Absorbance detection photometer

Abstract

The present invention relates to an absorbance detection photometer, which comprises: an absorption mechanism, which comprises an absorption cell and an absorption liquid; the absorption liquid is arranged in the absorption tank and reacts with a to-be-detected sample to obtain to-be-detected sample absorption liquid; the color developing mechanism comprises a reaction tank and a color developing solution; the color developing solution is arranged in the reaction tank and reacts with the to-be-detected sample absorption solution to obtain a to-be-detected sample detection solution; the detection mechanism comprises a first flow cell, a laser, a photoelectric converter and an MCU chip; laser generated by the laser passes through the first flow cell and the introduced to-be-detected sample detection liquid; the photoelectric converter is used for converting the laser into an electric signal and storing the electric signal in the MCU chip as the absorbance of a sample to be detected; the MCU chip is used for pre-storing a standard curve and comparing the absorbance of the sample to be detected with the standard curve to obtain the concentration of a target object; and the temperature control mechanism is used for controlling the temperature of the developing mechanism and the detection mechanism. The absorbance detection photometer provided by the invention has the advantages of short detection process and high efficiency.

Description

Technical Field

[0001] The present invention relates to the field of detection, and particularly to an absorbance detection photometer. Background Art

[0002] An absorbance detection photometer is a detection device that detects the concentration of a substance based on the light absorption characteristics of the substance. Its working principle is as follows: The target substance in the sample to be detected reacts with a specific absorption solution to form a colored compound, resulting in a colored solution; a detection light beam is irradiated onto the colored solution obtained from the above reaction, and a part of the energy of the detection light beam is absorbed by the colored solution, causing the light intensity of the detection light beam to decrease. The degree of this decrease in light intensity is the absorbance. Since there is a certain mapping relationship between the color depth of the colored solution obtained by the reaction of the sample to be detected with the specific absorption solution and the concentration of the sample to be detected, and there is a specific mapping relationship between the color depth of the colored solution and the absorbance, the absorbance detection photometer can calculate the concentration of the sample to be detected by measuring the magnitude of the absorbance.

[0003] When using the existing absorbance detection photometer to detect the concentration of a substance, it generally includes the following steps: Detect the absorbance of a series of standard solutions with known concentrations, and plot a standard curve reflecting the mapping relationship between "absorbance - concentration"; Detect the absorbance of the sample to be detected to obtain the absorbance of the sample to be detected; Finally, query the standard curve reflecting the mapping relationship between "absorbance - concentration" according to the absorbance of the sample to be detected, and the concentration of the target substance in the corresponding sample to be detected can be calculated. However, in the process of each detection using the existing absorbance detection photometer, it is necessary to prepare standard solutions with different concentrations on-site to plot a standard curve reflecting the mapping relationship between "absorbance - concentration", which not only takes a long time and greatly lengthens the detection process; at the same time, due to the small number of samples in the standard curve plotted on-site, the accuracy of this standard curve is low, which will also have a certain impact on the detection accuracy. Summary of the Invention

[0004] Based on this, the object of the present invention is to provide an absorbance detection photometer, which includes an absorption mechanism, a color development mechanism, a detection mechanism, and a temperature control mechanism; the absorption mechanism includes an absorption cell and an absorption liquid; the absorption liquid is arranged in the absorption cell; the absorption liquid reacts with the target substance in the sample to be measured to obtain the sample to be measured absorption liquid; the color development mechanism includes a reaction cell and a color developing liquid; the color developing liquid is arranged in the reaction cell; the color developing liquid reacts with the sample to be measured absorption liquid to obtain the sample to be measured detection liquid; the detection mechanism includes a first flow cell, a laser, a photoelectric converter, and an MCU chip; the sample to be measured detection liquid is introduced into the first flow cell; the laser generates laser light, and the laser light passes through the first flow cell and the sample to be measured detection liquid therein, and is irradiated on the photoelectric converter; the photoelectric converter converts the optical signal of the laser light into an electrical signal and transmits it to the MCU chip for storage as the absorbance of the sample to be measured; a standard curve under this detection condition is pre-stored in the MCU chip, and it compares the absorbance of the sample to be measured with the standard curve to obtain the concentration of the target substance in the sample to be measured; the temperature control mechanism controls the temperature of the color development mechanism and the detection mechanism.

