A method for detecting cyanide ions in a finished vitamin B12
By combining methods of dissolution, adsorption and desorption, concentration and titration, the problem of inaccurate cyanide ion detection results in vitamin B12 finished products was solved, and accurate cyanide ion detection was achieved, meeting product quality requirements.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- NINGXIA JINMEIYINO ANIMAL BEVERAGE CO LTD
- Filing Date
- 2025-01-06
- Publication Date
- 2026-07-07
AI Technical Summary
In the existing technology, the detection results of cyanide ions in vitamin B12 finished products are inaccurate, mainly because the color of the raw drug in the finished product interferes with the visual inspection results of the inspectors.
A combined approach of dissolution, adsorption and desorption, concentration and titration was adopted. The pH value was adjusted by adding sodium hydroxide solution, and an adsorbent made from sugarcane bagasse cellulose filtrate was used for adsorption and desorption. The mixture was then concentrated using a rotary evaporator, and finally the cyanide content was determined by titration.
It effectively removes color interference from the finished vitamin B12 product, ensuring the accuracy of cyanide ion detection results and meeting the quality requirements of domestic and foreign customers for cyanide ion content <15mg/kg.
Smart Images
Figure BDA0005229584940000031 
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of detection method technology, and in particular relates to a method for detecting cyanide ions in finished vitamin B12. Background Technology
[0002] Vitamin B12 (C) 63 H 88 CoN 14 O 14 Vitamin B12 is a polycyclic aromatic hydrocarbon containing trivalent cobalt. Four reduced pyrrole rings link together to form a corrin macrocycle (similar to porphyrin), which is the core of the vitamin B12 molecule. Vitamin B12 is one of the essential vitamins for the human body. It is mainly found in meat, and soybeans and some herbs also contain B12. Intestinal bacteria can synthesize it, so deficiency is generally not a problem. However, B12 is a vitamin that people with digestive tract diseases are prone to be deficient in, and it is also an essential element for red blood cell production.
[0003] The traditional production process of vitamin B12 is as follows: using denitrifying Pseudomonas aeruginosa, a fermentation process is adopted to obtain vitamin B12 fermentation broth, and then a combination of methods such as organic solvent extraction, membrane filtration, cyanide synthesis, ion exchange resin method, column chromatography and crystallization process are used to produce raw materials for finished vitamin B12 products.
[0004] Because the production process of vitamin B12 involves cyanidation, it contains trace amounts of cyanide ions. Based on the quality requirements of domestic and international customers, it is necessary to test the cyanide ion content in vitamin B12 to ensure product quality. Domestically, colorimetric or titration methods are used to determine the cyanide ion content in finished vitamin B12 products. However, this method has a problem: the raw material of vitamin B12 is dark red in appearance, but turns pale red after dissolving in water. Directly using colorimetric or titration methods interferes with the visual inspection results of the inspectors, ultimately leading to inaccurate cyanide ion detection results. Summary of the Invention
[0005] The purpose of this invention is to overcome the deficiencies in the prior art and provide a method with simple process steps, which removes the influence of the color of the finished vitamin B12 product and ensures the accuracy of cyanide ion detection results.
[0006] The technical solution adopted to achieve the above objectives is as follows:
[0007] A method for detecting cyanide ions in finished vitamin B12 includes the following steps:
[0008] (1) Dissolve
[0009] Add the finished vitamin B12 product to purified water and stir for 20-40 minutes. Then add sodium hydroxide solution to adjust the pH to 9.2-9.6 to obtain a vitamin B12 solution.
[0010] (2) Adsorption and Desorption
[0011] The vitamin B12 solution obtained in step (1) was adsorbed and desorbed to obtain vitamin B12 desorption solution;
[0012] (3) Concentration
[0013] The vitamin B12 solution obtained in step (2) is concentrated to less than 200 ml to obtain vitamin B12 concentrate.
[0014] (4) Detection
[0015] The vitamin B12 concentrate obtained in step (3) was brought to a final volume, and the cyanide content was determined by titration.
[0016] In step (1), the ratio of vitamin B12 product added is: W vitamin B12:V purified water = 10g:1-1.5L; the concentration of sodium hydroxide solution is controlled at 10-20%.
[0017] In step (2), adsorption and desorption refer to:
[0018] 1) Add adsorbent to the resin column and soak it in purified water at a ratio of 1:5-7; the ratio of adsorbent added is: W vitamin B12: W adsorbent = 10g: 112-116g;
[0019] 2) Heat the vitamin B12 solution to 35-45℃, control the flow rate at 0.8-1L / h, and collect the first effluent from the bottom of the resin column;
[0020] 3) After adsorption, purified water is used for elution, with the flow rate of purified water controlled at 1.2-1.4 L / h; the first elution solution is collected, and the elution time is controlled at 240-280 min;
[0021] 4) Mix the first effluent and the first eluent to obtain the vitamin B12 eluent.
