An implantable device for monitoring human health and various health conditions

Abstract

Disclosed is an apparatus comprising an electrochemical sensor for detecting at least one analyte and a near field communication (NFC) interface for transcutaneously communicating information detected by the electrochemical sensor.

Description

Technical Field

[0001] The present disclosure relates to devices, apparatuses, systems, and approaches for detecting analytes, and more particularly, but not limited to, implantable devices for detecting analytes within a human body.

Background Art

[0002] Physiological monitoring is fundamental in the diagnostic, prognostic, and progression assessment of many medical conditions (e.g., cardiovascular, nervous, muscular, endocrine, etc.). Conventionally, parameters and physiological substances related to such conditions have been monitored using body surface measurements with devices such as electrodes.

Summary of the Invention

Problems to be Solved by the Invention

[0003] However, there is a need for improved approaches for on-demand monitoring of analytes within a subject or patient, and particularly for improved approaches for detecting analytes within the tissues of a subject.

Means for Solving the Problems

[0004] The invention is set forth in the claims.

Brief Description of the Drawings

[0005] Specific embodiments will be exemplified with reference to the drawings.

[0006]

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[0007] Disclosed herein is an implantable device or apparatus arranged to be entirely implanted subcutaneously, the device comprising an electrochemical sensor for detecting at least one analyte and a near field communication (NFC) interface for transcutaneous (or transdermal) communication of information detected by the electrochemical sensor.

[0008] Conventional commercially available implants have been used for the detection and / or delivery of electrical stimulation via biopotential channels (or electrodes) and typically do not perform electrochemical detection of analytes. Conventional implants are typically battery-powered.

[0009] The implantable devices and / or apparatuses disclosed herein are advantageously arranged to be implanted subcutaneously for the electrochemical detection of analytes and perform physiological data detection at the tissue level. In particular, the implantable device and / or apparatus may be fully implanted subcutaneously in the human body, such as within the torso of the human body. Thus, the detection performed by the implantable device provides a "cellular-level" monitor of chemical and biological signals generated at the tissue level, such as within interstitial fluid. The presence and / or concentration of chemical and / or biological analytes may be detected and / or measured. In some examples, the analyte of interest is indicative of human reproductive ability.

[0010] Furthermore, the approach used herein utilizes an NFC interface. Advantageously, the NFC interface enables communication of information sensed by an electrochemical sensor transcutaneously, i.e., across the skin barrier. The NFC interface enables an implanted device to wirelessly receive power from an external power source without relying on a battery. The external power source may be a mobile phone or other NFC interface arranged to supply power to the implanted device and receive data transmitted from the implanted device using NFC. The implanted device may have a microcontroller arranged to encrypt data. The NFC interface enables transcutaneous, i.e., across the subject's skin, power reception when the implanted device is fully implanted subcutaneously, and the NFC interface is also arranged to wirelessly transmit data transcutaneously.

[0011] As used herein, the term "chemical sensor" is also used when referring to the type of electrochemical sensor.

[0012] The implanted device may be based on and / or comprise a printed circuit board.

[0013] FIG. 1 shows an example of a printed circuit board 100. The printed circuit board (PCB) is based on conventional materials such as FR4 and copper. Components of the implanted device may be attached to the printed circuit board 100 with electronic pads 101, 103, etc. Another set of electronic pads 105, 107, 109 are each functionalized to function as a chemical sensor or an electrochemical sensor, as will be further described later in connection with FIG. 2.

[0014] Each of the electronic pads 101, 103, 105, 107, 109 has a nickel-gold layer or simply a gold layer arranged to function as a conductive layer. Each of the electronic pads 101, 103, 105, 107, 109 of the PCB 100 does not have a solder mask process applied to it like a normal PCB and like other parts of the PCB. Instead, gold and / or nickel is simply applied to the exposed copper of the PCB 100.

[0015] The components of the embedded device attached to the printed circuit board 100 include an NFC tag, an NFC antenna, a microcontroller, at least one amplifier, and at least one resistor. Each component will be further described in relation to the embodiments described below. Any of the components may be mounted on either side of the PCB. In some embodiments, only one side of the PCB may be used in this way, and in other embodiments, both sides of the PCB may be used in this way.

[0016] The PCB 100 is also characterized by conductive traces 111 that are coated by a standard solder mask (silk screen) process. As will be understood, the conductive traces 111 not shown in FIG. 1 enable connecting various components across the PCB. The copper traces may have a width of 0.1 mm. The PCB may similarly include copper pools and copper plated vias.