[0005] Compared with the prior art, the absorbance detection photometer of the present invention simplifies the detection steps and improves the detection efficiency by pre-drawing and storing a high-precision standard curve representing "concentration-absorbance" in the MCU chip without redrawing the standard curve on-site during detection; at the same time, the MCU chip and the temperature control mechanism perform constant temperature control on the reaction area to ensure that the reaction conditions of the standard sample when drawing the standard curve and the sample to be measured during detection are the same, ensuring that the standard curve can be applied, and further improving the detection accuracy while ensuring the detection efficiency.

[0006] Further, the MCU chip pre-stores the absorbance of the standard sample; the MCU chip also obtains the concentration of the target substance of the sample to be measured through the standard curve according to the difference between the absorbance of the standard sample and the absorbance of the sample to be measured; wherein, the absorbance of the standard sample is obtained through the following steps: the color development mechanism further includes a standard solution, which undergoes a color development reaction with the color developing liquid in the reaction cell to obtain a standard sample detection liquid after color development; the detection mechanism performs absorbance detection on the standard sample, so that the MCU chip obtains the absorbance of the standard sample corresponding to the standard sample detection liquid.

[0007] Further, the detection mechanism further includes a spectroscope, a second flow cell, and a reference sample photoelectric converter; the spectroscope divides the light beam generated by the laser into a first light beam and a second light beam with equal light intensity, and the first light beam passes through the first flow cell; the standard sample detection liquid is introduced into the second flow cell; the second light beam passes through the second flow cell and the standard sample detection liquid therein; the reference sample photoelectric converter receives the second light beam after passing through the second flow cell, converts it into an electrical signal, and outputs it as the absorbance of the standard sample to the MCU chip.

[0008] Further, the absorption mechanism further includes an absorption liquid storage tank for storing the absorption liquid; the color development mechanism further includes a color development liquid storage tank for storing the color development liquid; the absorption liquid and the color development liquid are automatically injected into the absorption cell and the reaction cell respectively under the control of the MCU chip.

[0009] Further, the processing circuit further includes: a conversion circuit. The electrical signal obtained in the photoelectric converter is a current signal, and the conversion circuit converts the current signal into a voltage signal; an amplification circuit, which amplifies the voltage signal and outputs it to the MCU chip.

[0010] Further, the conversion circuit includes a first operational amplifier, a first resistor, a first capacitor, a second resistor, a third resistor, a second capacitor, and a fourth resistor. The first operational amplifier is provided with an IN- pin, an IN+ pin, a V- pin, a V+ pin, and an Output pin. The IN- pin is connected to the positive output terminal of the photoelectric converter through the first resistor; the IN+ pin is grounded; the V- pin is connected to a -5V power supply and grounded through the first capacitor; the V+ pin is connected to a +5V power supply; the Output pin is the output terminal of the operational amplifier. One end of the second resistor is connected to the IN- pin of the operational amplifier. One end of the third resistor is connected to the other end of the second resistor, and the other end is connected to the Output pin of the first operational amplifier. The second capacitor is connected in parallel with the second resistor. One end of the fourth resistor is connected to the Output pin of the operational amplifier, and the other end is used as the output terminal of the conversion circuit to output a voltage signal.

[0011] Further, the amplifier circuit includes a second operational amplifier, a fifth resistor, a sixth resistor, a third capacitor, a fourth capacitor, a seventh resistor, an eighth resistor, a fifth capacitor, a ninth resistor, and a sixth capacitor. The second operational amplifier is provided with an OUT- pin, an IN+ pin, a GND pin, a V- pin, a V+ pin, a GND pin 5, an NC pin 6, and an NC pin 7; the OUT- pin is connected to the output end of the conversion circuit to obtain a voltage signal; the IN+ pin is grounded through the fifth resistor; the GND pin is grounded; the V- pin is connected to a +5V voltage; the sixth resistor is a variable resistor, the V+ pin is connected to the IN+ pin through the sixth resistor, and at the same time, the V+ pin is grounded through the third capacitor; the GND pin is grounded through the fourth capacitor; the NC pin 6 is connected to the NC pin 7. One end of the seventh resistor is connected to the V+ pin of the second operational amplifier OPA2. One end of the eighth resistor is connected to the other end of the seventh resistor, and the other end of the eighth resistor is connected to the GND pin 5 of the second operational amplifier OPA2. One end of the fifth capacitor is connected to the NC pin 6 of the second operational amplifier, and the other end is connected to the other end of the seventh resistor. One end of the ninth resistor is connected to the NC pin 7 of the second operational amplifier, and the other end serves as the output end of the amplifier circuit to output the amplified voltage signal; at the same time, the other end of this ninth resistor is grounded through the sixth capacitor.

