WO2022164265A1

WO2022164265A1 - Flexible and lightweight transcutaneous oxygen partial pressure sensor capable of wireless telecommunication

Info

Publication number: WO2022164265A1
Application number: PCT/KR2022/001607
Authority: WO
Inventors: 박진우; 임창진; 로스엠마누엘트라이엠블로; 전준우
Original assignee: 연세대학교 산학협력단
Priority date: 2021-02-01
Filing date: 2022-01-28
Publication date: 2022-08-04
Also published as: KR20220111205A

Abstract

The present invention relates to a flexible and lightweight transcutaneous oxygen partial pressure sensor capable of wireless telecommunication. More specifically, this sensor is characterized by comprising: a sensor unit which has one side surface contacting part of the human body and provides a sensing signal with respect to the oxygen partial pressure in the human body; a signal processing unit which is connected to the sensor unit and generates sensing information; a wireless communication unit for wirelessly transmitting the sensing information; and a power supply unit that is a battery for supplying electrical power to at least one of the sensor unit, the signal processing unit, or the wireless communication unit.

Description

Flexible and lightweight transdermal oxygen partial pressure sensor capable of wireless long-distance communication

The present invention relates to a lightweight transdermal oxygen partial pressure sensor capable of wireless long-distance communication. It relates to a lightweight transdermal oxygen partial pressure sensor capable of communication.

In the conventional oxygen sensor, a sensor unit, a voltage supply unit, and other additional devices are connected by wire. Since such an oxygen sensor needs to monitor a wearer suffering from a chronic disease in real time and respond in a timely manner, connection with a medical support service is essential.

However, since the voltage supply unit and other additional devices are generally very bulky and heavy, the range in which the wearer can move while wearing the oxygen sensor is limited, so there is a problem of poor usability.

In addition, the movement of the wearer is narrowly restricted due to the plurality of wires connected to each positive electrode of the elements constituting the sensor platform, i.e., light source, detector, heater, and remote sensing device, and tension is applied to the sensor by the wearer's movement, resulting in sensing accuracy There was a problem with falling. In addition, poor contact between the device and the electrode may occur due to the movement of the wearer, which has a problem of causing shortening of the lifespan of the sensor.

In addition, although the transdermal oxygen partial pressure sensor itself is flexible and can be attached to any part of the body, additional devices for sensor operation, that is, a photoamplifier that removes noise while amplifying a photocurrent or photovoltage value , a data acquisition module that collects measured current or voltage data, and a power source meter that supplies voltage to the device, have a problem in that they cannot be attached to the body due to their large volume and heavy weight. .

To solve this problem, conventionally, the light generated from the conventional sensing film is measured as photocurrent (nA) and photovoltage (mV) values, and the sensitivity to oxygen gas through the change in the intensity of current and voltage through the Stern-Volmer formula A technique has been attempted to introduce a method of calculating . That is, it is a technique to convert the oxygen partial pressure value using the I _o /I and V ₀ /V values, which are the sensitivity to oxygen concentration. . On the other hand, even if modularized on a PCB, the circuit configuration for amplifying an optical signal, which is a current and voltage source, is very complicated, so the problem of increasing the size of the module could not be solved.

The present invention has been devised to solve the above problems, and it is a lightweight transdermal material capable of wireless long-distance communication capable of measuring oxygen partial pressure in contact with a body part, and wirelessly communicating sensing information about oxygen partial pressure for remote monitoring. It relates to an oxygen partial pressure sensor.

In order to solve the above problems, a flexible and lightweight transdermal oxygen partial pressure sensor capable of wireless long-distance communication according to an embodiment of the present invention is in contact with a part of the body on one side, and a sensing signal for the oxygen partial pressure of the body A power supply that is a battery for supplying power to at least one of a sensor unit providing It is characterized by including wealth.

In addition, the sensor unit, a sensing film, one side of which is in direct contact with a part of the body, is located on the opposite side of one side of the oxygen sensing film, and a light emitting unit including a micro-LED (μ-LED), and an organic-photo A diode (Organic-photodiode, OPD) or an inorganic-photodiode (Inorganic-photodiode, IPD) is characterized in that it includes a light receiving unit.

In addition, the signal processing unit includes a constant voltage circuit for applying a reverse bias voltage to the P-N terminals of an organic-photodiode (OPD), a resistor provided in series between the organic-photodiode and the constant voltage circuit, and a voltage across the resistor. and an output circuit unit for outputting sensing information corresponding to the amount of light received by the organic-photodiode based on the .

