless Body Area NetworksNeuroscience and Neural Engineering

From flexible electronics technology in the era of IoT and artificial intelligence toward future implanted body sensor networks

Open access
Lee, Sanghoon, Shi, Qiongfeng, Lee, Chengkuo·2019·APL Materials
DOI 10.1063/1.5063498
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Abstract

Flexible electronics technology dramatically changes the capability of sensors, which allows us to detect human biological signals not only on the skin but also inside the human body. Wearable sensors that stick to the skin surface can detect various biomechanical movements, biological signals, and byproducts such as useful elements from sweat and body temperature. On the other hand, implantable sensors directly or indirectly contact with biological components inside the body, such as tissue, organs, or muscles, to support or treat bodily functions or problems. With the development of these advanced sensors, we can live together with a huge number of sensors in the future. Toward body sensor networks that can be fully implanted in the future, sustainable energy sources that support the operation of sensors as well as the development of materials that enable long-term use inside the body remain challenges. In this review, we first summarize various state-of-the-art sensors in terms of flexible and wearable platforms. Additionally, we review the recent research trends of energy harvesters in mechanical and thermal energy conversion into useful electricity for the operation of the sensors. Furthermore, we cover recent studies in the aspect of materials for implantable sensors. Finally, we discuss future direction of the sensors that may enable implanted body sensor networks in the body.

AI snapshot

Written from the paper’s full text.

TL;DR

This review surveys flexible electronics for wearable and implantable sensors, stimulators, neural interfaces, and energy harvesters, including biodegradable and 2D-material devices, as steps toward future body sensor networks integrated with IoT and AI. It compiles device examples and performance metrics while noting that direct stimulation using energy harvesters and neural interfaces remains at an infant level.

Key findings

  • Wearable energy harvesters span piezoelectric, thermoelectric, and triboelectric mechanisms: a PZT nanocomposite generator produced 10 V and 1.3 µA for a 3 cm × 3 cm device under bending and 100 V and 10 µA for a 30 cm × 30 cm device under human motions; a PZT thin-film nanogenerator reached ∼200 V and ∼150 µA/cm²; a thermoelectric generator achieved 4.78 mW/cm² at a 25 °C temperature difference; and a stretchable TENG e-skin generated ∼1.16 mW/cm² at 2.3 Hz with up to 600% stretchability.
  • Implantable harvesters demonstrated in vivo or organ-motion tests include a ZnO single-wire generator producing 3 mV and 30 pA from a live rat heartbeat, a PZT ribbon producing ∼4 V on a bovine heart, a PMN-PZT harvester producing 17.8 V and 1.75 µA from porcine heartbeat, an encapsulated iTENG producing 14 V and 5 µA with stability over 72 h, and an iTEAS producing ∼10 V and ∼4 µA from swine heartbeat and breathing.
  • Biodegradable and 2D-material devices include a BD-TENG reaching ∼40 V and ∼1 µA, a gelatin/PLA TENG reaching 500 V, 10.6 mA/m², and 5 W/m² with complete degradation in water in about 40 days, monolayer MoS₂ generating 15 mV and 20 pA under 0.53% strain with 5.08% conversion efficiency, a MoS₂-enhanced TENG reaching 25.7 W/m² (120 times higher than without MoS₂), and a graphene TENG reaching 130 mW.
  • Neural interfaces reviewed include flexible near-field wireless optoelectronic implants, syringe-implanted mesh electronics, flexible microneedle electrodes, e-dura spinal implants, cuff/FINE/TIME peripheral nerve interfaces, and neural dust; the review concludes that combining active neural interfaces with energy harvesting may construct an internal body sensor network.

Methods

  • Design: narrative review of state-of-the-art wearable and implantable devices, from sensors and stimulators to energy harvesters, plus biodegradable and 2D-material-based devices.
  • Data or sample: published literature and prior device demonstrations; no primary human or animal experiments reported by the review itself.
  • Main analysis: qualitative synthesis and comparison of device mechanisms, materials, and reported performance metrics, with figures summarizing representative examples.