[0012] Further, the detection mechanism further includes a reference sample conversion circuit and a reference sample amplifier circuit; the structure of the reference sample conversion circuit is the same as that of the conversion circuit, and it converts the current signal generated by the reference sample photoelectric converter into a voltage signal; the structure of the reference sample amplifier circuit is the same as that of the amplifier circuit, and outputs the amplified voltage signal to the MCU chip.

[0013] Further, the first flow cell and the second flow cell are liquid waveguide capillary flow cells.

[0014] Further, it further includes a cleaning solution and a cleaning solution storage tank; the cleaning solution is stored in the cleaning solution storage tank; the cleaning solution storage tank is respectively connected to the absorption cell and the reaction cell, and the MCU chip controls the introduction of the cleaning solution into the absorption cell and the reaction cell for cleaning.

[0015] For better understanding and implementation, the present invention will be described in detail below with reference to the accompanying drawings. Description of the Drawings

[0016] Figure 1 It is a module schematic diagram of the absorbance detection photometer according to Embodiment 1 of the present invention;

[0017] Figure 2Schematic diagram of the overall structure of the absorbance detection photometer according to Embodiment 1 of the present invention;

[0018] Figure 3 Circuit diagram of the conversion circuit of the absorbance detection photometer according to Embodiment 1 of the present invention;

[0019] Figure 4 Circuit diagram of the amplifier circuit of the absorbance detection photometer according to Embodiment 1 of the present invention;

[0020] Figure 5 Schematic diagram of the standard curve of the absorbance detection photometer according to Embodiment 1 of the present invention;

[0021] Figure 6 Schematic diagram of the "concentration - absorbance difference" standard curve of the absorbance detection photometer according to Embodiment 2 of the present invention;

[0022] Figure 7 Overall structure diagram of the absorbance detection photometer according to Embodiment 3 of the present invention. Detailed implementation manners

[0023] Aiming at the problems of long detection time and insufficient accuracy of the standard curve in the existing absorbance detection device during the detection process, the present invention pre - draws a standard curve representing "concentration - absorbance" with a large number of standard sample points, and obtains the mapping relationship and calculation formula between absorbance and concentration based on the pre - drawn standard curve. During on - site detection, the high - precision standard curve and the obtained mapping relationship and calculation formula can be directly called, without the need to re - configure multiple standard solutions to re - draw the standard curve, thereby improving the detection efficiency and speed and reducing the required time. Further, in order to ensure that the pre - drawn standard curve can be applied to the environmental conditions at the detection site, the present invention also uses an MCU chip to control the temperature of the environment in the color - development reaction and detection area to be constant, ensuring that it is consistent with the reaction conditions of the standard solution of the pre - drawn standard curve and improving the accuracy of the pre - drawn standard curve.

[0024] Example 1

[0025] Please refer to Figure 1-2 , Figure 1 Module diagram of the absorbance detection photometer according to Embodiment 1 of the present invention, Figure 2Schematic diagram of the overall structure of the absorbance detection photometer according to Embodiment 1 of the present invention. The absorbance detection photometer of the present invention includes an absorption mechanism 10, a color development mechanism 20, a detection mechanism 30, and a temperature control mechanism 40. The absorption mechanism 10 absorbs and fixes the target substance in the sample to be measured in the external air to obtain an absorption solution of the sample to be measured, and introduces the obtained sample solution into the color development mechanism 20 for a color development reaction to obtain a detection solution of the sample to be measured; subsequently, the detection solution of the sample to be measured is introduced into the detection mechanism 30 for absorbance detection to obtain the concentration of the target substance in the sample to be measured.

[0026] Specifically, the absorption mechanism 10 includes an absorption liquid storage tank, a first micro pump, an absorption cell 11, an absorption liquid 12, and an exhaust fan 13. The absorption liquid 12 is initially stored in the absorption liquid storage tank, and the absorption liquid storage tank is connected to the absorption cell 11 through the first micro pump; during detection, the first micro pump pumps the absorption liquid 12 in the absorption liquid storage tank into the absorption cell 11, so that the absorption liquid 12 reacts with the target substance of the sample to be measured. The air outlet end of the exhaust fan 13 extends into the absorption liquid 12 in the absorption cell 11 through a pipeline, and its air inlet end is connected to the external air; the exhaust fan 13 pumps the external air into the absorption cell 11 to react with the absorption liquid 12 for absorption to obtain an absorption solution 14 of the sample to be measured.

