Detection platform for determining N-dimethyl nitrosamine in aquatic product by gas chromatography

Abstract

The utility model discloses a detection platform for determining N-dimethyl nitrosamine in aquatic products by using a gas chromatographic method, and belongs to the field of aquatic product detection equipment. Comprising oscillation equipment, water removal equipment and detection equipment, wherein the oscillation equipment comprises an oscillation motor and an oscillation plate arranged at the upper end of the oscillation motor, and a test tube groove plate is arranged at the upper end of the oscillation plate; a stabilizing structure is arranged between the oscillation plate and the test tube groove plate, and the stabilizing structure is composed of an insertion groove formed in the upper end face of the oscillation plate and an insertion plate arranged on the lower end face of the test tube groove plate. The device has the beneficial effects that the test tube groove plate and the oscillation plate are connected through the stable structure, specifically, the insertion plate on the lower end face of the test tube groove plate is inserted into the insertion groove in the upper end face of the oscillation plate matched with the insertion plate, so that when sliding friction occurs between the test tube groove plate and the oscillation plate, the insertion plate is matched with the insertion groove; the test tube groove plate can be prevented from sliding on the oscillation plate, and the test tubes are prevented from inclining during high-speed oscillation.

Description

Technical Field

[0001] The utility model relates to a detection platform for determining N-nitrosodimethylamine in aquatic products by gas chromatography, and belongs to the field of aquatic product detection equipment. Background Art

[0002] N-Nitrosodimethylamine is an organic compound with the chemical formula C 2 H 6 N 2 O is a yellow oily liquid, easily soluble in water, alcohol, ether, and soluble in chloroform; it is toxic and may cause serious damage to health if swallowed or exposed to it for a long time.

[0003] In the food field, N-nitrosodimethylamine mainly exists in aquatic products, so it is necessary to test the concentration of N-nitrosodimethylamine in aquatic products.

[0004] The current detection method refers to GB5009.26-2023 National Food Safety Standard Determination of N-nitrosamines in Foods Method 2 QuEChERS-gas chromatography-mass spectrometry / mass spectrometry;

[0005] A vortex oscillator is required in this method; for the vortex oscillator, reference can be made to a new vortex mixer provided in CN202021403658.4;

[0006] The device fixes the test tube by first placing the test tube on the lower fixing plate having the test tube groove 33, then operating the upper fixing plate to rise and fall, and then pressing on the upper end of the test tube to complete the fixing of the test tube;

[0007] However, the test tube is a glass instrument after all. During the high-speed rotation and oscillation, the wall of the test tube will inevitably collide with the wall of the test tube groove 33 of the lower fixing plate, which will cause the test tube to break. Therefore, the material used for the lower fixing plate is generally rubber or sponge.

[0008] However, the current lower fixed plate is made of rubber or sponge. Although this material has strong static friction and can be placed directly on the vibrating turntable, long-term vibration will also cause dynamic friction between the lower fixed plate and the vibrating turntable, which may cause the test tube to tilt. Utility Model Content

[0009] The utility model aims to provide a detection platform for determining N-nitrosodimethylamine in aquatic products by gas chromatography, which can effectively solve the above-mentioned problems.

[0010] In order to solve the above technical problems, the utility model is achieved through the following technical solutions:

[0011] It includes an oscillation device, a water removal device, and a detection device; wherein, the oscillation device includes an oscillation motor and an oscillation plate arranged at the upper end of the oscillation motor, and a test tube slot plate is arranged at the upper end of the oscillation plate; a stabilizing structure is arranged between the oscillation plate and the test tube slot plate, and the stabilizing structure is composed of a slot arranged on the upper end surface of the oscillation plate and an insert plate arranged on the lower end surface of the test tube slot plate.

[0012] Further: the test tube slot plate includes a stable plate and a flexible plate arranged on the upper end of the stable plate, and the flexible plate is provided with a plurality of arrays of test tube slots; the insert plate is arranged on the lower end surface of the stable plate.

[0013] Furthermore: the oscillation plate, the stabilization plate and the plug plate are made of aluminum alloy.

[0014] Furthermore: the number of the plug boards is four, and they are combined to form a cube frame.

[0015] Further: the cross section of the plug board is trapezoidal.

[0016] Furthermore: the first rubber layer is pasted on all surfaces of the plug board except the surface connected to the stabilizing board, and the second rubber layer is pasted on the groove surface of the slot.

