KR20210021499A - Detection method and detection pad - Google Patents

Abstract

According to an embodiment of the present invention, a detection pad inspects a target in a fluid. The detection pad includes: a machine readable code displayed with a first reference color; a second reference color area used to remove the effect of discoloration due to a fluid; and a detection area including a reagent of which a color is changed in reaction with the target.

Description

Detection method and detection pad {DETECTION METHOD AND DETECTION PAD}

The present technology relates to a detection method and a detection pad.

Body abnormalities of humans and animals can be identified with high accuracy by detecting the concentration of substances contained in body fluids in the living body. An example of detecting body fluid components is a urine test. When the subject provides urine to the patch containing the indicator, the color changes due to the reaction between the components in the urine and the indicator. The changed color is compared with the reference color in the colorimetric table to detect the presence and/or concentration of the component. Another example is the commonly used pregnancy test. During pregnancy, human chorionic gonadotropin (hCG) is excreted in the urine, and the pregnancy tester has a receptor that directly binds to the chorionic gonadotropin, so that it combines with the chorionic gonadotropin to display a predetermined shape and color. do.

Since the color displayed by the pad for detecting the target changes according to the density of the target, the colorimetric table displays various colors according to the target density. However, there are many cases in which the color formed by providing the body fluid to the indicator and the color of the colorimetric table do not correspond accurately, and the color may be misrecognized according to the surrounding environment, so accurate detection may be difficult. Furthermore, it is difficult for the subject to immediately grasp the past history and changes in the present compared to the past because the examination is only one-time.

The present embodiments are one of the problems to be solved to provide a device capable of detecting the presence and/or concentration of a target material easily.

The detection pad according to the present embodiment is a detection pad that inspects a target in a fluid, and the detection pad is: displayed in a first reference color, and a machine readable code, A second reference color region used to remove the effect of discoloration by the fluid and a reagent whose color changes in response to the target include a detection region.

According to the present embodiment, it is possible to quantitatively detect a target in a bodily fluid without using a colorimetric table, and it is possible to convert this into data to store a past history or the like.

1 is an example of a detection pad according to this embodiment.
2 is a flow chart showing an outline of a detection method according to the present embodiment.
3 is a diagram showing a state in which a detection pad according to the present embodiment is photographed by a portable terminal.
4 is a diagram illustrating a photographing result converted to a monochrome tone.
5 is a diagram illustrating a method of detecting a first reagent patch and a fourth reagent patch.
6(A) and 6(B) are diagrams schematically showing a part of a detection pad in order to explain a process of obtaining a gradation value by an application.
Figure 7(a) is a result of measuring the concentration of protein (mg/ml) and standard gradation value in urine, and Fig. 7(b) is the concentration of protein (mg/ml) and standard gradation value in urine It is a diagram of the result of curve fitting for the relationship with
Figure 8(a) is a result of measuring the concentration (pH) of hydrogen ions in urine and the standard gradation value, and Fig. 8(b) shows the relationship between the concentration (pH) of hydrogen ions in urine and the standard gradation value. It is a diagram of the result of curve fitting for the relationship.
Fig. 9(a) is a result of measuring the concentration (mg/ml) of glucose contained in urine and a standard gradation value, and Fig. 9(b) is a result of measuring the concentration (mg/ml) of glucose contained in urine and a standard gradation value It is a diagram of the result of curve fitting for the relationship with
Fig. 10(a) is a result of measuring the occult blood (RBC/ul) and standard grayscale values contained in urine, and Fig. 10(b) shows the relationship between the occult blood (RBC/ul) and standard grayscale values. This is a diagram of the result of curve fitting.
11 is a diagram illustrating a deviation according to the type of a portable terminal that performs photographing.

Hereinafter, an embodiment of a detection pad according to the present embodiment will be described with reference to the accompanying drawings. 1 is an embodiment of a detection pad 10 according to this embodiment. 2 is a flow chart showing an outline of a detection method according to the present embodiment.

In the embodiment illustrated in FIG. 1, the first reference color region displayed as the first reference color may be any one or more of the QR code 110 displayed as the first reference color and the predetermined region 120 displayed as the first reference color. have. In one embodiment, the QR code 110 may be displayed in a square shape. The QR code 110 may include direction markers 112, 114, and 116 positioned at three vertices of a square. The QR code 110 may display the classification of the detection pad 10, the detection target of the detection pad, and the number of reagent patches included in the detection area 300.

