An automatic online amino acid derivatization device

Abstract

The utility model relates to an amino acid automatic online pre-column derivatization device, aims at solving the technical problem that manual derivatization operation is complicated, sample exposure process is easy to be polluted by dust, water vapor, microorganism etc. in the environment, leads to the incomplete derivatization reaction or the deviation of detection result, including support frame and elevating cylinder, elevating cylinder sets up the top of sample tray, the surface of sample tray is equipped with a plurality of sample grooves in the form of circular array, the surface of sample tray outside each sample groove is equipped with annular groove, the bottom of elevating cylinder inserts in the inside of annular groove, the top of elevating cylinder is fixedly connected with no. 2 electric push rod, the utility model forms the sealed environment through elevating cylinder descending, then the inside uncapping subassembly and filling subassembly complete the separation of sample bottle top cover and the addition of derivatization reagent automatically, do not need manual intervention throughout, effectively avoid the pollution caused by the frequent exposure of sample to external environment, guarantee sample purity, reduce error, help the accurate and reliable detection result.

Description

Technical Field

[0001] This utility model relates to the field of amino acid detection technology, specifically to an automatic online pre-column derivatization device for amino acids. Background Technology

[0002] Pre-column derivatization of amino acids is a core pretreatment step in amino acid detection technologies such as high performance liquid chromatography (HPLC) and ultra-high performance liquid chromatography (UHPLC). The principle is to react derivatizing reagents with amino acids to generate derivatives with strong ultraviolet absorption or fluorescence activity, thereby achieving accurate qualitative and quantitative determination of amino acids. The completeness, stability, and degree of automation of the derivatization reaction directly determine the accuracy and efficiency of the detection results.

[0003] Traditional manual derivatization is cumbersome, requiring manual step-by-step procedures such as sample collection, reagent addition, mixing and incubation, and sample injection. This is not only time-consuming and labor-intensive, but also susceptible to contamination from environmental dust, moisture, and microorganisms during sample exposure, leading to incomplete derivatization reactions or inaccurate test results. This makes it difficult to meet the demands for efficient and accurate detection of batch samples. Therefore, a new technical solution is proposed to address this issue. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology, adapt to practical needs, and provide an automatic online pre-column derivatization device for amino acids. This device solves the technical problems of cumbersome traditional manual derivatization operations and the susceptibility of samples to contamination by dust, water vapor, microorganisms, etc. in the environment during exposure, which can lead to incomplete derivatization reactions or deviations in detection results.

[0005] To achieve the purpose of this utility model, the technical solution adopted by this utility model is as follows: An automatic online pre-column derivatization device for amino acids is designed, including a support frame and a lifting cylinder. The lifting cylinder is positioned above a sample tray. The surface of the sample tray is arranged in a circumferential array with several sample slots. Each sample slot has an annular groove on its outer surface. The bottom end of the lifting cylinder is inserted into the annular groove. A second electric actuator is fixedly connected to the top end of the lifting cylinder. The bottom end of the second electric actuator is located inside the lifting cylinder and fixedly connected to a capping assembly. A third electric actuator is fixedly connected to the outer wall of the lifting cylinder. The telescopic end of the third electric actuator is located inside the lifting cylinder and fixedly connected to a dispensing assembly.

[0006] In this solution, the lifting cylinder descends and its bottom is inserted into the annular groove, thus forming a sealed environment. Subsequently, the internal capping and dispensing components automatically remove the sample vial cap and add the derivatized reagents. The entire process requires no manual intervention, effectively avoiding contamination caused by frequent exposure of the sample to the external environment, ensuring sample purity, improving the degree of automation, reducing human error, and helping to make the test results accurate and reliable.

[0007] Preferably, the cap removal assembly includes an electric gripper, and hooks are fixedly connected to the two sidewalls of the bottom of the electric gripper.

[0008] In practical applications, the second electric actuator drives the electric gripper to move downwards, closing the gripper so that the hook block catches the sample vial cap. Then, the electric actuator lifts the vial to remove the cap. The hook block firmly grips the cap to prevent it from falling off. After the reagent is added, the vial descends along the same path to reinsert the cap into the sample vial opening. No manual contact is required, avoiding sample contamination. At the same time, automated operation improves capping efficiency and consistency, making it suitable for batch sample processing.

[0009] Preferably, the dispensing assembly includes a fixing frame, a dispensing head is fixedly connected to the surface of the fixing frame, the dispensing head is connected to the reagent box at the top of the support frame through a delivery pipe, and the part of the delivery pipe that passes through the lifting cylinder is sealed.