[0017] FIG. 2 shows a cross-section of a part of the embedded device. The printed circuit board 100 of FIG. 1 is shown in FIG. 2 and has an exemplary thickness of 1000 μm. An electronic pad 200 comprising an exemplary nickel layer 202 with a thickness of 6 μm and an exemplary gold layer 204 with a thickness of 2 μm is arranged on the printed substrate. The electronic pad may be formed in the exposed copper area of the PCB by a technique such as electroplating. The nickel layer is arranged on top of the copper of the PCB, and the gold layer is arranged on top of the nickel layer. In other examples, the nickel layer may be omitted, or layers of different thicknesses or orders may be used.

[0018] A chemical sensor 250 is formed on the electronic pad. The chemical sensor comprises four layers: nanoparticles 252, an internal barrier layer 254, an immobilized sensing membrane (receptor) 256, and a diffusion membrane 258. Accordingly, the electronic pad is "functionalized" as a chemical sensor for detecting analytes, like the electronic pads 105, 107, 109 in FIG. 1. Although not shown in FIG. 2, there are pads for connecting electrical components such as amplifiers to the PCB. These pads may also have a nickel layer and a gold layer disposed thereon, as in the example of FIG. 2. The mixing and thickness of the gold layer and the nickel layer determine the quality of the electrical connection with the functionalized sensing layer disposed thereon.

[0019] The diffusion membrane 258 of the chemical sensor 250 enables the analyte to diffuse into the sensor. The analyte diffuses across the diffusion membrane 258 and is retained by the immobilized sensing membrane 256. Here, the analyte interacts with the chemical sensor 250 to generate an electrical change or signal. The electrical signal is enhanced by the presence of the nanoparticles 252.

[0020] In each embodiment, the functionalized chemical sensor may function as an electrode of a sensing and / or measuring circuit, and the "electrode" is functionalized to respond to chemical analytes by the deposition of specific sensor layers (as described above) through an electrochemical process. The chemical sensor may be formed to target and / or detect specific chemical and / or biological analytes such as pH, sodium, calcium, potassium, lactate, glucose, cortisol, estrogen, progesterone, and / or luteinizing hormone (LH).

[0021] The materials and layer thicknesses of the functionalized chemical sensor are selected to achieve the highest sensitivity for the target chemical analyte. Exemplary materials are shown in Table 1. For example, for detecting pH, the diffusion membrane material may be chitosan, the immobilized sensing membrane (receptor material) may be iridium oxide nanoparticles, and so on.

Table 1

[0022] When nanoparticle 252 is used as a component of the sensing layer, the sensitivity of the electrochemical sensor is significantly improved. Nanoparticles are not only adopted for electrode surface modification, signal molecule labeling (specific target binding), and signal amplification, but also used as catalysts for ongoing chemical reactions. Nanoparticles are excellent in biocompatibility and enhance the surface activity of the electrode. Therefore, they improve the electron transfer ability of the electrode, immobilize bioactive substances on the electrode surface, and shorten the detection time. The nanoparticle 252 to be used can have different sizes (within the nanometer range) and shapes (such as spherical, cylindrical, planar, etc.), and noble metal nanomaterials (such as gold and silver), semiconductor materials (quantum dots), carbon nanomaterials (carbon nanotubes), graphene oxide, composite nanomaterials, etc. can be used. Therefore, there are multiple methods for depositing nanoparticles according to the type of nanomaterial to be adopted and the substrate surface to which they are attached. Examples include dip coating, spin coating, solvent evaporation method, chemical vapor deposition method, transfer printing method, etc.

[0023] In some examples, nanoparticle 252 may be omitted, and chemical sensor 250 may include three layers: an internal selection layer, an intermediate sensing layer, and an external biocompatible layer.

[0024] Figure 3 shows a cross-section of the implantable device 300. The implantable device 300 is based on a PCB 310 similar to the PCB 100 in FIGS. 1 and 2. Similar to FIGS. 1 and 2, a chemical sensor 312 is formed on the electronic pads of the PCB. Electronic components 320, 330, 340, 350 such as amplifiers, resistors, and / or NFC tags are also attached to the electronic pads of the PCB.

