A bacterial discrimination device and method based on volatile detection

Abstract

The application discloses a bacteria identification device and method based on volatile substance detection. The device comprises a high-purity gas cylinder, a flow controller, an air pipe, a volatile substance extraction unit, a detection unit and an industrial computer unit. Firstly, a characteristic library of bacterial volatile substances is established. Specifically, after bacterial standard samples are cultured, the volatile substances released by the bacteria are extracted by the volatile substance extraction unit and enter the detection unit under the driving of high-purity gas to obtain characteristic volatile substances of each kind of bacteria and establish the characteristic library. Then, the volatile substance information of bacteria in a biological sample is obtained by using the same extraction and detection method. Finally, identification is realized by comparing the algorithm with the characteristic library on the industrial computer unit. The application provides a brand-new device and method for bacterial identification, has the advantages of rapidness, high sensitivity and the like and has a good application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sensor, biomedical engineering and medical health, in particular to a bacteria identification device and method based on volatile matter detection. BACKGROUND

[0002] Bacterial infection can cause a variety of diseases, such as common lung and urinary system inflammation. Traditional bacterial identification methods are mainly based on phenotypic tests, including staining, microscopic examination, motility, colony morphology, oxidase test, and differential growth of bacterial strains in different culture media and catalase. In addition, real-time quantitative PCR technology can also be used for bacterial identification by detecting specific genes. However, these methods are very time-consuming, and in addition to bacterial culture, several hours or even more than 24 hours are still required.

[0003] In recent years, matrix-assisted laser desorption ionization time-of-flight mass spectrometry technology has been developed, which can achieve bacterial identification by measuring the exact molecular weight of peptides, small proteins and ribosomes, and can greatly shorten the bacterial identification time. It has gradually been popularized in hospitals. However, in addition to bacterial culture, the entire detection process still takes about 30 minutes. SUMMARY

[0004] The technical problem solved by the present application is that existing bacterial identification technology is time-consuming and cannot provide timely treatment recommendations, delaying the opportunity for treatment.

[0005] The solution of the present application is a bacterial identification device based on volatile matter detection, characterized in that it comprises a high-purity gas cylinder 1, a flow controller 2, an air pipe 3, a volatile matter extraction unit 4, a detection unit 5, and an industrial computer unit 6. The flow controller 2 is connected to the high-purity gas cylinder 1 and the volatile matter extraction unit 4 through the air pipe 3, the other end of the volatile matter extraction unit 4 is connected to the detection unit 5 through the air pipe 3, and the detection unit 5 is connected to the industrial computer unit 6.

[0006] The high-purity gas cylinder 1 is loaded with high-purity nitrogen, high-purity helium or synthetic air, etc. The purity is greater than or equal to 99.999%, which is used for extracting and transmitting bacterial volatile matter.

[0007] The flow controller 2 can be manually adjusted and electrically controlled, and is used for controlling and monitoring the flow rate of the carrier gas.

[0008] The air pipe 3 is composed of a hollow pipe made of polytetrafluoroethylene, stainless steel or glass, which is used for transmitting carrier gas, and has an inner diameter of 1-10 mm and is subjected to heat tracing treatment at 30-100℃ to prevent the adhesion of bacterial volatile matter.

[0009] The volatile matter extraction unit 4 includes headspace extraction, bubble extraction, spray extraction and other devices, and is mainly used for extracting volatile matter released by bacteria in the culture medium.

[0010] The culture medium includes but is not limited to solid medium and liquid medium, and the oxygen and carbon dioxide content in the culture process is determined according to the bacterial requirements.

[0011] The headspace extraction device extracts the volatile matter released by the cells in the culture medium into the headspace by heating and standing, and uses high-purity gas as the carrier gas to pass into the detection unit.

[0012] The bubble extraction device passes high-purity gas into the bottom of the liquid culture medium to form bubbles, and in the process of rising under the action of buoyancy, the substances released by the bacteria in the culture medium can diffuse into the bubbles and then reach the headspace of the culture medium, and finally pass into the detection unit.