In addition, the wireless communication unit, Bluetooth communication, Wi-Fi communication, LF communication, RF communication, LTE communication, 5G communication, Zigbee, EnOcean communication, characterized in that the communication by at least one communication method of Wi-SUN communication.

In addition, the organic-photodiode is characterized by including a Triton X structure in the hole transport layer.

The present invention according to the above configuration is flexible and can be easily attached to curved body parts, is small and light in volume, and has high accuracy, reliability and stability because the sensor and all auxiliary devices are integrally formed. A partial pressure sensor may be provided. In addition, by enabling home-based self-diagnosis of hypoxia-related diseases and real-time long-term monitoring of chronic diseases in line with the medical paradigm of the 4th industrial revolution, there is a great effect in improving public health and reducing medical costs.

1 is a preferred exploded perspective view of the present invention.

2 is a preferred cross-sectional view of the present invention.

3 and 4 are preferred configuration diagrams of the present invention.

100: sensor unit

110: light emitting part

111: light emitting part substrate

115: micro-LED

119: optical filter

120: light receiving unit

121: light receiving unit substrate

125: organic-photodiode

130: sensing film

140: oxygen barrier membrane

150: heater unit

151: electrode

160: temperature sensor

170: light shielding film

200: signal processing unit

300: wireless communication unit

310: bluetooth transmitter

400: power supply

410: battery

Since the present invention can have various changes and can have various embodiments, specific embodiments will be illustrated in the drawings and detailed description will be given. However, this is not intended to limit the present invention to a specific embodiment, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

When a component is referred to as being “connected” or “connected” to another component, it may be directly connected or connected to the other component, but it is understood that other components may exist in between. it should be

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, the technical idea of the present invention will be described in more detail with reference to the accompanying drawings.

Since the accompanying drawings are merely examples shown to explain the technical idea of the present invention in more detail, the technical idea of the present invention is not limited to the form of the accompanying drawings.

An object of the present invention is to provide a device that is light, flexible, and has high biocompatibility, and can check the user's biometric information, specifically oxygen partial pressure, in real time not only for the user (patient), but also for the caregiver, nurse, and doctor, etc. will be.

In order to achieve this object, the present invention provides a sensor unit with one side in contact with a part of the body to provide a sensing signal for oxygen partial pressure in the body, a signal processing unit connected to the sensor unit to generate sensing information, and sensing information. It is preferable to include a power supply unit which is a battery for supplying power to at least one of a wireless communication unit for wirelessly transmitting, and a sensor unit, a signal processing unit, and a wireless communication unit.

Here, one side of the sensor unit 100 may be in contact with the skin and a part of an organ, and more preferably, it may be attached to a part of the body to measure the oxygen partial pressure on the attachment surface. FIG. 1 shows that the sensor unit 100 of the present invention is attached to the wrist, and FIG. 2 shows that the sensor unit 100 of the present invention is attached to a finger and flexibly bent.

Also, the battery may be a lithium ion battery and a lithium polymer battery.

In addition, the sensor unit 100, the sensing film 130, one side of which is in direct contact with a part of the body, is located above the opposite side of the sensing film 130, one side of the micro-LED (μ-LED) It is preferable to include the light emitting unit 110 including the 115 , and the light receiving unit 120 including the organic-photodiode (OPD) 125 .

Although the light receiving unit 120 is described as including the organic photodiode 125 in this embodiment, the light receiving unit 120 may also include an inorganic-photodiode (IPD). That is, both the organic-photodiode and the inorganic-photodiode may be applied to the light receiving unit 120 of the transdermal oxygen partial pressure sensor.

Hereinafter, in this embodiment, the light receiving unit 120 will be described based on the organic photodiode 125 .

The sensor unit 100 has to accurately measure the oxygen partial pressure generated in the skin independently of the external environment such as ambient light and oxygen while attached to the skin and organs, and is sufficient to easily attach to the curved part of the skin. When each element has high flexibility, the measured oxygen partial pressure information can have high reliability. In addition, since it is attached to the skin and organs, it must have high biocompatibility.

To this end, specifically, the sensing film 130 is attached to the body such as the skin of the measurement target, and the measurement target may be a human or an animal. The sensing film 130 is for sensing oxygen supplied from the skin, and as it contains a polymer matrix, a phosphor and a scatterer, it is flexible and harmless to the living body, and it is possible to sense oxygen with high sensitivity due to the internal scatterer. The sensing film 130 may be manufactured to a thickness of 10 μm or more and 20 μm or less.