[0025] The implantable device 300 is characterized by an outer layer of a seal 360. The seal 360 is made of a biocompatible material, ensuring that the implantable device 300 functions without being rejected by the subject's body. The seal 360 is provided with micropores so that the chemical sensor can access the physiological medium. The micropores may be formed by laser patterning of the seal 360 or another appropriate technique.

[0026] The embedded device 300 also includes an NFC antenna 370. In one example, the NFC antenna 370 is wound around the PCB 310.

[0027] NFC technology enables energy transfer between an embedded device and an NFC-enabled external device that is in close enough proximity. Thus, no wiring, battery, and separate electronics are required to power the embedded device. Instead, the NFC antenna 370 obtains power or energy from the incident magnetic field.

[0028] A device with an NFC chip can power the embedded device. Preferably, by using encryption, unauthorized devices are prevented from accessing data from the device.

[0029] In the embodiment of FIG. 3, only one chemical sensor 312 is shown, but in other embodiments, the embedded device may feature multiple chemical sensors. The multiple chemical sensors may each be of the same type or of different types from each other. For example, one chemical sensor may be arranged to perform amperometry, and another chemical sensor may be arranged to perform voltammetry. Thus, the embedded device can perform two techniques, amperometry and voltammetry, and further, can perform the two techniques simultaneously. The embedded device may be arranged to perform detection based on the impedance of the analyte.

[0030] In such a device, two or more different analytes may be measured at the same time. Examples of analytes that can be measured by the devices and apparatuses disclosed herein are pH, sodium, calcium, potassium, lactate, luteinizing hormone, glucose, cortisol, estrogen, and progesterone. In an example where the embedded device is arranged to perform amperometry and voltammetry, the analyte may be arranged to simultaneously detect one of pH, sodium, calcium, and potassium (using voltammetry) and one of lactate, glucose, and cortisol.

[0031] Figure 4 shows an embedding example of the implantable device disclosed in this specification. Figure 4 is a scanning electron microscope (SEM) image 400 of such an implantable device. It shows a PCB 402 that characterizes the implemented electronic components. It also shows an NFC antenna 404 formed of a copper wire wound 20 times around the outer periphery of the PCB. In contrast, a sealing layer 406 is also shown. In this example, the sealing layer comprises polydimethylsiloxane (PDMS, thickness 1 mm) and parylene (thickness 100 μm). Both of these materials are biocompatible. In other examples, other biocompatible materials may be used for the sealing layer. Advantageously, the sealing layer 406 protects the internal components of the implantable device and extends the life of the device.

[0032] As an example, the implantable device may be based on a PCB having a surface area of 3.7 mm ×  6.5 mm. In some examples, the implantable device may be injected into the target tissue through a needle, as a result of which some of the technical constraints imposed by the medical surgical approach are alleviated.

[0033] Figure 5 shows a schematic of an electronic circuit 500 for an implantable device. The electronic circuit 500 is suitable for implementation in the PCB-based implantable device disclosed in this specification.

[0034] The electronic circuit 500 includes a microcontroller 501. The microcontroller is arranged to control other components of the electronic circuit 500 and process information for communication. For example, the microcontroller is arranged to communicate with an NFC tag 503. The NFC tag 503 is arranged to transmit data using the NFC communication protocol, and the microcontroller may be used to encrypt the data. The NFC tag 503 forms an NFC interface together with an NFC antenna 505. The circuit 500 can receive power wirelessly from an external power source by means of the NFC antenna 505. In other words, there is no active power source (such as a battery) within the electronic circuit 500, and in this regard, the electronic circuit 500 can be regarded as a passive circuit.

[0035] The electronic circuit 500 is arranged to perform voltammetry using a first voltammetry working electrode 507 and a second voltammetry working electrode 509. The voltammetry working electrodes may be functionalized to the chemical sensors described herein, as in the example of FIG. 2. The voltammetry portion of the electronic circuit 500 also includes a first amplifier 511 and a second amplifier 513 for each voltammetry working electrode 507, 509. The amplifiers may be mounted on a PCB as described herein. Each amplifier 511, 513 is connected to appropriate value resistor portions 515, 517, 519, 521 and arranged to amplify the electrical signals generated by the working electrodes 507, 509, as will be understood by those skilled in the art. Commercially available dual amplifiers may be used for the amplifiers 511, 513.