[0013] The spray extraction device atomizes the liquid culture medium into small droplets by pressurization or ultrasonic method, increases the liquid-gas contact area, makes the bacterial volatile matter volatilize quickly into the surrounding high-purity gas, and reaches the detection unit under the driving of the high-purity gas.

[0014] The volatile matter extraction unit can be single or combined by multiple extraction devices to realize automatic extraction and sampling.

[0015] The detection unit is a component sensitive to bacterial volatile matter, or a small sensor or sensor array sensitive to bacterial volatile matter, or a spectral or mass spectrometric sensing instrument, or a combination of the above devices with a chromatograph, and the detection instrument can be selected according to the type of bacterial volatile matter released.

[0016] The method and steps for identifying bacteria by using volatile matter detection are as follows:

[0017] ①Establish a characteristic library of bacteria. Select bacterial samples, place them in the volatile matter extraction unit 4 after culture, extract the volatile matter released by the bacteria, and use high-purity gas to pass into the detection unit 5 to obtain the characteristic volatile matter of each bacterium, and establish a characteristic library.

[0018] ②The biological sample to be tested is cultured by the same method, and the volatile matter released by the bacteria is extracted and detected by the same method as in ① to obtain the volatile matter type and concentration information.

[0019] ③In the industrial computer unit 6, compare the bacterial volatile matter information in the biological sample with the characteristic library, and realize identification by algorithm comparison.

[0020] The advantages of the present application compared with the prior art are:

[0021] The detection speed is fast, for example, using a mass spectrometric detection unit, only a few seconds are needed to complete the detection, which greatly shortens the bacterial identification time, can assist doctors in formulating effective treatment plans for patients in time, and improves the treatment effect. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is a bacterial identification device based on volatile detection.

[0023] In the figure, high-purity gas cylinder 1, flow controller 2, ventilation pipeline 3, volatile extraction unit 4, detection unit 5 and industrial computer unit 6. DETAILED DESCRIPTION

[0024] As Figure 1 shown, a bacterial identification device based on volatile detection includes: high-purity gas cylinder 1, flow controller 2, ventilation pipeline 3, volatile extraction unit 4, detection unit 5 and industrial computer unit 6. High-purity gas cylinder 1 is connected to flow controller 2, volatile extraction unit 4, detection unit 5 and industrial computer unit 6 in turn. The flow controller 2 is connected to the high-purity gas cylinder 1 and the volatile extraction unit 4 through the ventilation pipeline 3, the other end of the volatile extraction unit 4 is connected to the detection unit 5 through the ventilation pipeline 3, and the detection unit 5 is connected to the industrial computer unit 6.

[0025] In order to avoid the pollution of bacterial volatile, the high-purity gas cylinder 1 is loaded with high-purity nitrogen, high-purity helium, synthetic air and other high-purity gases with a purity of greater than or equal to 99.999%, which are used to extract and transport bacterial volatile.

[0026] In order to avoid the adhesion of volatile, the ventilation pipeline 3 is subjected to heat treatment at 30-100℃.

[0027] The detection unit 5 includes sensor, mass spectrum, optical spectrum, chromatography and other technical products, among which the mass spectrum is fast and accurate, the sensor is small, cheap and accurate, the optical spectrum is moderate, and the chromatography has good separation and qualitative ability but is slower. In actual use, it can be selected according to the demand and budget.

[0028] The industrial computer is mainly used for loading data acquisition software and database software of the detection unit.

[0029] The method and steps of bacterial identification using volatile detection are as follows:

[0030] ①Establish a characteristic library of bacteria. Select the standard sample of common clinical susceptible bacteria, place it in the volatile extraction unit 4 after cultivation, extract the volatile released by the bacteria, and use high-purity gas to enter the detection unit 5 to obtain the characteristic volatile of each kind of bacteria, and establish a characteristic library.