[0010] In practical applications, the derivatized reagents in the reagent box flow to the dispensing head via the delivery tube. The No. 3 electric actuator pushes the fixing frame, causing the dispensing head to move down above the sample vial for dispensing. The delivery tube is sealed to prevent inert gas leakage and external contamination. The dispensing head position is precisely controllable, ensuring a stable reagent addition and guaranteeing the effectiveness of the derivatization reaction.

[0011] Preferably, a lifting plate is fixedly connected to the upper end of the outer side wall of the lifting cylinder, a sliding rod is fixedly connected to the outer surface of the support frame, the sliding rod passes through the lifting plate and is slidably connected to the lifting plate, and a first electric push rod is fixedly connected between the lifting plate and the outer surface of the support frame.

[0012] In practical applications, the extension and retraction of the No. 1 electric actuator drives the lifting plate to slide up and down along the slide bar, thereby controlling the lifting of the lifting cylinder. The slide bar limits the offset of the lifting plate, ensuring that the lifting cylinder accurately aligns with the annular groove, guaranteeing a sealing effect. The electric actuator provides stable driving force, automating the lifting action and reducing human error.

[0013] Preferably, a gas cylinder is placed inside the cavity of the support frame, and an air inlet pipe is provided between the gas cylinder's nozzle and the lifting cylinder, with both ends of the air inlet pipe connected to the gas cylinder and the lifting cylinder, respectively.

[0014] In practical applications, after the lifting cylinder is sealed, the inert gas in the gas cylinder is transported to the lifting cylinder through the gas inlet pipe, quickly replacing the air in the lifting cylinder, creating a clean and inert environment for the derivation reaction, avoiding sample oxidation, and ensuring the accuracy of the test results.

[0015] Preferably, an exhaust pipe is provided at the top edge of the lifting cylinder, and a one-way valve is sealed to the surface of the exhaust pipe.

[0016] In practical applications, when the gas cylinder is supplied with gas, the original air in the lifting cylinder is discharged through the exhaust pipe, and the one-way valve prevents external air from entering in reverse. This completely replaces the air inside the cylinder, maintains a stable inert environment, and the one-way valve's sealed connection prevents gas leakage, ensuring that the derivative reaction is not disturbed by external factors and improving process reliability.

[0017] Preferably, the sample trays on both sides of the annular groove are provided with slots, the slots are connected to the sample groove, and a pressing block is slidably connected to the inner side of the slot. An insert block is fixedly connected to the outer wall of the lifting cylinder directly above the slot.

[0018] In practical applications, as the lifting cylinder descends, the insert block enters the slot, pushing the squeezing block towards the sample vial until it is clamped. No additional drive components are needed; the lifting action, combined with clamping, ensures the sample vial remains stable and does not shift during capping and filling, simplifying the device structure and reducing maintenance costs and the risk of malfunction.

[0019] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0020] 1. This utility model features a lifting cylinder positioned directly above the sample tray of the chromatograph. When adding derivatizing reagents to the sample, the lifting cylinder descends and its bottom inserts into the annular groove, creating a sealed environment. Subsequently, the internal cap removal and dispensing components automatically remove the sample vial cap and add the derivatizing reagents. The entire process requires no manual intervention, effectively avoiding contamination caused by frequent exposure of the sample to the external environment, ensuring sample purity, improving the degree of automation, reducing human error, and contributing to accurate and reliable detection results.

[0021] 2. This utility model provides slots and squeezing blocks on both sides of the sample cell. When the bottom of the lifting cylinder is inserted into the annular groove, the outer wall block is simultaneously inserted into the slot and pushes the squeezing block to clamp the sample bottle, ensuring that the sample bottle is stable and does not shift during the capping and filling process. In addition, the lifting cylinder is filled with inert gas, which creates a stable and clean environment for the derivatization reaction, avoids interference from external factors, further ensures the completeness and stability of the derivatization reaction, and improves the repeatability of the detection data. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall design of this utility model;

[0023] Figure 2 This is a schematic diagram of the sample tray structure of this utility model;

[0024] Figure 3 This is a side view of the support frame of this utility model;

[0025] Figure 4 This is a cross-sectional view of the sample well of this utility model;

[0026] Figure 5 This is a schematic diagram of the interior of the lifting cylinder of this utility model;

[0027] Figure 6 This is a partial enlarged view of point A of this utility model;