[0027] The color development mechanism 20 includes a color development liquid storage tank, a color development liquid 21, a reaction cell 22, and a second micro pump. The color development liquid 21 is initially stored in the color development liquid storage tank, and the color development liquid storage tank and the absorption cell are connected through a pipeline; during detection, the absorption solution of the sample to be measured enters the reaction cell 22 from the absorption cell 11, and the color development liquid 21 enters the reaction cell 22 from the absorption liquid storage tank through the second micro pump. The absorption solution 14 of the sample to be measured and the color development liquid are mixed and undergo a color development reaction in the reaction cell 22, and after the reaction is completed, a detection solution 23 of the sample to be measured is obtained.

[0028] The detection mechanism 30 includes a laser 31, a first flow cell 32, a photoelectric converter 33, and a processing circuit 34. The optical axis of the laser 31 is on the same horizontal line as the center of the first flow cell 32. The first flow cell 32 is a liquid waveguide capillary flow cell. The detection solution of the sample to be measured enters the first flow cell 32 from the liquid inlet of the flow cell 32 and exits from its liquid outlet. The laser generated by the laser 31 enters from the incident end of the first flow cell 32, and after a part of it is absorbed by the detection solution 23 of the sample to be measured in the first flow cell 32, the remaining part exits from the exit end of the first flow cell 32.

[0029] The processing circuit 34 includes a conversion circuit, an amplification circuit, and an MCU chip. The optical-electric converter 33 is provided with a positive output terminal and a negative output terminal. It receives the laser emitted from the first flow cell 32, converts the laser from an optical signal into a current signal and outputs the current signal at the positive output terminal, and its negative output terminal is grounded. The conversion circuit converts the current signal obtained in the optical-electric converter 33 into a voltage signal. The amplification circuit amplifies the voltage signal to improve the detection accuracy. The MCU chip pre-stores a standard curve representing "concentration - absorbance". At the same time, it stores the voltage signal and performs a comparison calculation with the standard curve to obtain the concentration of the target substance in the sample to be measured. In addition, the MCU chip is also electrically connected to and controls the first microfluidic pump, the second microfluidic pump, the exhaust fan, and the laser.

[0030] Please refer to Figure 3 , Figure 3 which is the circuit diagram of the conversion circuit of the absorbance detection photometer according to Embodiment 1. The conversion circuit includes a first operational amplifier OPA1, a first resistor R1, a first capacitor C1, a second resistor R2, a third resistor R3, a second capacitor C2, and a fourth resistor R4. The model of the first operational amplifier OPA1 is OP-07DPSR, and it is provided with an IN- pin 2, an IN+ pin 3, a V- pin 4, a V+ pin 7, and an Output pin 6. The IN- pin 2 is connected to the positive output terminal of the optical-electric converter through the first resistor R1; the IN+ pin 3 is grounded; the V- pin 4 is connected to a -5V power supply and grounded through the first capacitor C1; the V+ pin 7 is connected to a +5V power supply; the Output pin 6 is the output terminal of the operational amplifier OPA1. One end of the second resistor R2 is connected to the IN- pin 2 of the operational amplifier OPA1. One end of the third resistor R3 is connected to the other end of the second resistor R2, and its other end is connected to the Output pin 6 of the first operational amplifier OPA1. The second capacitor C2 is connected in parallel with the second resistor R2. One end of the fourth resistor R4 is connected to the Output pin 6 of the operational amplifier OPA1, and the other end is used as the output terminal of the conversion circuit to output a voltage signal.

[0031] Please refer to Figure 4 , Figure 4This is the circuit diagram of the amplifier circuit of the absorbance detection photometer according to Embodiment 1. The amplifier circuit includes a second operational amplifier OPA2, a fifth resistor R5, a sixth resistor R6, a third capacitor C3, a fourth capacitor C4, a seventh resistor R7, an eighth resistor R8, a fifth capacitor C5, a ninth resistor R9, and a sixth capacitor C6. The second operational amplifier OPA2 is provided with an OUT- pin 3, an IN+ pin 2, a GND pin 4, a V- pin 8, a V+ pin 1, a GND pin 5, an NC pin 6, and an NC pin 7; the OUT- pin 3 is connected to the output end of the conversion circuit to obtain a voltage signal; the IN+ pin 2 is grounded through the fifth resistor R5; the GND pin 4 is grounded; the V- pin 8 is connected to a +5V voltage; the sixth resistor R6 is a variable resistor, and the V+ pin 1 is connected to the IN+ pin 2 through the sixth resistor R6. At the same time, the V+ pin 1 is grounded through the third capacitor C3; the GND pin 5 is grounded through the fourth capacitor C4; the NC pin 6 is connected to the NC pin 7. One end of the seventh resistor R7 is connected to the V+ pin 1 of the second operational amplifier OPA2. One end of the eighth resistor R8 is connected to the other end of the seventh resistor R7, and the other end of the eighth resistor R8 is connected to the GND pin 5 of the second operational amplifier OPA2. One end of the fifth capacitor C5 is connected to the NC pin 6 of the second operational amplifier OPA2, and the other end is connected to the other end of the seventh resistor R7. One end of the ninth resistor R9 is connected to the NC pin 7 of the second operational amplifier OPA2, and the other end serves as the output end of the amplifier circuit 36 to output the amplified voltage signal; at the same time, the other end of the ninth resistor R9 is grounded through the sixth capacitor C6.