[0022] The adsorbent refers to:
[0023] Zinc chloride and deacetylated chitosan were added to the sugarcane bagasse cellulose filtrate, and the mixture was stirred for 20-40 minutes. The temperature was raised to 40-50°C, and dimethylaminoethyl methacrylate was added. The mixture was stirred for another 30-50 minutes, and citric acid was added to adjust the pH to 2.5-3. Then potassium persulfate was added, and the temperature was raised to 70-80°C. The mixture was stirred for another 200-240 minutes, and then dried to obtain a solid product. After pulverizing and passing through a 230-mesh sieve, the adsorbent was obtained.
[0024] The adsorbent addition ratio is as follows:
[0025] W sugarcane bagasse cellulose filtrate: W zinc chloride = 1kg: 20-30g;
[0026] W sugarcane bagasse cellulose filtrate: W deacetylated chitosan = 1 kg : 1-1.2 kg;
[0027] W sugarcane bagasse cellulose filtrate: W dimethylaminoethyl methacrylate = 1 kg : 2.3-2.5 kg;
[0028] The ratio of W sugarcane bagasse cellulose filtrate to W potassium persulfate is 1 kg to 0.3-0.7 kg.
[0029] In step (3), concentration refers to using a rotary evaporator with the temperature controlled at 120-150℃, the vacuum degree controlled at 0.4-0.6MPa, and the rotation speed controlled at 30-50r / min.
[0030] In step (4), titration refers to:
[0031] 1) Reagents and materials:
[0032] Silver Indicator (0.02%): Weigh 0.01g of rose-red silver and dissolve it in 50ml of acetone.
[0033] Silver nitrate standard solution (0.01 mol / L): Weigh 1.7550 g of silver nitrate, dissolve it in water, dilute to 1000 ml, store in a brown reagent bottle, shake well, and use after standardization;
[0034] 2) Operating steps:
[0035] Add the concentrated vitamin B12 solution to the conical flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is when the solution changes from yellow to bright orange-red. At the same time, perform a blank test.
[0036] 3) Calculate: CN － The content is calculated using the following formula:
[0037]
[0038] In the formula:
[0039] c: Concentration of silver nitrate standard solution (mol / L);
[0040] V: Volume (ml) of silver nitrate standard solution consumed in the titration;
[0041] V1: Volume of water (L);
[0042] 52.02: Molar mass (g) of CN-.
[0043] The technical effects achieved by this invention are as follows:
[0044] For domestic and international customers who require that the cyanide ion content in finished vitamin B12 raw materials be <15mg / kg, the method described in this patent can effectively detect the cyanide ion content, thereby ensuring product quality. Detailed Implementation
[0045] The invention is illustrated below with examples. It should be understood that these examples are for illustrative purposes only and not for limiting the invention. The scope and core content of the invention are defined by the claims.
[0046] Sugarcane bagasse cellulose filtrate is a byproduct of sugarcane refining. Sugarcane is coarsely ground and finely ground to obtain granules, which are then hot-pressed in a press, pulped in a pulping machine, and separated to obtain sugarcane bagasse cellulose filtrate.
[0047] Example 1
[0048] 20g of finished vitamin B12 raw material.
[0049] (1) Dissolve
[0050] Add the finished vitamin B12 raw material to 2L of purified water, stir for 20 minutes, then add 10% sodium hydroxide solution to adjust the pH to 9.2.
[0051] (2) Adsorption and desorption
[0052] The vitamin B12 solution was adsorbed and desorbed to obtain 4.3 L of the desorbed solution.
[0053] (3) Concentration
[0054] The eluent was concentrated to 196 ml.
[0055] (4) Detection: Add the concentrated solution to the conical flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is when the solution changes from yellow to bright orange-red.
[0056] Calculations show that the cyanide ion content in the finished vitamin B12 product is 11.4 mg / kg.
[0057] Example 2
[0058] 20g of finished vitamin B12 raw material.
[0059] (1) Dissolve
[0060] Add the finished vitamin B12 raw material to 2.4L of purified water, stir for 25 minutes, then add 12% sodium hydroxide solution to adjust the pH to 9.3.
[0061] (2) Adsorption and desorption
[0062] The vitamin B12 solution was adsorbed and desorbed to obtain 4.9 L of the desorbed solution.
[0063] (3) Concentration
[0064] The eluent was concentrated to 190 ml.
