Method for automatically dispensing and adding digestive solution to microbial sample

Abstract

The application discloses a kind of microbial sample automatic proportioning and filling digestive fluid method, using special filling system, it includes bar code scanner, weighing module, sample module, sample abnormal discharge module and computer, bar code scanner is scanned and sent to computer to sample cup sample code;Weighing module sends the weighing result to the computer;Computer judges sample cup is first sample or second sample according to the code scanning result;According to the weighing result, the weight of sample in sample cup is calculated, controls sample module and injects the digestive fluid in sample cup, and whether opening sample abnormal discharge module is judged according to the weighing result.The application utilizes weighing sensor to weigh sample, according to the method of specific proportioning, injects digestive fluid, reduces the hole block rate, improves positive bacteria detection rate, avoids digestive fluid overflow;Through automatic compensation to inject digestive fluid, make up the error of weighing sensor itself, or the error caused by inaccurate injection digestive fluid flow.

Description

Technical Field

[0001] This invention relates to an automated method for dispensing and mixing microbial samples, and more particularly to a method for automated dispensing and mixing digestive fluids into microbial samples. Background Technology

[0002] Microbiological samples include sputum, urine, blood, cerebrospinal fluid, feces, swabs, pleural effusion, peritoneal effusion, bronchoalveolar lavage fluid, pleural effusion, ascites, and drainage fluid. Because microbial samples are heterogeneous and the bacterial distribution within them is uneven, it is often necessary to add an equal volume of digestive fluid to the sample cup before inoculation. The cup is then shaken and mixed to thoroughly dilute the microbial sample, transforming it into a more homogeneous liquid sample. This facilitates subsequent sampling, streaking, and bacterial culture.

[0003] Currently, the most common clinical method for adding digestive fluid to samples is manual. This method is cumbersome and complex, requiring the microbial sample to be weighed using a balance in a biosafety cabinet, followed by the injection of an equal volume of digestive fluid using a syringe. Due to human error, the amount of digestive fluid added is inaccurate, affecting experimental data; at the same time, the aseptic environment is difficult to control, easily leading to biosafety incidents; and the manual method has low throughput, which cannot meet the testing needs of clinical practice.

[0004] The technical solutions disclosed in Chinese patent announcements CN212159285U ("Automatic Sputum Digestive Fluid Dispensing System") and CN206531717U ("Automatic Sputum Digestive Fluid Dispensing System") both describe the hardware components of the system and its working process. However, both of these methods of dispensing digestive fluid involve dispensing an equal volume of digestive fluid and using a sample dispensing tip (TIP) to draw the sample. This results in a high pore blockage rate and a low positive bacteria detection rate, affecting the interpretation of clinical results. In particular, when adding an equal volume of digestive fluid to samples smaller than 1g, the sample cannot be sufficiently diluted, leading to a high pore blockage rate and requiring manual intervention or inoculation. For large sample volumes, especially those greater than 15g, no sample assessment is performed. Due to the limited volume of the sample cup, adding an equal volume of digestive fluid carries the risk of overflow, posing a biosafety hazard. Furthermore, samples exhibiting abnormalities cannot be reused, impacting testing efficiency. Summary of the Invention