[0032] The temperature control mechanism 40 performs constant temperature control on the reaction cell 22 and the first flow cell 32 to ensure that the conditions for the reaction of the sample to be measured during detection are the same as the reaction conditions of the standard solution when the standard curve is drawn.

[0033] In this embodiment, taking the detection of air formaldehyde concentration by the phenol reagent as an example, at this time, the sample to be measured is air, the target substance is formaldehyde, the absorption solution 11 is the phenol reagent, the color-developing solution 21 is ammonium ferric sulfate, and the wavelength of the laser 31 is 630 nm.

[0034] Please refer to Figure 5 , Figure 5Schematic diagram of the standard curve of the absorbance detection photometer according to Embodiment 1 of the present invention. Before use, start the photometer. The temperature control mechanism controls the reaction cell 22 and the flow cell 32 at a constant temperature of 20 degrees, and start the laser 31 for preheating. Standard formaldehyde absorption solutions with concentrations of 0 μg / 5 ml, 0.1 μg / 5 ml, 0.2 μg / 5 ml, 0.4 μg / 5 ml, 0.6 μg / 5 ml, 0.8 μg / 5 ml, 1.0 μg / 5 ml, 1.5 μg / 5 ml, and 2.0 μg / 5 ml are respectively prepared and injected into the reaction cell 22, and mixed and colored with the coloring solution 21. The absorbances at different concentrations are obtained through the detection mechanism 30 and the processing circuit 34 as shown in the following table:

[0035] Concentration (ug / 5ml) Absorbance 0 0.05 0.1 0.09 0.2 0.1 0.4 0.15 0.6 0.2 0.8 0.25 1.0 0.3 1.5 0.45 2 0.55

[0036] Draw and save a standard curve representing the "concentration-absorbance" relationship in the MCU chip according to the absorbances at each concentration. The standard curve is divided into multiple linear intervals. The calculation formula for the concentration of the sample to be measured under different light intensities of the standard curve is as follows, where A is the absorbance of the reference sample detected during use:

[0037]

[0038]

[0039] During use, place this photometer in the area to be detected and start the device. Start the temperature control mechanism to control the temperature of the reaction cell 22 and the flow cell 32, and start the laser 31 for preheating. When the reaction cell 22 and the first flow cell 32 are stabilized at the preset temperature, the MCU chip controls the first micro pump to pump the absorbent liquid from the absorbent liquid storage tank into the absorption cell 12; meanwhile, the MCU chip starts the exhaust fan 13 to extract the air in the detection area and introduce it into the absorbent liquid 11 in the absorption cell 12. After introducing air for a certain period of time, the absorbent liquid of the sample to be measured is obtained, the exhaust fan 13 is turned off, and the absorbent liquid 14 of the sample to be measured is transferred to the reaction cell 22; meanwhile, the MCU chip starts the second micro pump to pump the chromogenic solution in the chromogenic solution storage tank into the reaction cell 22, mix it with the absorbent liquid 14 of the sample to be measured, and perform a chromogenic reaction. After the chromogenic reaction in the reaction cell 22 is completed, the detection liquid 23 of the sample to be measured is obtained and introduced into the flow cell 32. The laser generated by the laser 31 passes through the standard sample detection liquid 23 in the flow cell 32, irradiates on the photoelectric converter and is converted into an electric signal, and then is converted into a voltage signal through a conversion circuit and amplified by an amplification circuit, and then stored in the MCU chip. The light intensity is converted into the absorbance of the sample to be measured, compared and calculated with the standard curve, and the concentration of the target substance in the sample to be measured is obtained. In this embodiment, the absorbance is obtained by subtracting the value of the electric signal obtained when the laser passes through the first flow cell 32 without the detection liquid 23 of the sample to be measured and irradiates on the photoelectric converter 33 from the value of the electric signal obtained when the laser passes through the first flow cell 32 with the detection liquid 23 of the sample to be measured and irradiates on the photoelectric converter 33.