[0065] (4) Detection: Add the concentrated solution to the conical flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is when the solution changes from yellow to bright orange-red.
[0066] Calculations show that the cyanide ion content in the finished vitamin B12 product is 12.2 mg / kg.
[0067] Example 3
[0068] 20g of finished vitamin B12 raw material.
[0069] (1) Dissolve
[0070] Add the finished vitamin B12 raw material to 2.6L of purified water, stir for 30 minutes, then add 15% sodium hydroxide solution to adjust the pH to 9.4.
[0071] (2) Adsorption and desorption
[0072] The vitamin B12 solution was adsorbed and desorbed to obtain 5.4 L of the desorbed solution.
[0073] (3) Concentration
[0074] The eluent was concentrated to 198 ml.
[0075] (4) Detection: Add the concentrated solution to the conical flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is when the solution changes from yellow to bright orange-red.
[0076] Calculations show that the cyanide ion content in the finished vitamin B12 product is 10.4 mg / kg.
[0077] Example 4
[0078] 20g of finished vitamin B12 raw material.
[0079] (1) Dissolve
[0080] Add the finished vitamin B12 raw material to 2.8L of purified water, stir for 35 minutes, then add 17% sodium hydroxide solution to adjust the pH to 9.5.
[0081] (2) Adsorption and desorption
[0082] The vitamin B12 solution was adsorbed and desorbed to obtain 6.5 L of the desorbed solution.
[0083] (3) Concentration
[0084] The eluent was concentrated to 196 ml.
[0085] (4) Detection: Add the concentrated solution to the conical flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is when the solution changes from yellow to bright orange-red.
[0086] Calculations show that the cyanide ion content in the finished vitamin B12 product is 11.8 mg / kg.
[0087] Example 5
[0088] 20g of finished vitamin B12 raw material.
[0089] (1) Dissolve
[0090] Add the finished vitamin B12 raw material to 3L of purified water, stir for 40 minutes, then add 20% sodium hydroxide solution to adjust the pH to 9.6.
[0091] (2) Adsorption and desorption
[0092] The vitamin B12 solution was adsorbed and desorbed to obtain 7.1 L of the desorbed solution.
[0093] (3) Concentration
[0094] The eluent was concentrated to 196 ml.
[0095] (4) Detection: Add the concentrated solution to the conical flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is when the solution changes from yellow to bright orange-red.
[0096] Calculations show that the cyanide ion content in the finished vitamin B12 product is 10.7 mg / kg.
[0097] Example 6
[0098] 20g of finished vitamin B12 raw material.
[0099] (1) Dissolve
[0100] Add the finished vitamin B12 raw material to 2.2L of purified water, stir for 39 minutes, then add 11% sodium hydroxide solution to adjust the pH to 9.3.
[0101] (2) Adsorption and desorption
[0102] The vitamin B12 solution was adsorbed and desorbed to obtain 4.9 L of the desorbed solution.
[0103] (3) Concentration
[0104] The eluent was concentrated to 199 ml.
[0105] (4) Detection: Add the concentrated solution to the conical flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is when the solution changes from yellow to bright orange-red.
[0106] Calculations show that the cyanide ion content in the finished vitamin B12 product is 11.4 mg / kg.
[0107] Example 7
[0108] 20g of finished vitamin B12 raw material.
[0109] (1) Dissolve
[0110] Add the finished vitamin B12 raw material to 2.9L of purified water, stir for 31 minutes, then add 18% sodium hydroxide solution to adjust the pH to 9.5.
[0111] (2) Adsorption and desorption
[0112] The vitamin B12 solution was adsorbed and desorbed to obtain 5.9 L of the desorbed solution.
[0113] (3) Concentration
[0114] The eluent was concentrated to 190 ml.
[0115] (4) Detection: Add the concentrated solution to the conical flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is when the solution changes from yellow to bright orange-red.
[0116] Calculations show that the cyanide ion content in the finished vitamin B12 product is 10.7 mg / kg.
[0117] Comparative Example 1
[0118] 20g of finished vitamin B12 raw material (consistent with the raw material used in Example 1).
[0119] (1) Dissolve
[0120] Add the finished vitamin B12 raw material to 3L of purified water, stir for 31 minutes, then add 18% sodium hydroxide solution to adjust the pH to 9.5.
[0121] (2) Concentration
[0122] The eluent was concentrated to 190 ml.
[0123] (3) Detection: Add the concentrated solution to the conical flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is when the solution changes from yellow to bright orange-red.
[0124] Calculations show that the cyanide ion content in the finished vitamin B12 product is 14.6 mg / kg.