[0005] The purpose of this invention is to provide a method for automatically preparing and adding digestive solution to microbial samples, which greatly reduces the pore blockage rate, improves the detection rate of positive bacteria, and avoids the risk of overflow caused by adding a large amount of digestive solution to a large sample volume.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: The method for automatically preparing and dispensing digestive fluid for microbial samples according to the present invention employs the following dedicated dispensing system: A barcode scanner is used to scan the barcodes on sample cups containing microbial samples and send the scanning results to a computer. A weighing module is used to weigh the sample cup and send the weighing result to the computer; The sample dispensing module is used to inject digestive fluid into the sample cup; The abnormal sample rejection module is used to output abnormal sample cups, which can be manually processed and re-injected. The computer determines whether the sample cup is for the first or second sample injection based on the scanning result; calculates the sample weight in the sample cup based on the weighing result, controls the sample dispensing module to inject the digestive fluid into the sample cup, and determines whether to activate the abnormal sample discharge module based on the weighing result. The addition of digestive fluids includes the following steps: Step 1: The barcode scanner scans the sample cup being injected and sends the scanning result to the computer to determine whether the sample cup is being injected for the first time or a second time. If it is the first time, the sample cup is weighed by the weighing module, and the weighing result is sent to the computer to obtain the sample weight W after deducting the weight of the sample cup itself. The sample weight W is calculated as follows: The actual weight measured by the weighing module is W3. The weight of the sample cup itself, W4 (weight of the empty sample cup), is known. The sample weight W = W3 - W4. If it is a second injection, skip to step 4; Step 2: The computer-controlled sample addition module adds digestive fluid to the sample cup containing the sample weight W. Step 2.1: If the sample weight W is 0 ≤ W < 0.5g, then add the digestive solution weight W1 = 1 - W to obtain the sample mixture weight W5.1. Step 2.2: If the sample weight W is 0.5g≤W<1g, then add the digestion solution weight W1=1g to obtain the sample mixture weight W5.1; Step 2.3: If the sample weight W is 1g≤W<10g, then the weight of the digestive solution added is W1=W×1.3, and the weight of the sample mixture is W5.1. Step 2.4: If the sample weight is 10g≤W≤15g, the weight of the digestive solution added is W1=W, and the weight of the sample mixture is W5.1. Step 2.5: If the sample weight W > 15g, send the sample cup into the sample abnormal discharge module, and re-inject the sample after manual processing. Step 3: Compensate for the digestion fluid error a on the weight W5.1 of the sample mixture obtained in Step 2.1, Step 2.2, Step 2.3 or Step 2.4, where a = (W + D1 - W5.1) / D1, and D1 is the theoretical amount of digestion fluid to be added. Step 3.1: If a≤20%, the addition of digestion solution is completed, and the sample cup proceeds to the next mixing process; Step 3.2: If a>20%, continue to add digestion solution with a weight of W+D1-W5.1 until the theoretical amount of digestion solution added, D1, is reached. The addition of digestion solution is then completed, and the sample cup enters the next mixing process. Step 4: For the sample cups used for secondary injection, determine whether digestion solution has been added; if digestion solution has been added, compensate for the digestion solution error b by adding digestion solution to the weight W5.2 of the sample mixture in the sample cup, b=(W+D1- W5.2) / D1; Step 4.1: If b≤50%, the addition of digestion solution is completed, and the sample cup proceeds to the next mixing process. Step 4.2: If b > 50%, continue adding digestion solution W + D1 - W5.2 until the theoretical amount of digestion solution D1 is reached. The addition of digestion solution is then completed, and the sample cup proceeds to the next mixing process.

[0007] Optionally, the weighing module includes a microcontroller that is connected to the computer via CAN communication, and the digital signal input terminal of the microcontroller is connected to the signal output terminal of the weighing sensor through an analog-to-digital converter; The sample addition module includes an electric injector driven by a first motor drive board, wherein the control input terminal of the first motor drive board is connected to the control output terminal of a computer. The sample abnormality discharge module includes a conveying channel driven by a second motor drive board, wherein the control input terminal of the second motor drive board is connected to the computer control output terminal; The barcode scanner is a CCD barcode scanner.

[0008] The advantages of this invention are reflected in the following aspects: 1. Samples are weighed using a weighing sensor, and digestion solution is added according to a specific ratio. Clinical trials have shown that this significantly reduces the pore blockage rate, increases the detection rate of positive bacteria, and avoids the risk of overflow caused by adding large amounts of digestion solution to large sample volumes. Automatic compensation for the added digestion solution compensates for errors in the weighing sensor itself or inaccurate flow rates, thereby reducing the pore blockage rate and increasing the detection rate of positive bacteria.

[0009] 2. It supports the function of customizing the amount of digestion solution added. For other types of microbial samples, through a large number of clinical trials, if the proportion of digestion solution added to the sample is not appropriate, the amount of digestion solution added can be controlled by modifying the parameters, which improves the automation and intelligence of digestion solution addition.