[0017] The beneficial effects are:

[0018] The device connects the test tube slot plate and the oscillation plate through a stable structure, specifically, the plug plate on the lower end surface of the test tube slot plate is inserted into the slot on the upper end surface of the oscillation plate that matches it. With this arrangement, when the test tube slot plate and the oscillation plate are subjected to sliding friction, the cooperation between the plug plate and the slot can prevent the test tube slot plate from sliding on the oscillation plate, thereby preventing the test tube from tilting when oscillating at high speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] For ease of explanation, the present invention is described in detail by the following specific implementations and drawings.

[0020] Figure 1 It is a schematic diagram of the structure of the utility model;

[0021] Figure 2 It is a split diagram of the test tube slot plate and the oscillation plate of the utility model;

[0022] Figure 3 This is a diagram showing the matching of the test tube slot plate and the oscillation plate of the utility model;

[0023] Figure 4 for Figure 3 A partial enlarged view.

[0024] Description of reference numerals:

[0025] 1. Oscillating motor; 2. Oscillating plate; 3. Test tube slot plate; 31. Stable plate; 32. Flexible plate; 33. Test tube slot; 4. Stable structure; 41. Slot; 42. Insert plate; 43. First rubber layer; 44. Second rubber layer. DETAILED DESCRIPTION

[0026] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but cannot be understood as limiting the present invention.

[0027] See also Figure 1-4 This is an embodiment of a detection platform for determining N-nitrosodimethylamine in aquatic products by gas chromatography according to the utility model.

[0028] According to the national standard testing method;

[0029] Step 1: Sample extraction

[0030] Weigh 5 g (accurate to 0.01 g) of the dry product in a 50 mL centrifuge tube, add 5 mL of water, shake and mix [weigh 10 g (accurate to 0.01 g) of the fresh sample in a 50 mL centrifuge tube], add 50 μL of N-nitrosodimethylamine internal standard intermediate solution (1 μg / mL), accurately add 10 mL of acetonitrile, vortex and oscillate for 2 min using the oscillation device of the device, place in a -20 ° C refrigerator for 20 min, add 1 ceramic homogenizer, 4 g of magnesium sulfate and 1 g of sodium chloride, vortex and oscillate for 2 min, place in a refrigerated centrifuge, rotate at 9000 r / min, centrifuge at 10 ° C for 5 min, and the supernatant is to be purified.

[0031] Step 2: Purification

[0032] Add 5 mL of water to the 15 mL purification tube and vortex oscillate, immediately add 5 mL of the supernatant in 1 and vortex oscillate for 1 min through the shaking device of the device, then place in the refrigerated centrifuge of the water removal equipment of the device, centrifuge at 9000 r / min, 10°C for 5 min.

[0033] Step 3: Remove water

[0034] Add the purified sample solution to the purification tube 15mL, 1.6g magnesium sulfate and 0.4g sodium chloride (article number: Q-15S01), vortex oscillation for 2min, place in the refrigerated centrifuge of the dehydration equipment of this device, speed 9000r / min, centrifuge for 5min at 10℃. Take the upper organic phase and filter it through a 0.22μm microporous membrane, and then measure it on the machine.

[0035] The fourth step is to perform detection by gas chromatography-tandem mass spectrometry using the detection equipment of the device.

[0036] The first and second steps of the device both require the use of an oscillation device, which includes an oscillation motor 1 and an oscillation plate 2 arranged at the upper end of the oscillation motor 1, and a test tube slot plate 3 is arranged at the upper end of the oscillation plate 2; a stabilizing structure 4 is arranged between the oscillation plate 2 and the test tube slot plate 3, and the stabilizing structure 4 is composed of a slot 41 arranged on the upper end surface of the oscillation plate 2 and an insert plate 42 arranged on the lower end surface of the test tube slot plate 3.

[0037] First, the use process of the oscillation device is to put the test tube into the test tube slot plate 3, and then install the test tube slot plate 3 on the oscillation plate 2 through the stabilizing structure 4, and turn on the oscillation motor 1 to drive the oscillation plate 2 to rotate and oscillate, and at the same time drive the test tube slot plate 3 to vibrate, at this time, the liquid in the test tube will form a vortex due to the high-speed rotation and oscillation;

[0038] The device is connected between the test tube slot plate 3 and the oscillation plate 2 by a stabilizing structure 4, specifically, the plug plate 42 on the lower end surface of the test tube slot plate 3 is inserted into the slot 41 on the upper end surface of the oscillation plate 2 that matches it. In this way, when the test tube slot plate 3 and the oscillation plate 2 are subjected to sliding friction, the cooperation between the plug plate 42 and the slot 41 can prevent the test tube slot plate 3 from sliding on the oscillation plate 2, thereby preventing the test tube from tilting when oscillating at high speed.