[0036] The electronic circuit 500 is also arranged to perform amperometry and, in some examples, may perform amperometry simultaneously with voltammetry. The electronic circuit 500 is arranged to perform amperometry using a first amperometric working electrode 531, a reference electrode 533, and a counter electrode 535. In some examples, the three electrodes 531, 533, 535 are considered to form a single chemical sensor and may be functionalized as described herein, as in the examples of FIGS. 2 and 3. The first amperometric working electrode is connected to an amplifier 537, which has a resistor 538 connected across it. The reference electrode 533 and the counter electrode 535 are connected to another amplifier 539. A commercially available dual amplifier may be used for amplifiers 537, 539. Amplifiers 537, 539 are arranged to amplify the electrical signals generated by the (one or more) electrodes.

[0037] Returning to the chemical sensor 312 of FIG. 3, such a chemical sensor may, in some examples, be arranged to be divided into different "electrodes" that correspond to those of the electronic circuit 500. For example, the chemical sensor may be arranged to provide three electrodes for amperometry, namely a first amperometric working electrode 531, a reference electrode 533, and a counter electrode 535, as described above in connection with the electronic circuit 500. A similar arrangement may be used for voltammetry using the same chemical sensor or an additional chemical sensor. In such an embodiment, the seal 360 has a structure corresponding to the micropores so that the interstitial fluid and / or tissue in which the separate "electrodes" of the chemical sensor 312 are detected can be accessed.

[0038] In some examples, the reference electrode 533 and the counter electrode 535 may be used in combination with voltammetry electrodes to generate signals based on the presence of the analyte.

[0039] The electronic circuit 500 shown in FIG. 5 can measure up to three chemical analytes simultaneously. One acquisition channel is attached using the amperometry circuit topology described above (targeting, for example, lactate or glucose, cortisol, etc.), and the other two acquisition channels are attached using the voltammetry circuit topology described above (targeting, for example, pH or sodium, potassium, calcium, etc.). Each acquisition channel is connected to an individual working electrode, and the counter electrode and reference electrode are shared among the three acquisition channels. Each acquisition channel may be described as an ion sensing channel.

[0040] The electronic circuit 500 is arranged to amplify the voltage signal and / or current signal from the channel and convert it into digital samples acquired by an embedded microcontroller prior to secure wireless transmission using the NFC protocol.

[0041] As will be appreciated, the components of the electronic circuit 500 may vary. What is important is that the electronic circuit 500 uses a chemical sensor placed on the electrode to perform voltammetry and / or amperometry of the analyte and transmit the measurement data using NFC. Alternatively or additionally, the electronic circuit 500 may be arranged to perform impedance detection of at least one analyte.

[0042] In some examples, the electronic circuit 500 can detect any combination of voltammetric (pH, sodium, calcium, potassium, etc.) and amperometric (lactate, glucose, cortisol, etc.) analytes when the electrodes are chemically functionalized to respond to such stimuli.

[0043] In some examples, miniaturization of the sensor means that different sensing parts can detect the same analyte or different analytes from each other.

[0044] The electronic circuit 500 is arranged to also perform cross-checks between sensors. Indicators of signal magnitude, interference, and drift are defined within programming code executed within the microcontroller. Deviations from the typical calibration curves for each single analyte and the influence of external factors (such as temperature) are also recorded and may be wirelessly transmitted to the user.

[0045] FIG. 6 shows an example of an NFC data communication packet 600 suitable for transmitting data via the NFC interface of the embedded device disclosed herein. The data is transmitted or received using the NFC tag of the NFC interface, and the power is received using the NFC antenna of the NFC interface.

[0046] The NFC interface is arranged to communicate with a device such as a tablet or mobile phone for environmental power generation and data communication.

[0047] The NFC data communication packet 600 includes a preamble 601, a data stream 602, and an integrity check field 605.

[0048] The preamble 601 includes a universal data preamble that functions as a handshake protocol between two entities involved in the communication. The data stream 602 includes the payload (appropriate data) to be transmitted. The fields of the data stream 602 may be of a size of 1 kB in plain form or may be encrypted. As will be described later in connection with the example of FIG. 7, the payload is encrypted inside the microcontroller, and thus cannot be decrypted unless another NFC receiver knows the decryption cipher. Only the data preamble 601 is completely transparent between NFC entities.

[0049] The integrity check field 605 is a 16-bit cyclic redundancy check for avoiding the transmission and reception of damaged data packets.