Limitations

  • The paper states that direct stimulation using energy harvesters and neural interfaces is still at an infant level, that implantable batteries have limited capacity requiring replacement, and that rigid implant bodies cause mechanical mismatch with tissues.
  • Evident from the text: this is a narrative review without a described systematic search strategy, inclusion/exclusion criteria, or quantitative meta-analysis; the paper does not state limitations of the review itself.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1063/1.5063498

Cites

129 of 129 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 127 cited sources checked · 0 supported · 0 flagged

  • Premisecitation

    The significant transition from typical electronics to flexible electronics started with materials and mechanic and design strategies to match the epidermis.

    “Significant transition from typical electronics to flexible electronics started with materials and mechanic and design strategies to match the epidermis.24,25”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [24] 2011, Science source

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    • cites [25] 2015, Science source

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  • Premisecitation

    Wearable sweat sensors detect physiologically relevant information for non-invasive health monitoring.

    “In addition, wearable sweat sensors detect physiologically relevant information for non-invasive health monitoring [Fig.1(c)]. 2”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [2] 2018, Nat. Electron. source

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  • Premisecitation

    E-skin has demonstrated promising results for applications such as human-machine interface, prosthetics, and medicine.

    “This e-skin has demonstrated promising results for various applications such as human-machine interface, prosthetics, and medicine.6”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [6] 2016, Nature source

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  • Premisecitation

    Energy harvesters with wearable and implantable forms scavenge human body energy into useful electrical energy.

    “To power the wearable and implantable electronics sustainably, another research trend is to develop energy harvesters with wearable and implantable forms that scavenge human body energy into useful electrical energy.[12][13][14][15][16]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [12][13][14][15][16]

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  • Premisecitation

    Advanced 2D materials and biodegradable materials are applied to implantable sensors and energy harvesters to meet requirements of smaller, lighter, higher capacity, and biocompatible materials.

    “Advanced 2D materials as well as biodegradable materials are applied to implantable sensors and energy harvesters to meet these requirements.[20][21][22][23]”
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    • cites [20][21][22][23]

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    Premisecitation

    Advanced bioelectronics with flexible and soft platforms are developed to record biological signals and to stimulate and control organs or nervous systems.

    “For instance, advanced bioelectronics with flexible and soft platforms are developed not only to record biological signals but also to stimulate and control the organs or the nervous systems.[5][6][7][8]”
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    • cites [5][6][7][8]

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    Interpretationreasoning

    The information recorded by wearable electronics allows people to check their body condition and accumulate physiological information, improving the quality of daily life.

    “The information allows people not only to check their body condition but also to accumulate physiological information, improving the quality of daily life.”
    Quote in the paperNot a substantial claim

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    Premisecitation

    Wearable and stretchable electronics can be affixed anywhere in the body and record information such as body temperature, heart rate, and blood pressure.

    “For instance, wearable and stretchable electronics can be affixed anywhere in the body and record information such as body temperature, heart rate, and blood pressure.[1][2][3][4]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [1][2][3][4]

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    Premisenone given

    Flexible electronics technology enables sensors to stick on the human skin or to be implanted inside the human body.

    “Flexible electronics technology enables sensors to stick on the human skin or to implant inside the human body.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationnone given

    Flexible and soft electronics transform bulky and packaged biomedical devices into implantable and biocompatible devices, showing promising prospects for clinical applications.

    “Furthermore, flexible and soft electronics transform bulky and packaged biomedical devices into implantable and biocompatible devices, showing promising prospects for clinical applications.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    A soft, conformal class of device records physiological mechano-acoustic signals from the skin and is capable of heart murmur detection in cardiac patients for advanced clinical diagnostics.

    “Furthermore, a soft, conformal class of device records physiological mechano-acoustic signals from the skin, capable of heart murmur detection in a series of cardiac patients for advanced clinical diagnostics [Fig.1(b)].27”
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    • cites [27] 2016, Sci. Adv. source

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    Premisecitation

    These devices have the capability of mimicking the skin's ability to sense and generate biomimetic signals, which can be embedded on robotic systems.

    “These devices have capability of mimicking the skin's ability to sense and generate biomimetic signals, which can be embedded on robotic systems [Fig.1(a)].26”
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    • cites [26] 2016, Nat. Mater. source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Flexible and soft neural prostheses provide connection between the human nervous systems and devices or robotic systems to replace or enhance sensory, motor, and cognitive modalities.