Meanwhile, the organic-photodiode 125 may be embedded in the flexible light receiving unit substrate 121 . Here, the light-receiving unit substrate 121 may be more preferably a flexible polymer substrate, and may have a thickness of 50 μm. The organic-photodiode 125 may be embedded in the light-receiving unit substrate 121 through a solution process. With this configuration, the light receiving unit 120 can be manufactured to be flexible, thin, and light.

In addition, the light receiving unit 120 may include at least one organic photodiode 125 , and preferably, there may be a plurality of organic photodiodes 125 .

The light emitting unit 110, by using the micro-LED 115 as a light source, compared to the conventional light source OLED, the life of the light source is reduced due to the heat of the heater unit 150 and heat due to the operation of the light source. can be prevented The heater unit 150 will be described later.

The light emitting unit 110 may include at least one micro-LED 115 , and preferably a plurality of micro-LEDs 115 may be plural. Also, preferably, a plurality of micro-LEDs 115 may be arranged on the light emitting unit substrate 111 .

The photodetector including the light emitting unit 110 and the light receiving unit 120 converts a current signal that appears differently depending on the concentration of oxygen adsorbed on the sensing film 130 into a voltage signal for remote sensing and amplification. The light emitting unit may irradiate light to the sensing film 130 .

On the other hand, the sensor unit 100 is positioned between the sensing film 130 and one side of the light emitting unit 110 and blocks oxygen from the outside to the light emitting unit 110 and the light receiving unit 120 . 140 and a light shielding film 170 stacked on the other side of the light receiving unit 120 and blocking light incident from the outside may be further included.

On the other hand, the sensor unit is located between the sensing film and the light detection unit, is a heater unit in the form of a transparent thin film that supplies thermal energy to the skin in contact with the sensing film, and may further include a temperature sensor for measuring the surrounding temperature. can

In addition, the heater unit 150 may increase the reliability of the measured value by supplying thermal energy to the skin in contact with the sensing film 130 . More specifically, when the heater unit 150 heats the body, such as the contacted skin, the flow of blood passing under the heated skin is increased, and accordingly, the partial pressure of oxygen diffused toward the sensing film 130 can be smoothly increased. have. Therefore, oxygen partial pressure can be measured in a more reliable measurement range.

In addition, the temperature sensor may be a temperature sensor chip or a thermocouple.

In addition, the signal processing unit includes a constant voltage circuit for applying a reverse bias voltage to the P-N terminals of an organic-photodiode (OPD), a resistor provided in series between the organic-photodiode and the constant voltage circuit, and a voltage across the resistor. It is preferable to include an output circuit unit for outputting sensing information corresponding to the amount of light received by the organic-photodiode based on the .

Here, applying the reverse bias voltage to the P-N terminal means that the voltage applied to the P terminal is lower than the voltage applied to the N terminal. For this reason, when the organic-photodiode does not receive light, it operates like a general diode and no current flows, and when light is received, a reverse direction (N to P direction) current flows in proportion to the amount of incident light.

Meanwhile, the signal processing unit 200 may calculate the output gain by the modified Stern-Volmer equation. The Stern-Volmer equation is an equation between light intensity and oxygen concentration, and is expressed as Equation 1 below.

here,

is the photocurrent intensity (

is the photovoltage intensity in anaerobic conditions),

is the oxygen concentration

When the photocurrent and photovoltage intensity,

is the light extinction constant expressed as the light extinction efficiency ((μmol L ^-1 ) ^-1 ),

is the concentration of oxygen (μmol L ^-1 ).

Conventionally, photocurrent (nA) and voltage (mV) were measured in light generated from a sensing film, and the sensitivity of oxygen gas according to the change in brightness of current and voltage was calculated by Equation 1 (Stern-Volmer equation). However, since this method includes an optical amplifier that amplifies photocurrent and photovoltage and removes noise, a data collection module that collects data, a power source meter that supplies voltage, etc. There was a difficult problem.

In order to solve this problem, according to the present invention, as shown in Equation 2 below, a modified two-site model-based Stern-Volmer equation based on photocurrent and photovoltage, the above-described optical amplifier, data collection module, and power source meter Since it is not necessary to include at least one of them, the configuration of the remote sensing and amplification and voltage supply circuits can be miniaturized, and there is a great effect of reducing the weight.

The parameter definition of Equation 2 is as follows.

,

: luminescence intensities of a probe in the absence and presence of O ₂

,

: voltage detected proportional to

and

, respectively, at the [O ₂ ] indicated in the subscript

[O ₂ ] : O ₂ concentration in system

f ₁ , f ₂ : the fractions of the O ₂ molecules uniformly and nonuniformly in contact with the PtOEP dye molecules

K ¹ _sv and K ² _sv : Stern-Volmer constants when O ₂ molecules uniformly and nonuniformly encounter the PtOEP dye molecules

Meanwhile, the signal processing unit 200 may control the temperature of the heater unit 150 based on an input from a user or a control signal from an external controller.