[0040] In another embodiment, a standard curve reflecting the relationship between light intensity and concentration can also be drawn and the light intensity can be directly used for concentration calculation.

[0041] Furthermore, in order to improve the detection accuracy, a more accurate and wider detection range standard curve can be drawn by configuring more standard solutions.

[0042] Furthermore, it also includes a cleaning liquid and a cleaning liquid storage tank; the cleaning liquid is stored in the cleaning liquid storage tank; the cleaning liquid storage tank is respectively connected to the absorption cell and the reaction cell, and the MCU chip controls the introduction of the cleaning liquid into the absorption cell 11 and the reaction cell 22 for cleaning.

[0043] Example 2

[0044] Please refer to Figure 6 , Figure 6Schematic diagram of the "concentration - absorbance difference" standard curve of the absorbance detection photometer according to Embodiment 2 of the present invention. The specific structure of this Embodiment 2 is basically the same as that of Embodiment 1, with the only difference being that: the color development mechanism 20 further includes a standard sample storage tank, a standard solution, and a third micro - pump. The standard solution is pre - stored in the standard sample storage tank, and the third micro - pump is connected to the sample storage tank and the reaction cell 22. During detection, the third micro - pump pumps the calibration solution into the reaction cell 22, where it is mixed and undergoes a color development reaction with the color - developing solution 21 to obtain a standard sample detection solution, which is then introduced into the detection mechanism 30 for absorbance detection.

[0045] Before use, similar to Embodiment 1, multiple standard formaldehyde solutions with different concentrations are used to obtain the "concentration - absorbance difference" standard curve representing the relationship between formaldehyde concentration and absorbance difference, which is pre - recorded in the MCU chip. According to the linear relationship, the standard curve is divided into 5 linear regions, and a standard formaldehyde solution with a concentration of 0.6 μg / 5 ml is selected as a reference to obtain the formula for each region as shown in the following table, where X is the absorbance difference:

[0046] Absorbance difference range Absorbance Calculation formula -0.15～-0.11 0.05～0.09 2.5X-0.125 -0.11～-0.1 -0.09～0.1 10X+1.2 -0.1-0.1 0.1～0.3 4X+0.6 0.1～0.25 0.3～0.45 (10X+2) / 3 0.25～0.35 0.45～0.55 5X+0.25

[0047] During use, a standard formaldehyde solution with a concentration of 0.6 μg / 5 ml is prepared, and this photometer is placed in the area to be detected and the device is started; at the same time, the temperature control mechanism is started to control the temperature of the reaction cell 22 and the flow cell 32; the laser 31 is started for pre - heating. Subsequently, the color - developing solution 21 is introduced into the reaction cell 22 through the second micro - pump, and then the standard solution is introduced into the reaction cell 22 through the third micro - pump to undergo a color development reaction with the color - developing solution 21; when the color development is completed, a standard sample detection solution is obtained and introduced into the flow cell 32. After the laser generated by the laser 31 passes through the standard sample detection solution in the flow cell 32, it is irradiated on the processing circuit 34 and converted into a voltage signal, which is then stored in the MCU chip to obtain the absorbance of the standard sample. Subsequently, the detection steps for the sample to be measured in Embodiment 1 are carried out, and the absorbance of the sample to be measured obtained is stored in the MCU chip. Subsequently, the light intensity of the standard sample and the light intensity of the sample to be measured are subtracted to obtain the absorbance difference between the sample to be measured and the standard sample, and based on the "concentration - absorbance difference" standard curve corresponding to the standard sample, this difference is projected onto the standard curve, and the concentration of the target substance in the sample to be measured is calculated according to the corresponding formula.

[0048] Furthermore, the order of detecting the absorbance of the standard sample and the absorbance of the sample to be measured can be changed as needed.

[0049] Example 3

[0050] Please refer to Figure 7 , Figure 7 which is the overall structure diagram of the absorbance detection photometer of Embodiment 3 of the present invention. The structure of this Embodiment 3 is basically the same as that of Embodiment 2, with the only difference being that: the detection mechanism 30 further includes a spectroscope 35, a second flow cell 36, a reference signal photoelectric converter 37, a reference electrical signal conversion circuit, and a reference electrical signal amplification circuit. The spectroscope 35 divides the laser generated by the laser 31 into a first light beam and a second light beam with equal light intensity, where the first light beam passes through the first flow cell 32 to detect the absorbance of the test sample detection solution 23; the optical axis of the second light beam is on the same horizontal line as the central axis of the second flow cell 36. The reference sample detection solution 24 flows in from the water inlet of the second flow cell 36 and flows out from the water outlet; another light beam generated by the spectroscope 35 passes through the second flow cell 36 to detect the absorbance of the reference sample detection solution 24. The structure of the reference electrical signal conversion circuit is the same as that of the conversion circuit, and the structure of the reference electrical signal amplification circuit is the same as that of the amplification circuit.