[0010] 3. By scanning the barcode affixed to the sample cup, it can be determined whether the sample is being injected for the first time or for the second time. Abnormal samples do not require manual inoculation and can be directly injected after manual processing.

[0011] 4. Abnormal sample cups are automatically discharged, avoiding biosafety issues and improving the detection rate. Attached Figure Description

[0012] Figure 1 This is a flowchart of the automatic dispensing of digestive fluid according to the present invention.

[0013] Figure 2 This is a schematic diagram of the filling system described in this invention. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0015] It should be noted that, in this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixation," etc., should be interpreted broadly. For example, "fixation" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0016] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature.

[0017] Furthermore, the meaning of "and / or" throughout the text is to include three parallel solutions. Taking "A and / or B as an example" as an example, it includes solution A, solution B, or a solution that satisfies both A and B. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0018] like Figure 1 , 2 As shown, the method for automatically preparing and dispensing digestive fluid for microbial samples according to the present invention employs the following dedicated dispensing system: A barcode scanner is used to scan the barcodes on sample cups containing microbial samples and send the scanning results to a computer.

[0019] Preferably or exemplary, the barcode scanner is a CCD barcode scanner, which has excellent scanning performance for all one-dimensional and two-dimensional barcodes, supports RS232 communication, and its simple and compact appearance allows it to be perfectly integrated into the device.

[0020] The weighing module is used to weigh the sample cup and send the weighing result to the computer.

[0021] Preferably or exemplary, such as Figure 2 As shown, the weighing module includes a microcontroller (STM32F103RBT6) that is connected to the computer via CAN communication. The digital signal input terminal of the microcontroller is connected to the signal output terminal of the weighing sensor through an analog-to-digital converter. The microcontroller is a 32-bit microprocessor based on the ARM Cortex-M3 core.

[0022] The load cell is made of aluminum alloy and internally sealed with glue, making it oil-proof, waterproof, and corrosion-resistant. It features a single-point parallel beam structure.

[0023] The sample dispensing module is used to inject digestive fluid into the sample cup.

[0024] Preferably or exemplary, such as Figure 2 As shown, the sample dispensing module includes an electric syringe (10mL) driven by a first motor drive board. The control input terminal of the first motor drive board is connected to the control output terminal of the computer. The main control MCU of the first motor drive board is the STM32F105VCT6 designed by STMicroelectronics, which is a 32-bit microprocessor based on the ARM Cortex-M3 core.

[0025] The sample anomaly rejection module is used to output abnormal sample cups, which can be manually processed and re-injected.

[0026] Preferably or exemplary, such as Figure 2 As shown, the sample abnormal discharge module includes a conveying channel driven by a second motor drive board, and the control input terminal of the second motor drive board is connected to the computer control output terminal.

[0027] The conveying channel can use a conveyor motor controlled by a second motor drive board, which drives a conveyor belt consisting of a drive wheel, a driven wheel, and a belt; of course, other conveying mechanisms can also be used.

[0028] The computer determines whether the sample cup is for the first or second sample injection based on the scanning result; calculates the sample weight in the sample cup based on the weighing result, controls the sample addition module to inject the digestive fluid into the sample cup, and determines whether to activate the abnormal sample discharge module based on the weighing result.