The area 120 indicated by the first reference color may be an area in a predetermined area indicated by the first reference color on the substrate sub, and according to another embodiment not shown, the first reference color area is a first reference color. It may include letters, numbers, etc. indicated by, and may further include a pattern. In one embodiment, the first reference color may be black.

In one embodiment, the detection pad 10 may be formed on the substrate sub. For example, the substrate may be a white paper, and the QR code 110 and/or the first reference color region 120 may be formed by printing on the substrate sub.

As will be described later, the second reference color region 200 is used to remove coloration by a fluid including an environment, lighting, and a target during shooting, and may be formed as a second reference color. have. In an embodiment, when the substrate sub is white, a predetermined area of the substrate sub may be the second reference color area 200. In another embodiment, the second reference color region 200 may be attached to a predetermined region of the substrate sub as a white patch through which the color of the fluid may permeate. In yet another embodiment, the second reference color region 200 may be printed on a predetermined region of the substrate sub with white ink that may permeate the color of the fluid. In an embodiment, the second reference color may be white.

The detection area 300 may include one or more reagent patches, and the reagent patches include reagents whose color changes by reacting with a target contained in a fluid. In an embodiment, the reagent reacts with the target in the fluid to vary the degree of color development according to the concentration of the target. For example, reagents are colored according to glucose in fluid, protein in fluid, hydrogen ions in fluid, occult blood in fluid, bilirubin in fluid, urobilinogen in fluid, ketone body in fluid, nitrite in fluid, specific gravity of fluid, and leukocytes in fluid. This can be a changing reagent. For example, the fluid is a human or animal body fluid, and may be any one of blood, urine, saliva, and sweat.

In the embodiment illustrated in FIG. 1, the detection region 300 may include four reagent patches 312, 314, 316, 318, which are glucose in urine, protein in urine, hydrogen ions in urine, or urine. The degree of discoloration can vary depending on the concentration of occult blood in the inside.

In an embodiment not shown, the detection region may include ten reagent patches, each of which is glucose in urine, protein in urine, hydrogen ions in urine, occult blood in urine, bilirubin in urine, urobilinogen in urine, in urine. The degree of discoloration can vary depending on the ketone body, nitrite in urine, the specific gravity of urine, or the concentration of white blood cells in the urine.

Hereinafter, a detection method using the detection pad 10 according to the present embodiment will be described. 3 is a diagram showing a state in which the detection pad 10 according to the present embodiment is photographed by a portable terminal. Referring to FIG. 3, a user photographs a first reference color area displayed as a first reference color using the mobile terminal 20, a second reference color patch, and a detection area whose color changes in response to the target (S100). do. In one embodiment, the user's portable terminal 20 may be a smart phone as shown in FIG. 3 having a camera module, and in another embodiment not shown, the portable terminal is any one of a mobile phone, a tablet, and a laptop. Can be

The user may take a picture of the detection pad 10 using a camera provided in the portable terminal 20 and an application stored in the portable terminal 20. As an example, when taking a picture, the application may show a frame F corresponding to a square of the QR code 110 and a guide mark N that helps the user to take a picture.

The application converts the photographing result into a single factor (S200). In one embodiment, the image captured by the user may be displayed as an R value, a G value, and a B value in an RGB color space, and a single element may be any one of an R value, G value, and B value in the RGB color space. have. If a single element is the R value, the application converts the image captured by the user to the size of the R value only.

A single element can be a linear combination of R, G, and B values. As an example, if the R value, G value, and B value of a pixel included in the image captured by the user are respectively r, g, and b, the single element f is f = α×r + β×g + γ×b. It may be a value expressed as a value, and the application converts the image captured by the user into a size of α×r + β×g + γ×b value.

In another embodiment, a single element may be a grayscale value. The application may convert and display an image captured by the user into grayscale. For example, the grayscale may be divided into a total of 256 levels of 0-255.

In another embodiment, the single element may be any one of a Hue (color), Saturation (saturation), Value (brightness) value, and a linear combination of a Hue value, a Satuaration value, and a Value value in the HSV color space. HSV is a color coordinate system that expresses colors as Hue, Saturation, and Value. Each pixel of the image captured by the user can be displayed as Hue, Saturation, and Value in the HSV color coordinate system, and the application uses any one of the Hue value, Saturation value and Value value, and a linear combination of these values as a single element. And, the image captured by the user can be converted with a single element.