[0051] During use, the photoelectric converter 33 acquires the light intensity of the first light beam after passing through the reference sample detection solution 24 in the first flow cell 32, and obtains the absorbance of the test sample through the conversion circuit and the amplification circuit and stores it in the MCU chip; the standard sample detection solution is introduced into the second flow cell 36, and the second light beam passes through the second flow cell 36 and the standard sample detection solution therein and then irradiates on the reference sample photoelectric converter 37. The reference sample photoelectric converter 37 converts the light intensity of the second light beam into an electrical signal and stores it in the MCU chip, and calculates the absorbance of the standard sample in the MCU chip. The MCU chip subtracts the absorbance of the standard sample from the absorbance of the test sample to obtain the absorbance difference, and compares and calculates this absorbance difference with the standard curve to obtain the concentration of the target substance in the test sample.

[0052] Compared with the prior art, the absorbance detection photometer of the present invention, through the high-precision standard curve of "concentration - absorbance" pre-drawn and stored in the MCU chip, does not need to re-draw the standard curve on-site during detection, simplifies the detection steps, and improves the detection efficiency; at the same time, the reaction area is controlled at a constant temperature through the MCU chip and the temperature control mechanism to ensure that the reaction conditions of the standard sample when drawing the standard curve and the test sample during detection are consistent, ensuring that the standard curve can be applied, and further improving the detection accuracy while ensuring the detection efficiency.

[0053] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the embodiments of the present application. The singular forms "a", "the", and "said" used in the embodiments of the present application and the claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that unless otherwise stated, "a plurality of" means two or more; the terms "first", "second", "third", etc. are only used for distinction, rather than for describing a specific order or sequence, nor can they be understood as indicating or implying relative importance. The term "and / or" used herein means any or all possible combinations of one or more of the associated listed items. When the above description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. In the description of the present application, for those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0054] The above-described embodiments merely represent several implementation manners of the present invention, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and the present invention is also intended to include these modifications and improvements.

Claims

1. An absorbance detection photometer, characterized in that: It includes an absorption mechanism, a color development mechanism, a detection mechanism, and a temperature control mechanism; The absorption mechanism includes an absorption cell and an absorption liquid; the absorption liquid is arranged in the absorption cell; the absorption liquid reacts with the target substance in the sample to be measured to obtain an absorption liquid of the sample to be measured; The color development mechanism includes a reaction cell and a color development liquid; the color development liquid is arranged in the reaction cell; the color development liquid reacts with the absorption liquid of the sample to be measured to obtain a detection liquid of the sample to be measured; The detection mechanism includes a first flow cell, a laser, a photoelectric converter, and an MCU chip; The detection liquid of the sample to be measured is introduced into the first flow cell; The laser generates laser light, and the laser light passes through the first flow cell and the detection liquid of the sample to be measured therein, and irradiates on the photoelectric converter; The photoelectric converter converts the optical signal of the laser into an electrical signal and transmits it to the MCU chip for storage as the absorbance of the sample to be measured; A standard curve under this detection condition is pre-stored in the MCU chip, and it compares the absorbance of the sample to be measured with the standard curve to obtain the concentration of the target substance in the sample to be measured; The temperature control mechanism controls the temperature of the color development mechanism and the detection mechanism.

2. The absorbance detection photometer according to claim 1, wherein: A standard sample absorbance is pre-stored in the MCU chip; the MCU chip also obtains the concentration of the target substance of the sample to be measured through the standard curve according to the difference between the standard sample absorbance and the absorbance of the sample to be measured; Among them, the standard sample absorbance is obtained through the following steps: the color development mechanism further includes a standard solution, which undergoes a color development reaction with the color development liquid in the reaction cell, and a standard sample detection liquid is obtained after color development; the detection mechanism performs absorbance detection on the standard sample, so that the MCU chip obtains the standard sample absorbance corresponding to the standard sample detection liquid.