[0050] The fact that the NFC protocol generates a high-frequency signal to transmit communication packets means that the energy emitted by this process can be used by other nearby NFC devices for wireless charging (environmental power generation). The embedded device itself may also be powered in this way. The NFC antenna of the embedded device disclosed in this specification is arranged such that the embedded device can be sufficiently wirelessly and environmentally powered from the radio frequency electromagnetic field generated by a mobile phone at intervals up to, for example, 2 cm.

[0051] In some examples, the NFC communication function of the NFC interface is based on standard communication protocols (ISO / IEC 14443 and ISO / IEC 18000-3) established for NFC. Thus, external devices compliant with this standard can power the embedded device.

[0052] With the NFC communication protocol, the embedded device can transfer, for example, a larger amount of data in one transmission packet than RFID communication. By using NFC, up to 1 kB equivalent of physiological data can be exchanged in each exchange with an external device, while current RFID technology can only transfer dozens of bytes, half of which is used for the wireless transmission of the chip identification number and signal communication flags. Furthermore, since the power intensity of the radio frequency assigned to RFID technology is lower than that of NFC, the communication distance between the embedded device and the external device is reduced.

[0053] FIG. 7 shows an exemplary method 700 for encrypting data such as measurement data provided by a chemical sensor. The encrypted data is transmitted using the NFC interface. The method 700 for encrypting data is a lightweight algorithm, that is, it is intended for low-power implementation in the embedded devices disclosed in this specification. The method 700 enables the data transmitted by the NFC tag of the embedded device to be decrypted only by an authenticated external device. The authenticated external device can, in some examples, comprise a synchronized application.

[0054] Method 700 is divided into three sequential protection layers and generates a combination of codes of approximately 2 to the 45th power.

[0055] In a first step 701, the method comprises encrypting data in a session_cypher step. The session_cypher step is an XOR operation between an 8-bit fixed_cypher variable shared by an embedded device and an authenticated external device (in some examples, via a synchronization application on a mobile phone), and a one-time random_cypher variable generated by the embedded device each time an NFC transmission occurs. The "synchronization" application shares the same fixed_cypher as the embedded device, thereby being able to decrypt the encrypted data transmitted from the embedded device. In some implementations, only one embedded device and one application share a unique fixed_cypher. The fixed_cypher is once hard-coded into the non-volatile memory (inside the microcontroller) of the embedded device during device programming at the manufacturing stage and is also hard-coded into the programming code of the application before being installed on the selected external device, thereby "synchronizing" with the embedded device. The specification and software template can be used by an authorized technician to install the "synchronization" application in one external device, and then both the specification and software template are discarded so that they are not used in other external devices. Similar applications that do not share the same fixed_cypher as a particular embedded device cannot decrypt the data from the embedded device because they are not "synchronized" in this way.

[0056] In a second step 702, the method comprises encrypting data by means of a look-up table (LUT) entry. The second step 702 comprises an XOR operation between a single 16-bit pattern included within a LUT containing 64 mutually different pattern entries. The LUT is hard-coded in the non-volatile memory of the embedded device and the synchronized application and is unique to each embedded device. A specific LUT entry among the 64 mutually different entries used during the encryption by the embedded device is restored by a "synchronized" application by manipulating a bitstream encoded by a combination of a fixed_cypher and a part of a session_cypher. The number of entries 64 is used as an example based on the capacity of an exemplary non-volatile memory of the microcontroller of the embedded device. In this example, the 64 entries occupy (2^6 * × 16 bits / 8) = 128 bytes or 128 address positions. In other examples, a smaller number of entries or a larger number of entries may be used depending on the available memory capacity.

[0057] In a third step 705, the method comprises hopping of NFC memory addresses. The third step 705 comprises randomly assigning chunks of data bits to non-consecutive contiguous address blocks inside the NFC tag before transmission. A single communication channel is used and the entire data stream is divided into chunks of bits assigned to mutually different random address positions within the NFC tag memory, thereby breaking the continuity of the data stream for each transmission. The original continuous stream can only be reassembled by a synchronized external device.

[0058] FIG. 8 shows a method 800 for detecting an analyte, the method being performed using the embedded devices and devices disclosed herein as in the embodiments of FIGS. 2-7 when the embedded devices and devices are implanted subcutaneously as a whole.

[0059] In a first step 801, the method comprises detecting at least one analyte using an electrochemical sensor.

[0060] In a second step 803, the method comprises transmitting information detected by the electrochemical sensor using an NFC interface.