[0028] In the diagram: 1. Support frame; 2. Slide rod; 3. Electric actuator No. 1; 4. Lifting plate; 5. Lifting cylinder; 501. Insert block; 6. Electric actuator No. 2; 7. Electric gripper; 701. Hook block; 8. Sample tray; 801. Sample groove; 802. Annular groove; 803. Slot; 9. Extrusion block; 10. Exhaust pipe; 1001. One-way valve; 11. Electric actuator No. 3; 12. Fixing frame; 13. Filling head; 131. Delivery pipe; 14. Reagent box; 15. Gas cylinder; 151. Inlet pipe. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0030] Example 1: An automated online pre-column derivatization device for amino acids, see [link to example]. Figures 1 to 6 The system includes a support frame 1 and a lifting cylinder 5. The lifting cylinder 5 is positioned above the sample tray 8, which is capable of rotation driven by a motor at its bottom and is carried by the chromatograph itself. The surface of the sample tray 8 is provided with several sample slots 801 arranged in a circumferential array. Each sample slot 801 has an annular groove 802 on the outer surface of the sample tray 8. The bottom end of the lifting cylinder 5 is inserted into the annular groove 802, and a sealing ring is provided at the bottom of the lifting cylinder 5. A second electric actuator 6 is fixedly connected to the top of the lifting cylinder 5. The bottom end of the second electric actuator 6 is located inside the lifting cylinder 5 and is fixedly connected to the cap removal assembly. A third electric actuator 11 is fixedly connected to the outer wall of the lifting cylinder 5. The telescopic end of the third electric actuator 11 is located inside the lifting cylinder 5 and is fixedly connected to the dispensing assembly. The installation positions of the second electric actuator 6 and the third electric actuator 11 are sealed, for example, by using glue to fill them, thereby ensuring the sealing of the lifting cylinder 5.

[0031] In the above technical solution, after the device is started, the sample tray 8 can be rotated by the bottom motor to transfer the sample vial to be derivatized to the area directly below the lifting cylinder 5. Then, the lifting cylinder 5 descends, its bottom end inserting into the annular groove 802 to quickly form a closed space. The second electric actuator 6 then drives the capping assembly to move down and complete the capping of the sample vial. The third electric actuator 11 pushes the dispensing assembly closer to the sample vial to add reagents. The entire process requires no manual intervention, avoiding sample contamination caused by manual operation and shortening the derivatization processing time through automation, thus meeting the continuous processing needs of batch samples.

[0032] Specifically, such as Figure 4As shown, the sample trays 8 on both sides of the annular groove 802 are provided with slots 803. The slots 803 are connected to the sample groove 801, and the inner side of the slot 803 is slidably connected with a squeezing block 9. The side of the squeezing block 9 facing the sample bottle has a large friction force, and the four sides of the squeezing block 9 that contact the inner wall of the slot 803 are provided with sealing strips, so as to keep the seal during gas filling and prevent external gas from entering. The outer wall of the lifting cylinder 5 directly above the slot 803 is fixedly connected with an insert block 501.

[0033] In the above technical solution, during the descent of the lifting cylinder 5, the insert block 501 on its outer wall is simultaneously inserted into the slot 803 of the sample tray 8. As the lifting cylinder 5 continues to move downward, the insert block 501 pushes the squeezing block 9 in the slot 803 to slide towards the sample groove 801 until the squeezing block 9 is in close contact with the side wall of the sample bottle, thus achieving automatic clamping and fixing of the sample bottle. This design requires no additional driving components, and the clamping is completed in conjunction with the lifting action of the lifting cylinder 5, ensuring that the sample bottle does not shift during capping and filling, simplifying the device structure, and reducing the risk of failure.

[0034] Furthermore, such as Figure 3 and Figure 5 As shown, a gas cylinder 15 is placed inside the cavity of the support frame 1. An inlet pipe 151 is provided between the gas nozzle of the gas cylinder 15 and the lifting cylinder 5. The two ends of the inlet pipe 151 are connected to the gas cylinder 15 and the lifting cylinder 5, respectively. An exhaust pipe 10 is provided at the top edge of the lifting cylinder 5, and a one-way valve 1001 is sealed to the surface of the exhaust pipe 10. After the lifting cylinder 5 forms a closed space, the gas cylinder 15 can supply inert gas into the lifting cylinder 5 through the inlet pipe 151. At the same time, the original air in the lifting cylinder 5 will be discharged through the exhaust pipe 10. The one-way valve 1001 on the exhaust pipe 10 can prevent external air from entering in reverse. This measure can replace the environment inside the lifting cylinder 5 with an inert gas environment, avoid the oxidation reaction of the sample due to contact with air, and isolate external dust and moisture, providing clean and stable conditions for the derivatization reaction and ensuring the completeness of the derivatization reaction.