In another embodiment, the single element may be any one of a linear combination of a Cyan (cyan) value, a Magenta (magenta) value, a Yelllow (yellow) value, and a Key value in the CMYK color space. The result image captured by the user can be displayed as Cyan value, Magenta value, Yelllow value, and Key value, and the application uses the Cyan value, Magenta value, Yelllow value, Key value, and a linear combination of these values. Any one of them can be used as a single element, and an image captured by the user can be converted into a single element.

In another embodiment, the single element may be a linear combination of L* values, a* values and b* values and L* values, a* values, and b* values in the CIE Lab color space. The CIE Lab color space is L* with values from black (0) to white (100), a* values with (-) values in green and (+) values in red, and a* values with (-) values in blue and yellow. It is a color coordinate system that displays colors as b* values having a (+) value in. The application uses any one of a linear combination of L* value, a* value and b* value and L* value, a* value, and b* value as a single element, and the image captured by the user. Can be expressed as the size of a single element.

In the above-described embodiment, in the case of calculating a single element with a linear combination of each element, the constants α, β, and γ can be appropriately adjusted according to the range of the values of the calculated elements. As an example, when a value of a single element has a value of 0 to 255 and all r, g, and b values have a value of 0 to 255, all of the constants α, β, and γ may have values of 0 to 1.

The embodiment illustrated in FIG. 4 is a diagram illustrating a photographing result converted into a single element. However, FIG. 4 is a diagram illustrating grayscale as a single element for explanation, and a state converted to grayscale may not be displayed to the user. As illustrated in FIG. 2, images of the first to fourth reagent patches 312, 314, 316, 318 included in the detection area 300 are also converted into a single element.

A single element gradation value is extracted from the photographing result converted into a single element (S300). In an embodiment, the application may detect the position of the detection area 300 before extracting a single element grayscale value. Referring to Figure 5, the application forms a center point (O) between the two direction markers (112, 116) located in the diagonal direction of the QR code 110 square. Subsequently, a reference point P is formed at a distance of a predetermined ratio r with respect to the length between the center point O and the direction marker. The position (a) of the first reagent patch 312 included in the detection area 300 may be determined by rotating the reference point based on the center point O by a predetermined first angle θ1.

Subsequently, by rotating the reference point P based on the center point O by a predetermined second angle θ2, the position (b) of the fourth reagent patch 318 included in the detection area 300 may be determined. In addition, the application divides the distance between the position (a) of the first reagent patch 312 and the position (b) of the fourth reagent patch 318 in three equal portions, and the position of the second reagent patch 314 and the third reagent patch ( 316) can be identified.

In one embodiment, the application forms a second reference point at a distance of a predetermined ratio with respect to the length between the center point O and the direction marker, and rotates the second reference point by a predetermined second angle based on the center point O. The location of the second reference color patch included in the detection area 300 may be determined.

In one embodiment, the application determines the gradation value of a single element at a plurality of different points in the first reagent patch 312, the second reagent patch 314, the third reagent patch 316, and the fourth reagent patch 316. Can be extracted. The application extracts gradation values of a single element for a plurality of points in the second reference color region 200, the first reference color region and the first to fourth reagent patches 312, 314, 316, and 318. 6(A) and 6(B) show that the application of a single element in the second reference color region 200, the first reference color region and the first to fourth reagent patches 312, 314, 316, 318 It is a diagram schematically showing a part of the detection pad in order to explain the process of obtaining the gradation value. In the embodiment shown in FIG. 6(A), the application includes the QR code 110 displayed in the first reference color, the first to fourth reagent patches 312, 314, 316, 318, and the second reference color area ( The gray scale value of a single element can be extracted by obtaining a gray scale value of a single element from a plurality of different points of 200), and obtaining an average value of these values. In the embodiment shown in FIG. 6(B), the application includes the QR code 110 displayed in the first reference color, the first to fourth reagent patches 312, 314, 316, 318, and the second reference color area ( The gray scale value of a single element may be obtained by obtaining a gray scale value of a single element from a plurality of different points of 200), and calculating an average value of values excluding the maximum and minimum values among them to extract the gray scale value of the single element.

The application corrects the extracted single element grayscale value to a standard grayscale value (S400). When the detection area 300 is photographed, light reflected from the floor, ceiling, and wall may be color cast to the first to fourth reagent patches 312, 314, 316, 318, and fluorescent lighting and incandescent lighting There may be color casting by artificial lighting of the back.