[0029] The digestive fluid injection method of the present invention includes the following steps: Step 1: The barcode scanner scans the sample cup being injected and sends the scanning result to the computer to determine whether the sample cup is being injected for the first time or a second time. If it is the first time, the sample cup is weighed by the weighing module, and the weighing result is sent to the computer to obtain the sample weight W after deducting the weight of the sample cup itself. The sample weight W is calculated as follows: The actual weight measured by the weighing module is W3. The weight of the sample cup itself, W4 (weight of the empty sample cup), is known. The sample weight W = W3 - W4. If it is a second injection, skip to step 4; Step 2: The computer-controlled sample addition module adds digestive fluid to the sample cup containing the sample weight W. Step 2.1: If the sample weight W is 0 ≤ W < 0.5g, then add the digestive solution weight W1 = 1 - W to obtain the sample mixture weight W5.1. Step 2.2: If the sample weight W is 0.5g≤W<1g, then add the digestion solution weight W1=1g to obtain the sample mixture weight W5.1; Step 2.3: If the sample weight W is 1g≤W<10g, then the weight of the digestive solution added is W1=W×1.3, and the weight of the sample mixture is W5.1. Step 2.4: If the sample weight is 10g≤W≤15g, the weight of the digestive solution added is W1=W, and the weight of the sample mixture is W5.1. Step 2.5: If the sample weight W > 15g, send the sample cup into the sample abnormal discharge module, and re-inject the sample after manual processing. Step 3: Compensate for the digestion fluid error a on the weight W5.1 of the sample mixture obtained in Step 2.1, Step 2.2, Step 2.3 or Step 2.4, where a = (W + D1 - W5.1) / D1, and D1 is the theoretical amount of digestion fluid to be added. Step 3.1: If a≤20%, the addition of digestion solution is completed, and the sample cup proceeds to the next mixing process; Step 3.2: If a>20%, add digestion solution with a weight of W+D1-W5.1 in a cycle until the theoretical amount of digestion solution added, D1, is reached. The addition of digestion solution ends and the sample cup enters the next mixing process. Step 4: For the sample cups used for secondary injection, determine whether digestion solution has been added; if digestion solution has been added, compensate for the digestion solution error b by adding digestion solution to the weight W5.2 of the sample mixture in the sample cup, b=(W+D1- W5.2) / D1; Step 4.1: If b≤50%, the addition of digestion solution is completed, and the sample cup proceeds to the next mixing process. Step 4.2: If b > 50%, add digestion solution W + D1 - W5.2 in a cycle until the theoretical amount of digestion solution D1 is reached. The digestion solution addition is then completed, and the sample cup enters the next mixing process.

[0030] The principle behind this invention, which involves adding digestive fluid according to a specific ratio, is as follows: Currently, commercially available automated digestive fluid dispensing equipment does not support small sample volumes, generally referring to samples less than 1g. Clinically, the method of dispensing digestive fluid in equal volumes presents two risks for samples smaller than 1g, especially less than 0.5g: 1. The weighing sensor and the sample cup have inherent errors. These errors accumulate, leading to either too much or too little digestive fluid being dispensed. Insufficient dispensing results in the needle failing to aspirate the sample (empty aspiration). This invention incorporates an automatic digestive fluid dispensing compensation function, reducing the weighing sensor's inherent error and improving the success rate of sample aspiration. 2. The needle diameter is 1mm. For samples smaller than 0.5g, the needle may fail to aspirate the sample, or the aspirated sample may contain air bubbles. To ensure that the sampling needle can aspirate samples after adding digestion solution for small sample volumes without affecting the single colony isolation rate and improving the detection rate of pathogenic bacteria and positive bacteria, it is proposed that if the sample weight is 0 ≤ W < 0.5g, the weight of digestion solution added, W1 = 1 - W; if the sample weight is 0.5g ≤ W < 1g, the weight of digestion solution added, W1 = 1. This ensures safe processing of small sample volumes while mitigating errors. Therefore, this invention supports processing small sample volumes (less than 1g) while avoiding errors caused by weighing sensors and sample cups.

[0031] For large sample volumes exceeding 15g, after adding digestive fluid, the sample is directly sent to the anomaly rejection channel. This is because the maximum capacity of the sample cup is 40g. If the sample is larger than 15g, there is a risk of overflow if the weight exceeds 40g after adding digestive fluid. Since the weighing sensor and sample cup weight have some error, a large sample volume exceeding 15g is rejected to allow for a margin of error. Furthermore, after adding digestive fluid to samples exceeding 15g, mixing is necessary. During mixing, the sample undergoes a chemical reaction, which can produce foam, posing a risk of overflow and creating a biosafety hazard.