    “Flexible and soft neural prostheses provide connection between the human nervous systems and devices or robotic systems to replace or enhance sensory, motor, and cognitive modalities of the human.[9][10][11]”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [9][10][11]

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    Interpretationreasoning

    Wearable and implantable energy harvesters may overcome critical challenges of reliable light-weight power sources, bulky size of bioelectronics, and additional external electronics for closed-loop systems.

    “This may overcome the next critical challenges from the aspect of sustainable and long-term use of such devices: (i) reliable light-weight power source with sound output power; (ii) bulky size of bioelectronics when the implants integrate with many active components (such as amplifiers for neural recording and stimulators for neural stimulation); and (iii) additional electronics placed outside the”
    Quote in the paperSubstantial claim

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    Premisecitation

    These devices can be used as sensors or energy sources to stimulate organs or the nervous system.

    “Furthermore, these devices can be used as sensors or energy sources to stimulate organs or the nervous system.[17][18][19]”
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    • cites [17][18][19]

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    Premisecitation

    f-DDM wirelessly receives power and is flexible enough to be implantable on the curved cerebral cortex, delivering two different chemicals or prevention of seizure activity using an anti-epileptic drug.

    “This device wirelessly receives power and is flexible enough to be implantable on the curved cerebral cortex, delivering two different chemicals or prevention of seizure activity using an anti-epileptic drug [Fig.1(d)].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [32] 2018, Nano Energy source

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    Premisereasoning

    Advances in flexible and soft electronics enable conformal interface with soft tissue, organ, and muscles, providing several strategies of therapeutic effect.

    “Advances in flexible and soft electronics enable conformal interface with soft tissue, organ, and muscles, providing several strategies of therapeutic effect.”
    Quote in the paperSubstantial claim

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    Premisenone given

    Implantable devices have limited battery capacity that requires replacement, making patient burden in terms of cost and the risk of surgery.

    “Those have still been used in clinical trials, but there is still limited battery capacity that requires to be replaced, making patient burden in terms of cost and the risk of surgery.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    A pacemaker is invented and implanted in the human body to support heart function.

    “For instance, a pacemaker is invented and implanted in the human body to support heart function.28”
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    • cites [28] 2006, Images Paediatr. Cardiol.

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    Premisecitation

    Photosynthetic bioelectronic sensors are developed to sense touch stimuli and low-intensity ultraviolet radiation and generate electrical power toward self-powered E-skin.

    “In addition, photosynthetic bioelectronic sensors are developed to show that the ability to sense not only touch stimuli but also lowintensity ultraviolet radiation and generate an electrical power toward self-powered E-skin.34”
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    • cites [34] 2018, Adv. Mater. source

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    Premisecitation

    Deep brain stimulation is suggested and demonstrated to activate or inhibit brain signals for neurological diseases such as Parkinson's disease, essential tremor, dystonia, chronic pain, and major depression.

    “Also, deep brain stimulation (DBS) is suggested and demonstrated to activate or inhibit brain signals for neurological disease such as Parkinson's disease, essential tremor, dystonia, chronic pain, and major depression.29,30”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [29] 2008, Neurosci. Biobehav. Rev. source

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    • cites [30] 2004, Invest. Radiol. source

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    Premisecitation

    A biological-cells-inspired energy harvesting skin based on a soft and stretchable TENG has cellular structures of physiological saline interconnected and encapsulated by soft silicone rubber, with stretchability up to 600%.

    “The cellular structures of physiological saline (electrode) are interconnected and encapsulated by soft silicone rubber (triboelectric layer), with an ultrahigh stretchability of up to 600%.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [53] 2017, Nano Energy source

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    Premisecitation

    Another stretchable electronic skin is proposed to detect and harvest various mechanical stimuli, and was the first stretchable energy harvesting e-skin at the time.

    “Another stretchable electronic skin (e-skin) is proposed to detect and harvest various mechanical stimuli, which is the first stretchable energy harvesting e-skin at the time [Fig.2(f)].54”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [54] 2014, Adv. Mater. source

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  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisereasoning

    Fabric or textile based TENGs are developing rapidly due to their wearable, lightweight, washable, and breathable natures.