In addition, when a fluid including a target is applied to the detection region 300, reagent patches may be discolored due to the color of the fluid. For example, when the fluid is urine, the reagent patches may be colored yellow, and when the fluid is blood, the reagent patches may be colored red.

The application photographs the second reference color region and sets the gradation value of the extracted single element to 255, and the application photographs the first reference color region and sets the gradation value of the extracted single element to 0. The gray values of the extracted single elements ^{are scaled in a total of 2 n} steps to convert the gray values of the single elements photographed from the first to fourth reagent patches 312, 314, 316, 318 into a standard gray level value do. In one embodiment, the application may perform a standard gray-scale value conversion using the equation (1), n is 2 8 ?? ⁿ is 1 to 255, and standard gray level value has a total of 256 steps of 0 to 255.

(I _cal : calculated standard gradation value, I _i: gradation value of a single element extracted in the previous step, G ₁ : gradation value of a single element extracted from the first reference color region, G ₂ : in the second reference color region Gradation value of extracted single element, n: natural number)

Table 2 shows the first to fourth reagent patches when the gradation value (G1) of the single element extracted from the first reference color region is 15 and the gradation value (G2) of the single element extracted from the second reference color region is 231. The gradation values (I1, I2, I3, I4) of a single element extracted from the fields 312, 314, 316, 318, and the gradation values (G1, G1) of the single element extracted from the first and second reference color regions An example of converting G2) into standard grayscale values (Ical1, Ical1, Ical1, Ical1, Gcal1, Gcal2) is illustrated. As illustrated in Table 2, it can be seen that the gradation value of the extracted single element has been converted into a standard gradation value of 256 levels of 0 to 255.

Extracted gradation value Standard gradation value G1 15 Gcal1 0 G2 231 Gcal2 255 I1 175 Ical1 183 I2 195 Ical2 212 I3 134 Ical3 152 I4 125 Ical4 135

The above example is an example for displaying standard grayscale values as 8-bit digital data, and as shown in (1) of Equation 2 below, the grayscale value of a single element extracted by setting n to 10 in Equation 1 is 0. It is possible to obtain a standard gray scale value divided into 1024 steps of to 1023. Alternatively, as shown in Equation (2) of Equation 2 below, a standard grayscale value obtained by dividing the extracted grayscale value into 64 steps of 0 to 63 by calculating n in Equation 1 by 6 can be obtained. If the standard grayscale value divided into higher steps is used, a standard grayscale value having a high resolution can be obtained, and if the standard grayscale value divided into lower steps is used, the calculation speed can be improved.

By scaling the gradation value of a single imaged element to a standard gradation value, it is possible to remove the effect of change in gradation value due to color casting by the environment and light source during the photographing process, and discoloration due to color of fluid. The difference according to the difference between the mobile terminal and the camera module performing the photographing can be similarly removed.

The application detects the target density from the standard grayscale value (S500). In an embodiment, the application detects the target density by calculating a density equation for a standard grayscale value.

There may be a measurement deviation for a standard gray scale according to a camera module included in a portable terminal performing photographing and/or an image processing algorithm of the portable terminal. As a method to reduce the measurement deviation of such a portable terminal, there is a method of deriving an equation about the target concentration for the standard concentration measurement value for each terminal, and measuring the concentration using the equation derived for each terminal. I can. As another method, it is possible to reduce the measurement deviation for each model by collecting data for several mobile terminal models and using the average of the collected data.

Equations 3 to 6 described below are results obtained by collecting data on a mobile terminal model of a plurality of domestic and international mobile terminals and averaging the collected data. Figure 7(a) is a result of measuring the concentration of protein (mg/ml) and standard gradation value in urine, and Fig. 7(b) is the concentration of protein (mg/ml) and standard gradation value in urine It is a diagram of the result of curve fitting for the relationship with In FIG. 7, the horizontal axis represents the standard gray scale indicated by 256 levels, and the vertical axis represents the concentration of protein (mg/ml) in urine. The relationship between the target concentration obtained through the experiment and the standard grayscale value can be obtained through the curve fitting process, and a curve fitting for the relationship between the protein concentration (mg/ml) in urine and the standard grayscale value The resulting equation is shown in Equation 3 below.