[0035] It is important to note that a pressure reducing valve, a solenoid valve, and a one-way valve are sequentially installed on the surface of the inlet pipe 151 between the gas cylinder 15 and the lifting cylinder 5. The pressure reducing valve reduces the high-pressure gas in the gas cylinder 15 to a low-pressure state suitable for the lifting cylinder 5, preventing high pressure from damaging the pipeline or affecting the derivative environment. The solenoid valve controls the gas flow through a circuit, enabling precise start and stop of gas supply in conjunction with the automated process of the device. The one-way valve prevents gas in the lifting cylinder 5 from flowing back into the gas cylinder 15, avoiding contamination of the inert gas in the gas cylinder 15. The three valves work together to achieve a stable, controllable, and clean supply of inert gas to the lifting cylinder 5, ensuring the environmental requirements for the derivative reaction.

[0036] It is worth noting that, such as Figure 4 and Figure 6As shown, the capping assembly includes an electric gripper 7, and hook blocks 701 are fixedly connected to the side walls of the two claws at the bottom of the electric gripper 7. The dispensing assembly includes a fixing frame 12, and a dispensing head 13 is fixedly connected to the surface of the fixing frame 12. The dispensing head 13 is connected to the reagent box 14 at the top of the support frame 1 through a delivery pipe 131. The reagent box 14 is equipped with a liquid pump, which drives the reagent flow. The part of the delivery pipe 131 that passes through the lifting cylinder 5 is sealed, and the delivery pipe 131 is reserved with sufficient length to avoid pulling during the movement of the fixing frame 12. During cap removal, the second electric actuator 6 drives the electric gripper 7 to move downwards. The electric gripper 7 closes, causing the hook block 701 to hook onto the sample vial cap. Then, the second electric actuator 6 lifts the vial to complete the cap removal. The hook block 701 is designed to ensure a firm grip on the cap, preventing it from falling off and causing contamination. During dispensing, the derivatized reagent in the reagent tank 14 is delivered to the dispensing head 13 through the delivery tube 131. The third electric actuator 11 drives the dispensing head 13 to move downwards to the appropriate position for reagent addition. This design achieves precise and automated operation of cap removal and dispensing, improving the stability and reliability of derivatization processing.

[0037] It should be noted that the electric gripper 7 is a mature device, such as the PGEA servo parallel electric gripper 7, which can respond stably and quickly. Here, only the hook block 701 is installed on the surface of its bottom gripper; the rest of the parts remain unchanged. Its power supply line can pass through the pre-drilled hole on the surface of the lifting cylinder 5 to connect to an external power source, and the passage is properly sealed. Since it is a mature existing device, its internal structure and working principle will not be described in detail.

[0038] It is worth noting that a lifting plate 4 is fixedly connected to the upper end of the outer wall of the lifting cylinder 5, and a sliding rod 2 is fixedly connected to the outer surface of the support frame 1. The sliding rod 2 passes through the lifting plate 4 and is slidably connected to the lifting plate 4. A first electric actuator 3 is fixedly connected between the lifting plate 4 and the outer surface of the support frame 1. When the first electric actuator 3 extends or retracts, it can drive the lifting plate 4 to slide up and down along the sliding rod 2, thereby driving the lifting cylinder 5, which is fixed to the lifting plate 4, to rise and fall synchronously. The sliding rod 2 can limit the movement direction of the lifting plate 4 to prevent the lifting cylinder 5 from deviating. This structure provides stable lifting power and guidance for the lifting cylinder 5, ensuring that the lifting cylinder 5 accurately aligns with the annular groove 802 of the sample tray 8, ensuring the sealing of the enclosed space. At the same time, the guiding effect of the sliding rod 2 can reduce the frictional wear between the lifting cylinder 5 and the annular groove 802, extending the service life of the device.

[0039] It should be noted that the chromatograph is a mature existing device. An automatic sampling module is also provided on one side of the sample tray 8 to automatically sample the sample vials placed in the sample slot 801. For example, the Agilent 7820A chromatograph uses a rotating disk for sampling. No modifications have been made to the chromatograph itself. Only derivatization reagents are added to the sample before sampling. Therefore, the working principle and specific structure of the chromatograph itself will not be described in detail.