    “Recently, fabric or textile based TENGs are developing rapidly due to their unique natures of wearable, lightweight, washable, and breathable.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    Triggered by porcine heartbeat motions, the PMN-PZT energy harvester generates an open-circuit voltage and short-circuit current of 17.8 V and 1.75 μA, higher by a factor of 4.45 and 17.5 than previously reported in vivo piezoelectric energy harvesters.

    “Triggered by porcine heartbeat motions, the energy harvester can generate an open-circuit voltage and short-circuit current of 17.8 V and 1.75 µA (higher by a factor of 4.45 and 17.5 than previously reported in vivo piezoelectric energy harvesters), respectively.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [71] 2017, Adv. Funct. Mater. source

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    Premisecitation

    The FDSSCs in the power-textile achieve average power conversion efficiency, open circuit voltage, and short circuit current density of 6%, 0.6 V, and 10.6 mA/cm2, respectively.

    “At the same time, the FDSSCs can achieve an average power conversion efficiency, open circuit voltage, and short circuit current density of 6%, 0.6 V, and 10.6 mA/cm 2 , respectively.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [67] 2016, Adv. Energy Mater. source

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    Premisecitation

    Driven by porcine heartbeats, the iTENG generates an open circuit voltage of 14 V and a short circuit current of 5 μA.

    “Driven by porcine heartbeats, the iTENG can generate an open circuit voltage of 14 V and a short circuit current of 5 µA.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [76] 2016, ACS Nano source

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    Premisecitation

    Neural signals from the brain have been used in applications ranging from medical to engineering fields, such as epilepsy surgery using ECoG and brain computer interface applications using EEG.

    “Such signals were used in various applications ranging from medical to engineering fields, such as an epilepsy surgery using ECoG 88 and brain computer interface applications using EEG.89,90”
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    • cites [88] 2014, Epileptic Disord. source

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    • cites [89] 2015

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    • cites [90] 2005, Neurology source

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  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

    Premisenone given

    Advances in flexible and soft electronics have allowed neural interfaces to better adapt to soft tissue and to apply to a variety of platforms like optoelectronic based interfaces.

    “Advances in flexible and soft electronics have allowed neural interfaces to better adapt to soft tissue as well as to apply to a variety of platforms like optoelectronic based interfaces.”
    Quote in the paperNot a substantial claim

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    Premisecitation

    Due to limitations of EEG and ECoG that cannot obtain signals inside the brain, multi-electrode arrays were designed and demonstrated to be implanted inside the brain using MEMS technologies.

    “Due to the limitations of EEG and ECoG that cannot obtain signals inside the brain, 91 multi-electrode arrays (MEAs) were designed and demonstrated to be implanted inside the brain using microelectromechanical systems (MEMS) technologies.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [91] 2014, Adv. Mater. source

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    Premisecitation

    Driven by the heartbeat and breathing motions of a living swine, the iTEAS produces an open circuit voltage of ∼10 V and a short circuit current of ∼4 μA.

    “Driven by the heartbeat and breathing motions of a living swine, the iTEAS can produce an open circuit voltage of ∼10 V and a short circuit current of ∼4 µA.”
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    • cites [77] 2016, Nano Lett. source

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    Premisecitation

    E-dura implant was developed to insert in the spinal subdural space of rats.

    “E-dura implant was also developed to insert in the spinal subdural space of rats [Fig.3(e)].97”
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    • cites [97] 2015, Science source

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    Premisecitation

    A wireless cuff was suggested, combining reliable cuff interface and mid-field transfer, and modulated a vagus nerve to control heart functions.

    “Accordingly, a wireless cuff was suggested, combining reliable cuff interface and mid-field transfer.This modulated a vagus nerve to control heart functions [Fig.4(h)].108”
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    • cites [108] 2017, PLoS One source

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    Premisecitation

    Advanced neuroprostheses require neural interfaces capable of high quality recording from efferent signals to record intention of movements and reliable stimulation to provide sensory feedback to the brain.

    “For instance, advanced neuroprostheses require neural interfaces capable of the high quality of recording from efferent signals to record intention of any movements as well as capable of reliable stimulation to provide sensory feedback to the brain.99,100”
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    • cites [99] 2018, Curr. Opin. Biomed. Eng. source

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    • cites [100] 2018, Adv. Healthcare Mater. source

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    Premisecitation

    Ag nanowires and polyvinylpyrrolidone are added to the nanoparticle-silk composite to enhance dispersion of nanoparticles and prevent Ag nanowires from connecting.