[0032] For samples with a volume of 1g ≤ W < 10g, adding 1.3 times the amount of digestion solution is necessary to reduce the pore blockage rate. Since the sample dispensing needle has a relatively small diameter of 1mm, if the sample is not sufficiently diluted and contains impurities, it can easily cause pore blockage. Experimental comparisons show that adding 1.3 times the amount of digestion solution, after thorough mixing, shaking, and chemical dilution, results in a significantly lower pore blockage rate compared to adding 1 times the amount of digestion solution, while not affecting the single colony isolation rate and improving the detection rate of pathogenic bacteria.

Claims

1. A method for automatically preparing and dispensing digestive solution from microbial samples, characterized in that: The following refueling system is used: A barcode scanner is used to scan sample cups containing microbial samples and send the scanning results to a computer. A weighing module is used to weigh the sample cup and send the weighing result to the computer; The sample dispensing module is used to inject digestive fluid into the sample cup; The abnormal sample rejection module is used to output abnormal sample cups, which can be manually processed and re-injected. The computer determines whether the sample cup is for the first or second sample injection based on the scanning result; calculates the sample weight in the sample cup based on the weighing result, controls the sample dispensing module to inject the digestive fluid into the sample cup, and determines whether to activate the abnormal sample discharge module based on the weighing result. The addition of digestive fluids includes the following steps: Step 1: The barcode scanner scans the sample cup to determine whether the sample cup is being injected for the first time or for the second time. If it is the first injection, weigh the sample cup to obtain the sample weight W after deducting the weight of the sample cup itself; if it is the second injection, skip to step 4. Step 2: Add digestive fluid to the sample cup containing the sample weight W: Step 2.1: If the sample weight W is 0 ≤ W < 0.5g, then add the digestive solution weight W1 = 1 - W, and weigh to obtain the sample mixture weight W5.1; Step 2.2: If the sample weight W is 0.5g≤W<1g, then add the digestive solution weight W1=1g, and weigh to obtain the sample mixture weight W5.1; Step 2.3: If the sample weight W is 1g≤W<10g, then the weight of the added digestive solution W1=W×1.3, and the weight of the sample mixture W5.1 is obtained by weighing. Step 2.4: If the sample weight W is 10g≤W≤15g, the weight of the added digestive solution is W1=W, and the weight of the sample mixture is obtained by weighing W5.

1. Step 2.5: If the sample weight is W > 15g, send the sample cup into the sample abnormal discharge module, and re-inject the sample after manual processing. Step 3: Compensate for the digestion error a of the sample mixture weight W5.1 obtained in Step 2.1, Step 2.2, Step 2.3 or Step 2.4, where a = (W + D1 - W5.1) / D1, and D1 = W1, which is the theoretical amount of digestion solution to be added. Step 3.1: If a ≤ 20%, the addition of digestive fluid is complete; Step 3.2: If a > 20%, continue to add digestive fluid with a weight of W + D1 - W5.1 until the theoretical amount of digestive fluid added, D1, is reached, and the addition of digestive fluid ends. Step 4: For sample cups used for secondary injection, determine whether digestion solution has been added; If digestion solution has already been added, the weight of the sample mixture in the sample cup, W5.2, is compensated for the digestion solution error b, where b = (W + D1 - W5.2) / D1; D1 = W1, which is the theoretical amount of digestion solution to be added. Step 4.1: If b ≤ 50%, the addition of digestive fluid is complete; Step 4.2: If b > 50%, continue adding digestive fluid of W + D1 - W5.2 until the theoretical amount of digestive fluid added, D1, is reached, and the addition of digestive fluid ends.

2. The method for automatically preparing and adding digestive solution to microbial samples according to claim 1, characterized in that: The weighing module includes a microcontroller that is connected to the computer via CAN communication. The digital signal input terminal of the microcontroller is connected to the signal output terminal of the weighing sensor through an analog-to-digital converter. The sample addition module includes an electric injector driven by a first motor drive board, wherein the control input terminal of the first motor drive board is connected to the control output terminal of a computer. The sample abnormality discharge module includes a conveying channel driven by a second motor drive board, wherein the control input terminal of the second motor drive board is connected to the computer control output terminal; The barcode scanner is a CCD barcode scanner.

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