(protein: protein concentration, Ical: standard grayscale value, A, B: constant determined by experiment)

Figure 8(a) is a result of measuring the concentration (pH) of hydrogen ions in urine and the standard gradation value, and Fig. 8(b) shows the relationship between the concentration (pH) of hydrogen ions in urine and the standard gradation value. It is a diagram of the result of curve fitting for the relationship. In Fig. 8, the horizontal axis represents the standard gray scale expressed in 256 steps, and the vertical axis represents the hydrogen ion concentration (pH). The relationship between the target concentration obtained through the experiment and the standard grayscale value can be obtained through the curve fitting process, and the result of a linear fitting for the relationship between the concentration (pH) of hydrogen ions in urine and the standard grayscale value The equation is shown in Equation 4 below.

(C, D, E, F, G, H: constants determined by experiment)

Fig. 9(a) is a result of measuring the concentration (mg/ml) of glucose contained in urine and a standard gradation value, and Fig. 9(b) is a result of measuring the concentration (mg/ml) of glucose contained in urine and a standard gradation value It is a diagram of the result of curve fitting for the relationship with In FIG. 9, the horizontal axis represents the standard gray scale indicated by 256 steps, and the vertical axis represents the concentration of glucose (mg/ml). The relationship between the target concentration obtained through the experiment and the standard grayscale value can be obtained through the curve fitting process, and a curve fitting for the relationship between the concentration of glucose in urine (mg/ml) and the standard grayscale value The resulting equation is shown in Equation 5 below.

(I, J: constant determined by experiment)

Fig. 10(a) is a result of measuring the occult blood (RBC/ul) and standard grayscale values contained in urine, and Fig. 10(b) shows the relationship between the occult blood (RBC/ul) and standard grayscale values. This is a diagram of the result of curve fitting. In FIG. 10, the horizontal axis represents the standard gray scale indicated by 256 steps, and the vertical axis represents occult blood (RBC/ul). Through the curve fitting process, the relationship between the target concentration obtained through the experiment and the standard grayscale value can be obtained, and the linear fitting result equation for the relationship between the occult blood (RBC/ul) contained in urine and the standard grayscale value is It is as shown in Equation 6 below.

In another embodiment of detecting the concentration of the target, the application may store the concentration value of the target with respect to the standard grayscale values. The application can detect the density value of the target stored as the calculated standard gray scale value. In an embodiment, the application may interpolate or extrapolate a concentration value of a target stored as a standard grayscale value, and calculate the result of the operation as the concentration value of the target.

Although it has been described with reference to the embodiments shown in the drawings in order to help understanding of the present invention, this is an embodiment for implementation and is only illustrative, and various modifications and equivalent It will be appreciated that other embodiments are possible. Accordingly, the true technical scope of the present invention should be determined by the appended claims.

10: detection pad sub: substrate
20: mobile terminal 110: QR code
112, 114, 116: direction marker 120: area marked with the first reference color
200: second reference color area 300: detection area
312, 314, 316, 318: first, second, third, fourth reagent patch
N: Guide display F: Frame
S100~S500: Each step of the detection method

Claims (8)

A detection pad for testing a target in a fluid, the detection pad comprising:
A machine readable code displayed in a first reference color;
A second reference color region used to remove the effect of discoloration by the fluid, and
A detection pad in which a reagent whose color is changed by reacting with the target includes a detection area. The method of claim 1,
The first reference color is black and the second reference color is white. The method of claim 1,
The machine-readable code is:
A detection pad displaying information about the number of reagent pads included in the detection pad and information about classification of the detection pad. The method of claim 1,
The fluid is a body fluid of any one of human and animal detection pad. The method of claim 1,
The detection area includes a plurality of reagent patches. The method of claim 1,
Each of the plurality of reagent patches includes glucose in the fluid, protein in the fluid, hydrogen ions in the fluid, occult blood in the fluid, bilirubin in the fluid, urobilinogen in the fluid, ketone bodies in the fluid, nitrite in the fluid. And a reagent whose color changes according to specific gravity of the fluid and white blood cells in the fluid. The method of claim 1,
The detection area includes a first reagent patch, a second reagent patch, a third reagent patch, and a fourth reagent patch. The method of claim 7,
Each of the first reagent patch, the second reagent patch, the third reagent patch, and the fourth reagent patch includes glucose in the fluid, protein in the fluid, hydrogen ions in the fluid, occult blood in the fluid, and bilirubin in the fluid. And a reagent whose color changes according to specific gravity of the fluid and leukocytes in the fluid, a urobilinogen in the fluid, a ketone body in the fluid, a nitrite in the fluid, and a white blood cell in the fluid.

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