[0040] It should be noted that the first electric actuator 3 first drives the lifting cylinder 5 to descend to the annular groove 802 to form a seal. Then, the second electric actuator 6 drives the cap removal assembly to move down to complete the cap removal. After cap removal, the third electric actuator 11 pushes the dispensing head 13 to precisely connect with the sample bottle for reagent dispensing. The gas cylinder 15 supplies gas through a combination of a solenoid valve and a pressure reducing valve. After the lifting cylinder 5 is sealed, the gas supply automatically starts and closes after a certain amount of gas is discharged from the exhaust pipe 10, achieving precise volume control. The electric actuator program control and valve linkage used in these designs are all mature technologies in the industry, requiring no complex customization. Moreover, the components are all general standard parts, making procurement and assembly convenient. Those skilled in the art can quickly get started based on conventional electrical control logic and pipeline layout specifications, without needing to overcome additional technical difficulties. The overall implementation is low in difficulty, highly reasonable, and can efficiently complete the device construction and debugging.

[0041] In addition, all components designed in this utility model are general standard parts or components known to those skilled in the art. Their structure and principle can be learned by those skilled in the art through technical manuals or conventional experimental methods. Those skilled in the art can fully implement them, so there is no need to elaborate. The content protected by this utility model does not involve improvements to the internal structure and method.

[0042] The embodiments disclosed herein are preferred embodiments, but are not limited thereto. Those skilled in the art can readily grasp the spirit of this utility model based on the above embodiments and make different extensions and variations. However, as long as they do not depart from the spirit of this utility model, they are all within the protection scope of this utility model.

Claims

1. An automated online pre-column derivatization device for amino acids, comprising a support frame (1) and a lifting cylinder (5), characterized in that, The lifting cylinder (5) is positioned above the sample tray (8). The surface of the sample tray (8) is provided with a number of sample slots (801) arranged in a circumferential array. Each sample slot (801) has an annular groove (802) on the surface of the sample tray (8) outside the sample tray (8). The bottom end of the lifting cylinder (5) is inserted into the annular groove (802). The top end of the lifting cylinder (5) is fixedly connected to a second electric push rod (6). The bottom end of the second electric push rod (6) is located inside the lifting cylinder (5) and is fixedly connected to the cap removal assembly. The outer wall of the lifting cylinder (5) is fixedly connected to a third electric push rod (11). The telescopic end of the third electric push rod (11) is located inside the lifting cylinder (5) and is fixedly connected to the filling assembly.

2. The automated online pre-column derivatization device for amino acids as described in claim 1, characterized in that, The cap removal assembly includes an electric gripper (7), and hooks (701) are fixedly connected to the two side walls of the bottom of the electric gripper (7).

3. The automated online pre-column derivatization device for amino acids as described in claim 1, characterized in that, The dispensing assembly includes a fixed frame (12), on which a dispensing head (13) is fixedly connected. The dispensing head (13) is connected to the reagent box (14) at the top of the support frame (1) through a delivery pipe (131). The part of the delivery pipe (131) that passes through the lifting cylinder (5) is sealed.

4. The automated online pre-column derivatization device for amino acids as described in claim 1, characterized in that, A lifting plate (4) is fixedly connected to the upper end of the outer side wall of the lifting cylinder (5), and a sliding rod (2) is fixedly connected to the outer surface of the support frame (1). The sliding rod (2) passes through the lifting plate (4) and is slidably connected to the lifting plate (4). An electric push rod (3) is fixedly connected between the lifting plate (4) and the outer surface of the support frame (1).

5. The automated online pre-column derivatization device for amino acids as described in claim 1, characterized in that, A gas cylinder (15) is placed inside the cavity of the support frame (1). An air inlet pipe (151) is provided between the gas nozzle of the gas cylinder (15) and the lifting cylinder (5). The two ends of the air inlet pipe (151) are respectively connected to the gas cylinder (15) and the lifting cylinder (5).

6. The automated online pre-column derivatization device for amino acids as described in claim 1, characterized in that, The top edge of the lifting cylinder (5) is provided with an exhaust pipe (10), and a one-way valve (1001) is sealed to the surface of the exhaust pipe (10).

7. The automated online pre-column derivatization device for amino acids as described in claim 1, characterized in that, The sample trays (8) on both sides of the annular groove (802) are provided with slots (803). The slots (803) are connected to the sample trays (801), and the inner side of the slots (803) is slidably connected to the squeezing block (9). The outer wall of the lifting cylinder (5) directly above the slots (803) is fixedly connected to the insert block (501).

Images