[0031] ②The biological sample to be tested is cultured by the same method, and the volatile released by the bacteria is extracted and detected by the same method as in ① to obtain the volatile species concentration information.

[0032] ③In the industrial computer unit 6, compare the bacterial volatile information in the biological sample with the characteristic library, and realize identification through algorithm comparison.

[0033] The bacteria culture process can be selected as a bacteria culture or a sterile culture according to the bacteria type, and accordingly, appropriate carbon dioxide, air or oxygen is introduced.

[0034] The characteristic library of the bacteria is established, the discriminant equation of each bacteria is established by discriminant analysis through the characteristic volatile substance of each bacteria, and then the concentration value of the characteristic substance of the bacteria released in the biological sample is brought into the discriminant equation to realize identification.

[0035] Some parts of the specification of the present application are not described in detail, which belongs to the prior art.

[0036] The above is only part of the specific embodiments of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A bacteria identification device based on volatile matter detection, characterized in that: include: A high-purity gas cylinder (1), a flow controller (2), a ventilation line (3), a volatile matter extraction unit (4), a detection unit (5) and an industrial control computer unit (6); the flow controller (2) is connected to the high-purity gas cylinder (1) and the volatile matter extraction unit (4) respectively through the ventilation line (3); the other end of the volatile matter extraction unit (4) is connected to the detection unit (5) through the ventilation line (3); the detection unit (5) is connected to the industrial control computer unit (6); the industrial control computer is mainly used to load the data acquisition software and database software of the detection unit; the high-purity gas cylinder (1) is loaded with high-purity nitrogen, high-purity helium or synthetic air high-purity gas, the purity of which is greater than or equal to 99.999%; The flow controller (2) can monitor and control the gas flow; The ventilation pipe (3) is composed of a combination of polytetrafluoroethylene, stainless steel or glass tube, with an inner diameter of 1-10 mm, and is heat-treated at 30-100°C; The volatile matter extraction unit (4) is used to extract volatiles released by bacteria in the culture medium, and the volatile matter extraction unit (4) includes a headspace extraction device, a bubbling extraction device or a spray extraction device; The headspace extraction device extracts volatile substances released by cells in the culture medium into the headspace by heating and standing; The bubbling extraction device introduces high-purity gas into the bottom of the liquid culture medium to form bubbles, and the substances in the culture medium diffuse into the bubbles and rise to be extracted into the headspace of the culture medium; The spray extraction device atomizes the liquid culture medium into droplets, causing the substances released by the bacteria therein to evaporate into the surrounding high-purity gas, thereby completing the extraction; the detection unit (5) is a component sensitive to bacterial volatiles, or a sensor or sensor array sensitive to bacterial volatiles, or a spectral and mass spectrometric sensing instrument, or a device combining the above components with a chromatograph.

2. The bacterial identification device based on volatile matter detection according to claim 1, characterized in that: The culture medium includes solid culture medium and / or liquid culture medium.

3. The bacterial identification device based on volatile matter detection according to claim 1, characterized in that: The volatile matter extraction unit (4) is composed of a plurality of extraction devices.

4. A bacterial identification method based on volatile detection, characterized in that: Using the device according to any one of claims 1 to 3, the method comprises the following steps: ① Establishing a bacterial feature library: Select bacterial standard samples, culture them, and place them in a volatile extraction unit (4). The volatiles released by the bacteria are extracted and brought into a detection unit (5) using high-purity gas to obtain the characteristic volatiles of each bacterium and establish a feature library; ② The bacteria in the biological sample to be tested are cultured using the same method as the bacterial standard sample in step (1), wherein the volatiles released by the bacteria in the biological sample to be tested are extracted and detected using the same method as in step (1), and the type and concentration information of the volatiles are obtained; ③ In the industrial computer unit (6), the bacterial volatile information in the biological sample is compared with the feature library, and identification is achieved through algorithm comparison.

Images