3. The absorbance detection photometer according to claim 2, characterized in that: The detection mechanism further includes a spectroscope, a second flow cell, and a reference sample photoelectric converter; The spectroscope divides the light beam generated by the laser into a first light beam and a second light beam with equal light intensity, and the first light beam passes through the first flow cell; The standard sample detection liquid is introduced into the second flow cell; the second light beam passes through the second flow cell and the standard sample detection liquid therein; The reference sample photoelectric converter receives the second light beam after passing through the second flow cell and converts it into an electrical signal as the standard sample absorbance and outputs it to the MCU chip.

4. The absorbance detection photometer according to claim 3, characterized in that: The absorption mechanism further includes an absorption liquid storage tank, which stores the absorption liquid therein; The color development mechanism further includes a color development liquid storage tank, which stores the color development liquid therein; The absorption liquid and the color development liquid are respectively automatically injected into the absorption cell and the reaction cell under the control of the MCU chip.

5. The absorbance detection photometer according to claim 4, wherein: The processing circuit further includes: A conversion circuit, the electrical signal obtained in the photoelectric converter is a current signal, and the conversion circuit converts the current signal into a voltage signal; An amplification circuit, which amplifies the voltage signal and outputs it to the MCU chip.

6. The absorbance detection photometer according to claim 5, wherein: The conversion circuit includes a first operational amplifier, a first resistor, a first capacitor, a second resistor, a third resistor, a second capacitor, and a fourth resistor; the first operational amplifier is provided with an IN- pin, an IN+ pin, a V- pin, a V+ pin, and an Output pin; the IN- pin is connected to the positive output terminal of the optoelectronic converter through the first resistor; the IN+ pin is grounded; the V- pin is connected to a -5V power supply and grounded through the first capacitor; the V+ pin is connected to a +5V power supply; the Output pin is the output terminal of the operational amplifier; one end of the second resistor is connected to the IN- pin of the operational amplifier; one end of the third resistor is connected to the other end of the second resistor, and the other end thereof is connected to the Output pin of the first operational amplifier; the second capacitor is connected in parallel with the second resistor; one end of the fourth resistor is connected to the Output pin of the operational amplifier, and the other end is used as the output terminal of the conversion circuit to output a voltage signal.

7. The absorbance detection photometer according to claim 5, wherein: The amplification circuit includes a second operational amplifier, a fifth resistor, a sixth resistor, a third capacitor, a fourth capacitor, a seventh resistor, an eighth resistor, a fifth capacitor, a ninth resistor, and a sixth capacitor; the second operational amplifier is provided with an OUT- pin, an IN+ pin, a GND pin, a V- pin, a V+ pin, a GND pin 5, an NC pin 6, and an NC pin 7; the OUT- pin is connected to the output terminal of the conversion circuit to obtain a voltage signal; the IN+ pin is grounded through the fifth resistor; the GND pin is grounded; the V- pin is connected to a +5V voltage; the sixth resistor is a variable resistor, and the V+ pin is connected to the IN+ pin through the sixth resistor. At the same time, the V+ pin is grounded through the third capacitor; the GND pin is grounded through the fourth capacitor; the NC pin 6 is connected to the NC pin 7; one end of the seventh resistor is connected to the V+ pin of the second operational amplifier OPA2; one end of the eighth resistor is connected to the other end of the seventh resistor, and the other end of the eighth resistor is connected to the GND pin 5 of the second operational amplifier OPA2; one end of the fifth capacitor is connected to the NC pin 6 of the second operational amplifier, and the other end is connected to the other end of the seventh resistor; one end of the ninth resistor is connected to the NC pin 7 of the second operational amplifier, and the other end is used as the output terminal of the amplification circuit to output an amplified voltage signal; at the same time, the other end of the ninth resistor is grounded through the sixth capacitor.

8. The absorbance detection photometer according to claim 7, characterized in that: The detection mechanism further includes a reference sample conversion circuit and a reference sample amplification circuit; The structure of the reference sample conversion circuit is the same as that of the conversion circuit, and it converts the current signal generated by the reference sample optoelectronic converter into a voltage signal; The structure of the reference sample amplification circuit is the same as that of the amplification circuit, and it outputs the amplified voltage signal to the MCU chip.

9. The absorbance detection photometer according to claim 8, wherein: The first flow cell and the second flow cell are liquid waveguide capillary flow cells.

10. The absorbance detection photometer according to claim 1, characterized in that: It also includes a cleaning liquid and a cleaning liquid storage tank; the cleaning liquid is stored in the cleaning liquid storage tank; the cleaning liquid storage tank is respectively connected to the absorption cell and the reaction cell, and the MCU chip controls the introduction of the cleaning liquid into the absorption cell and the reaction cell for cleaning.

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