[0039] At the same time, in order to facilitate the above-mentioned setting, the device makes some improvements to the test tube slot plate 3;

[0040] The test tube slot plate 3 comprises a stable plate 31 and a flexible plate 32 arranged at the upper end of the stable plate 31 , wherein a plurality of arrays of test tube slots 33 are arranged in the flexible plate 32 ; the insert plate 42 is arranged at the lower end surface of the stable plate 31 .

[0041] With such arrangement, the part for placing the test tubes and the part for setting the stabilizing structure 4 can be separated. The flexible plate 32 is mainly used to ensure that the test tubes will not be broken. The function of the stabilizing plate 31 is to provide a rigid structure for the insert plate 42, thereby helping the test tube slot plate 3 to be more stable under high-speed oscillation conditions.

[0042] The oscillating plate 2, the stabilizing plate 31 and the inserting plate 42 are made of aluminum alloy.

[0043] With such arrangement, during the high-speed oscillation process, the oscillation plate 2 and the test tube slot plate 3 can be more stably connected together through the stabilizing structure 4 .

[0044] There are four inserting plates 42 , which are combined to form a cubic frame.

[0045] Such arrangement can completely prevent the test tube slot plate 3 from sliding.

[0046] The cross section of the inserting plate 42 is trapezoidal.

[0047] Such arrangement makes it convenient for the staff to take and place the test tube slot plate 3 .

[0048] The first rubber layer 43 is adhered to the surface of the plug board 42 except the surface connected to the stabilizing plate 31 , and the groove surface of the slot 41 is adhered to the second rubber layer 44 .

[0049] In this arrangement, since the cross-section of the insert plate 42 is trapezoidal in order to facilitate the staff to take and place the test tube slot plate 3, this shape setting will be easy to slide during high-speed oscillation. By utilizing the fit of the first rubber layer 43 and the second rubber layer 44, the static friction between the insert plate 42 and the slot 41 can be increased, thereby improving the stability during oscillation.

[0050] The above description is only a specific embodiment of the present invention, but the technical features of the present invention are not limited thereto. Any changes or modifications made by any technician in the field of the present invention are included in the patent scope of the present invention.

Claims

1. A detection platform for determining N-nitrosodimethylamine in aquatic products by gas chromatography, characterized in that: The invention comprises an oscillating device, a water removal device and a detection device; wherein the oscillating device comprises an oscillating motor (1) and an oscillating plate (2) arranged at the upper end of the oscillating motor (1), and a test tube slot plate (3) is arranged at the upper end of the oscillating plate (2); a stabilizing structure (4) is arranged between the oscillating plate (2) and the test tube slot plate (3), and the stabilizing structure (4) is composed of a slot (41) arranged at the upper end surface of the oscillating plate (2) and an insert plate (42) arranged at the lower end surface of the test tube slot plate (3).

2. The detection platform for determining N-nitrosodimethylamine in aquatic products by gas chromatography according to claim 1, characterized in that: The test tube slot plate (3) comprises a stable plate (31) and a flexible plate (32) arranged at the upper end of the stable plate (31), wherein a plurality of arrays of test tube slots (33) are arranged in the flexible plate (32); the insert plate (42) is arranged at the lower end surface of the stable plate (31).

3. The detection platform for determining N-nitrosodimethylamine in aquatic products by gas chromatography according to claim 2, characterized in that: The oscillating plate (2), the stabilizing plate (31) and the inserting plate (42) are made of aluminum alloy.

4. The detection platform for determining N-nitrosodimethylamine in aquatic products by gas chromatography according to claim 3, characterized in that: The number of the inserting plates (42) is four, and they are combined to form a cubic frame.

5. The detection platform for determining N-nitrosodimethylamine in aquatic products by gas chromatography according to claim 4, characterized in that: The insert plate (42) has a trapezoidal cross section.

6. The detection platform for determining N-nitrosodimethylamine in aquatic products by gas chromatography according to claim 5, characterized in that: The first rubber layer (43) is adhered to the inserting plate (42) except the surface connected to the stabilizing plate (31), and the groove surface of the slot (41) is adhered to the second rubber layer (44).

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