    “Ag nanowires and polyvinylpyrrolidone are also added to the nanoparticle-silk composite, with the function of enhancing the dispersion of the nanoparticles and preventing Ag nanowires from connecting, respectively.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [113] 2015, Nano Energy source

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    • Rests on an assumption: Biodegradability is of great importance for implantable energy harvesters, especially in short-term applications where no further surgical procedure is required to remove the implantable device.

  • May combine two claims.

    Premisecitation

    Triggered by a foot stepping motion, the biodegradable nanogenerator achieves a maximum output voltage of 2.2 V and a current density of 0.12 μA/cm2.

    “Triggered by a foot stepping motion, a maximum output voltage of 2.2 V and a current density of 0.12 µA/cm 2 can be achieved.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [113] 2015, Nano Energy source

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    • Rests on an assumption: Biodegradability is of great importance for implantable energy harvesters, especially in short-term applications where no further surgical procedure is required to remove the implantable device.

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    Premisecitation

    The open circuit voltage and short circuit current of the BD-TENG can reach up to ∼40 V and ∼1 μA, respectively.

    “The open circuit voltage and short circuit current of the BD-TENG can reach up to ∼40 V and ∼1 µA, respectively.”
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    • cites [114] 2016, Sci. Adv. source

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    • Rests on an assumption: Biodegradability is of great importance for implantable energy harvesters, especially in short-term applications where no further surgical procedure is required to remove the implantable device.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisenone given

    Recently, two-dimensional materials have attracted increasing research effort due to their unique property of a single layer of atoms.

    “Recently, two-dimensional (2D) materials have attracted increasing research effort due to their unique property of a single layer of atoms.”
    Quote in the paperNot a substantial claim

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    Premisecitation

    Single-layer MoS2 has a strong intrinsic piezoelectric response because of broken inversion symmetry, while bilayers and bulk crystals are non-piezoelectric due to the centrosymmetric structure.

    “The results indicate that single-layer MoS 2 has strong intrinsic piezoelectric response because of the broken inversion symmetry, while the bilayers and bulk crystals are non-piezoelectric due to the centrosymmetric structure.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [120] 2014, Nature source

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    Premisecitation

    Through optimizing the contact surfaces and thickness of the gelatin and PLA films, a maximum output voltage, short circuit current density, and power density of 500 V, 10.6 mA/m2, and 5 W/m2 can be achieved with a device size of 4 cm × 4 cm.

    “Through optimizing the contact surfaces and thickness of the gelatin and PLA films, a maximum output voltage, short circuit current density, and power density of 500 V, 10.6 mA/m 2 , and 5 W/m 2 can be achieved, respectively, with a device size of 4 cm × 4 cm.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [116] 2018, Nano Energy source

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    • Rests on an assumption: Biodegradability is of great importance for implantable energy harvesters, especially in short-term applications where no further surgical procedure is required to remove the implantable device.

  • May combine two claims.

    Premisecitation

    The corresponding power density and mechanical-to-electrical energy conversion efficiency are 2 mW/m2 and 5.08%, respectively.

    “The corresponding power density and the mechanical-to-electrical energy conversion efficiency are 2 mW/m 2 and 5.08%, respectively.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [120] 2014, Nature source

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    Premisereasoning

    The fabricated TENG with the MoS2 layer can produce a peak power density up to 25.7 W/m2, which is 120 times higher than that without the MoS2 layer.

    “As a result, the fabricated TENG with the MoS 2 layer can produce a peak power density up to 25.7 W/m 2 , which is 120 times higher than that without the MoS 2 layer.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [123] 2017, ACS Nano source

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    Premisecitation

    Under a temperature gradient of -35 K, the MoS2/graphene based nanogenerator can generate an output voltage of -0.73 mV and a power density of 8.8 nW/cm2.

    “Under a temperature gradient of -35 K, the MoS 2 /graphene based nanogenerator can generate an output voltage of -0.73 mV and a power density of 8.8 nW/cm 2 .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [122] 2017, Semicond. Sci. Technol. source

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    Premisecitation

    The TENG with monolayer (1L) graphene can produce a voltage of 5 V and a current density of 500 nA/cm2.