[0061] As described above in connection with the placement of the implantable device, the method may further comprise detecting a plurality of analytes simultaneously using an electrochemical sensor.

[0062] As described above in connection with the placement of the implantable device, the method may further comprise performing voltammetry and amperometry simultaneously.

[0063] As described above in connection with the placement of the implantable device, the method may further comprise detecting at least one of pH, sodium, calcium, potassium, lactate, luteinizing hormone, glucose, cortisol, estrogen, and progesterone.

[0064] As described above in connection with the placement of the implantable device, the method may further comprise detecting simultaneously one of pH, sodium, calcium, and potassium and one of lactate, glucose, and cortisol.

[0065] As described above in connection with the placement of the implantable device, the method may further comprise generating ambient power from an electromagnetic field using an NFC interface.

[0066] As described above in connection with the placement of the implantable device, the method may further comprise detecting at least one analyte indicative of human fertility.

[0067] As described above in connection with the placement of the implantable device, the method may further comprise encrypting the information sensed by the electrochemical sensor prior to communicating it transcutaneously. In some examples, the encryption is performed using the method 700 of FIG. 7.

Claims

1. A device that is positioned so that the entire device is implanted under the skin, An electrochemical sensor that detects at least one analyte, A near-field communication (NFC) interface that transmits information detected by the electrochemical sensor transcutaneously, A device equipped with the following features.

2. The apparatus according to claim 1, wherein the electrochemical sensor is arranged to detect multiple analytes simultaneously.

3. The apparatus according to claim 1, wherein the NFC interface is a passive component.

4. The apparatus according to claim 1, wherein the electrochemical sensor comprises a selection layer, a detection layer, and an external biocompatible layer.

5. The apparatus according to claim 1, wherein the electrochemical sensor is located on a pad of a printed circuit board.

6. The apparatus according to claim 5, wherein the pads of the printed circuit board are not covered with a solder mask.

7. The apparatus according to claim 5, wherein the pad comprises a contact layer containing gold.

8. The apparatus according to claim 7, wherein the contact layer further comprises nickel.

9. The apparatus according to claim 1, wherein the electrochemical sensor is arranged to perform voltammetry and amperometry simultaneously.

10. The apparatus according to claim 1, which is configured to perform impedance detection on at least one object to be analyzed.

11. The apparatus according to claim 1, wherein the electrochemical sensor is arranged to detect at least one of pH, sodium, calcium potassium, lactic acid, luteinizing hormone, glucose, cortisol, estrogen, and progesterone.

12. The electrochemical sensor is pH, sodium, calcium, and potassium (one of these) One of lactic acid, glucose, and cortisol, The apparatus according to claim 1, which is arranged to detect simultaneously.

13. The apparatus according to claim 1, wherein the NFC interface is arranged to generate energy from an electromagnetic field.

14. The apparatus according to claim 1, which does not include a battery.

15. The apparatus according to claim 1, wherein the electrochemical sensor is arranged to detect at least one analyte indicating human reproductive capacity.

16. The apparatus according to claim 1, further comprising an amplifier arranged to amplify the signal generated by the electrochemical sensor.

17. The apparatus according to claim 1, wherein the information detected by the electrochemical sensor is configured to be encrypted before being transmitted transcutaneously.

18. A method for detecting an object to be analyzed, which is performed in the apparatus described in claim 1 when the apparatus described in claim 1 is entirely implanted subcutaneously. Using the aforementioned electrochemical sensor, detect at least one substance to be analyzed, Using the NFC interface, information detected by the electrochemical sensor is transmitted, A method for providing this.

19. The method according to claim 18, further comprising simultaneously detecting multiple analytes using the electrochemical sensor.

20. The method according to claim 18, further comprising performing voltammetry and amperometry simultaneously.

21. The method according to claim 18, further comprising detecting at least one of pH, sodium, calcium potassium, lactic acid, luteinizing hormone, glucose, cortisol, estrogen, and progesterone.

22. pH, sodium, calcium, and potassium (one of these) One of lactic acid, glucose, and cortisol, The method according to claim 18, further comprising simultaneously detecting the same.

23. The method according to claim 18, further comprising generating energy from an electromagnetic field using the NFC interface.

24. The method according to claim 18, further comprising detecting at least one analyte indicating human fertility.

25. The method according to claim 18, further comprising encrypting the information detected by the electrochemical sensor before transmitting it transcutaneously.

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