[0125] Comparative Example 2
[0126] 2g of finished vitamin B12 raw material (same as the raw material used in Example 2).
[0127] (1) Dissolve
[0128] Add the finished vitamin B12 raw material to 0.2L of purified water, stir for 30 minutes, and stop stirring after visually confirming that it has completely dissolved.
[0129] (2) Detection: Add the above vitamin B12 solution to an Erlenmeyer flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is when the solution changes from yellow to bright orange-red.
[0130] Calculations show that the cyanide ion content in the finished vitamin B12 product is 15.3 mg / kg.
Claims
1. A method for detecting cyanide ions in finished vitamin B12, comprising the following steps: (1) Dissolve Add the finished vitamin B12 product to purified water and stir for 20-40 minutes. Then add sodium hydroxide solution to adjust the pH to 9.2-9.6 to obtain a vitamin B12 solution. (2) Adsorption and Desorption The vitamin B12 solution obtained in step (1) was adsorbed and desorbed to obtain vitamin B12 desorption solution; (3) Concentration The vitamin B12 solution obtained in step (2) is concentrated to less than 200 ml to obtain vitamin B12 concentrate. (4) Detection The vitamin B12 concentrate obtained in step (3) was brought to a final volume, and the cyanide content was determined by titration.
2. The detection method according to claim 1, characterized in that... In step (1), the ratio of vitamin B12 product added is: W vitamin B12:V purified water = 10g:1-1.5L; the concentration of sodium hydroxide solution is controlled at 10-20%.
3. The detection method according to claim 1, characterized in that... In step (2), adsorption and desorption refer to: 1) Add adsorbent to the resin column and soak it in purified water at a ratio of 1:5-7; the ratio of adsorbent added is: W vitamin B12: W adsorbent = 10g: 112-116g; 2) Heat the vitamin B12 solution to 35-45℃, control the flow rate at 0.8-1L / h, and collect the first effluent from the bottom of the resin column; 3) After adsorption, purified water is used for elution, with the flow rate of purified water controlled at 1.2-1.4 L / h; the first elution solution is collected, and the elution time is controlled at 240-280 min; 4) Mix the first effluent and the first eluent to obtain the vitamin B12 eluent.
4. The detection method according to claim 3, characterized in that... The adsorbent refers to: Zinc chloride and deacetylated chitosan were added to the sugarcane bagasse cellulose filtrate, and the mixture was stirred for 20-40 minutes. The temperature was raised to 40-50°C, and dimethylaminoethyl methacrylate was added. The mixture was stirred for another 30-50 minutes, and citric acid was added to adjust the pH to 2.5-3. Then potassium persulfate was added, and the temperature was raised to 70-80°C. The mixture was stirred for another 200-240 minutes, and then dried to obtain a solid product. After pulverizing and passing through a 230-mesh sieve, the adsorbent was obtained.
5. The detection method according to claim 4, characterized in that... The adsorbent addition ratio is: W sugarcane bagasse cellulose filtrate: W zinc chloride = 1kg: 20-30g; W sugarcane bagasse cellulose filtrate: W deacetylated chitosan = 1 kg : 1-1.2 kg; W sugarcane bagasse cellulose filtrate: W dimethylaminoethyl methacrylate = 1 kg : 2.3-2.5 kg; W sugarcane bagasse cellulose filtrate: W potassium persulfate = 1 kg : 0.3-0.7 kg.
6. The detection method according to claim 1, characterized in that... In step (3), concentration refers to using a rotary evaporator with the temperature controlled at 120-150℃, the vacuum degree controlled at 0.4-0.6MPa, and the rotation speed controlled at 30-50r / min.
7. The detection method according to claim 1, characterized in that... In step (4), titration refers to: 1) Reagents and materials: Silver Indicator (0.02%): Weigh 0.01g of rose-red silver and dissolve it in 50ml of acetone. Silver nitrate standard solution (0.01 mol / L): Weigh 1.7550 g of silver nitrate, dissolve it in water, dilute to 1000 ml, store in a brown reagent bottle, shake well, and use after standardization; 2) Operating steps: Add the concentrated vitamin B12 solution to an Erlenmeyer flask, make up to 250 ml, add 0.5 ml of 0.02% silver nitrate indicator solution, and titrate with silver nitrate standard solution [c(AgNO3)=0.01mol / L]. The endpoint is defined as the color changing from yellow to bright orange-red. At the same time, perform a blank test. 3) Calculate: CN － The content is calculated using the following formula: In the formula: c: Concentration of silver nitrate standard solution (mol / L); V: Volume (ml) of silver nitrate standard solution consumed in the titration; V1: Volume of water (L); 52.02: Molar mass (g) of CN-.