The oxygen partial pressure sensor has to measure the oxygen partial pressure in contact with the skin, but oxygen is not smoothly generated into the skin because it is blocked by the structure of the barrier-type lipid layer among the stratum corneum, which is the outermost surface of the skin layer. In order to solve this problem, the signal processing unit 200 controls the heater unit 150 so that the heater unit 150 applies heat of about 37°C to 44°C to the skin layer, thereby contacting the oxygen partial pressure sensor. Oxygen is sufficiently generated on the surface of the damaged skin to improve the measurement accuracy.

In addition, since the measured oxygen concentration may vary depending on the temperature of the skin, the measured oxygen concentration may vary depending on the measurement target, since 37° C. to 44° C. may feel hot or if the skin is soft, such as a small child, the temperature may cause injury. The temperature of (150) is divided into sections so that it can be controlled.

Preferably, according to the temperature, it can be divided into a first section of 37°C or more and 40°C or less, a second section of 40°C or more and 42°C or less, and a third section of 42°C or more and 44°C or less, and input from the user or an external controller One of the first to third sections may be selected based on the control signal of .

In addition, the wireless communication unit 300, Bluetooth communication, Wi-Fi communication, LF communication, RF communication, LTE communication, 5G communication, Zigbee, EnOcean communication, it is preferable to communicate in at least one communication method of Wi-SUN communication. In addition, the wireless communication unit 300 may include a transmitter 310 and a receiver 320 for wireless communication.

More preferably, the wireless communication unit 300 may perform Bluetooth communication, and the transmitter may be a Bluetooth transmitter.

Information transmitted from the wireless communication unit 300 through the Bluetooth transmitter 310 is received by the Bluetooth receiver of the external device, and the oxygen partial pressure value is graphically displayed through a display included in or connected to the external device to allow users, guardians and doctors can be provided to

In addition, the organic-photodiode preferably includes a Triton X structure in the hole transport layer.

Here, the Triton X structure is a nonionic surfactant having a hydrophilic polyethylene oxide chain consisting of 26 hydrogens, 16 carbons, and 2 oxygens and an aromatic hydrocarbon lipophilic or hydrophobic group.

Due to this Triton X structure, rapid crystallization and stabilization in the hole transport layer of the organic-photodiode are possible, and the blended donor acceptor interface included in the light absorption layer at the top of the hole transport layer is formed more stably and uniformly, thereby improving the device performance. There is a huge effect that can be improved.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention as claimed in the claims.

Claims

a sensor unit having one side in contact with a part of the body to provide a sensing signal for oxygen partial pressure in the body;

a signal processing unit connected to the sensor unit to generate sensing information;

a wireless communication unit for wirelessly transmitting the sensing information; and

A power supply unit which is a battery for supplying power to at least one of the sensor unit, the signal processing unit, and the wireless communication unit;

A flexible and lightweight transdermal oxygen partial pressure sensor capable of wireless long-distance communication.
The method of claim 1,

The sensor unit,

One side of the sensing film is in direct contact with a part of the body;

a light emitting part located on the opposite surface of one side of the sensing film and including a micro-LED (μ-LED); and

Organic-photodiode (Organic-photodiode, OPD) or inorganic-photodiode (Inorganic-photodiode, IPD) containing a light receiving unit;

A flexible and lightweight transdermal oxygen partial pressure sensor capable of wireless long-distance communication.
3. The method of claim 2,

The signal processing unit,

a constant voltage circuit for applying a reverse bias voltage to the P-N terminals of the organic-photodiode (OPD);

a resistor provided in series between the organic-photodiode and the constant voltage circuit; and

An output circuit unit for outputting sensing information corresponding to an amount of light received by the organic-photodiode based on the voltages at both ends of the resistor;

A flexible and lightweight transdermal oxygen partial pressure sensor capable of wireless long-distance communication.
3. The method of claim 2,

The wireless communication unit,

Communication using at least one communication method among Bluetooth communication, Wi-Fi communication, LF communication, RF communication, LTE communication, 5G communication, Zigbee communication, EnOcean communication, and Wi-SUN communication

A flexible and lightweight transdermal oxygen partial pressure sensor capable of wireless long-distance communication.
3. The method of claim 2,

The organic-photodiode, including a Triton X structure in the hole transport layer

A flexible and lightweight transdermal oxygen partial pressure sensor capable of wireless long-distance communication.