    “The TENG with monolayer (1L) graphene can produce a voltage of 5 V and a current density of 500 nA/cm 2 .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [126] 2014, Adv. Mater. source

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  • Classified as probably not a substantial claim.

    Interpretationreasoning

    Using diversified flexible electronics can create sensors, actuators, stimulators, energy harvesters, and/or integrated systems, for wide applications ranging from wearable to implantable electronics.

    “From the research trends of flexible electronics technology, using diversified flexible electronics can create sensors, actuators, stimulators, energy harvesters, and/or integrated systems, for wide applications ranging from wearable to implantable electronics.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    For regularly stacked graphene TENG, the generated voltage and current density can be increased to 9 V and 1.2 μA/cm2, respectively.

    “For regularly stacked graphene TENG, the generated voltage and current density can be increased to 9 V and 1.2 µA/cm 2 , respectively.”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [126] 2014, Adv. Mater. source

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    Premisecitation

    A conformal graphene based TENG is demonstrated with a total thickness of less than 2.4 mm and good adhesion ability on the human skin.

    “A conformal graphene based TENG is demonstrated with a total thickness of less than 2.4 mm and good adhesion ability on the human skin [Fig.6(d)].124”
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    • cites [124] 2016, Nano Energy source

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  • The paper relies on this without support.

    Biodegradability is of great importance for implantable energy harvesters, especially in short-term applications where no further surgical procedure is required to remove the implantable device.

    “For implantable energy harvesters, biodegradability is of great importance especially in short-term application where no further surgical procedure is required to take out the implantable devices.”

  • The paper relies on this without support.

    The brain is not fully understood and is a research area that needs further exploration.

    “Despite of extensive research on the brain, the mystery of the brain has not yet been fully understood, and it is a research area that needs to be further explored.”
2 of 2

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Implantable sensors are designed to interact with biological components for support and treatment of bodily functions and mental health monitoring.

    “Implantable sensors represent a frontier in healthcare, designed to interact with biological components for support and treatment of bodily functions and mental health monitoring [245,246].”

    From The emergence of AI-based wearable sensors for digital health technology: a review (2023) · cites this paper as [245]

Cites

Flagged first, then by citations

Research works printed but not linked: 3

  1. 2006, Images Paediatr. Cardiol., 8, 17
  2. 2004, Neuroprosthetics: Theory and Practice
  3. 2015, Wiley Encyclopedia of Electrical and Electronics Engineering

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Related

Authors
Lee, S., Shi, Q., & Lee, C.
Affiliations
National University of Singapore (SG)
Corresponding author
Lee, Chengkuo
ORCID
Venue
APL Materials
Publisher
AIP Publishing
Published
2019-02-06
Volume
7
Issue
3
ISSN
2166-532X (ISSN-L)
DOI
10.1063/1.5063498
OpenAlex
W2912990980
Cited by
164
References
129
Citations by year
2026: 10 · 2025: 18 · 2024: 16 · 2023: 16 · 2022: 38 · 2021: 22 · 2020: 30 · 2019: 14
FWCI
9.18
Type
journal article
Language
en
Open access
Licence
Locations
  • APL Materials (publishedVersion, cc-by)
  • National University of Singapore (submittedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • A*STAR and NCBR Joint Grant (R-263-000-C91-305)
  • DGIST Start-up Fund (ICT 2018090020)
  • Faculty Research Committee Singapore (R-263-000-B56-112)
  • NUS HiFES (R-263-501-012-133)
  • National Research Foundation Singapore (NRF-CRP10-2012-01, NRF-CRP8-2011-01)
Topics
  • Physical Sciences › Engineering › Biomedical Engineering › Advanced Sensor and Energy Harvesting Materials
  • Physical Sciences › Engineering › Biomedical Engineering › Wireless Body Area Networks
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neuroscience and Neural Engineering
Keywords
flexible electronics, wearable sensors, implantable sensors, wireless body area networks, energy harvesting, mechanical energy conversion, thermal energy conversion, implant materials, biological signals, Internet of Things, artificial intelligence

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Claims read by deepseek-v4.1-flash under definition version 3 (extract-v3) on 2026-10-09.

Classified by jev-1.13-20260917 (gold-guideline-v0.2) on 2026-10-09.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

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