CN113406069B - Method for detecting iron ions in hydrolysate prepared from cornu bubali powder and application of method in qingkailing hydrolysate - Google Patents
Method for detecting iron ions in hydrolysate prepared from cornu bubali powder and application of method in qingkailing hydrolysate Download PDFInfo
- Publication number
- CN113406069B CN113406069B CN202110667741.5A CN202110667741A CN113406069B CN 113406069 B CN113406069 B CN 113406069B CN 202110667741 A CN202110667741 A CN 202110667741A CN 113406069 B CN113406069 B CN 113406069B
- Authority
- CN
- China
- Prior art keywords
- hydrolysate
- solution
- iron ions
- content
- shaking
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/75—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated
- G01N21/77—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator
- G01N21/78—Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator producing a change of colour
- G01N21/79—Photometric titration
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/38—Diluting, dispersing or mixing samples
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N31/00—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods
- G01N31/16—Investigating or analysing non-biological materials by the use of the chemical methods specified in the subgroup; Apparatus specially adapted for such methods using titration
- G01N31/162—Determining the equivalent point by means of a discontinuity
Abstract
The invention discloses a method for detecting iron ions in hydrolysate prepared from buffalo horn powder and application of the method in qingkailing hydrolysate. The method pretreats the hydrolysate to be detected, adds the iodo-compound containing acetyl, solves the problem that accurate determination is difficult due to the color reversion phenomenon of the end point when the iron ions contained in the hydrolysate are determined by using the existing indirect iodometry, eliminates the interference of the background color of the hydrolysate, realizes the purpose of rapidly judging the change of the end point through intuitive and clear color fading, ensures the accuracy and stability of the detection result, can perform real-time detection in industrial production, greatly improves the production efficiency and ensures the product quality.
Description
Technical Field
The invention relates to the technical field of iron ion detection. More particularly, relates to a method for detecting iron ions in hydrolysate prepared from buffalo horn powder and application of the method in qingkailing hydrolysate.
Background
The buffalo horn powder is an important variety in the traditional Chinese medicine clinical and traditional Chinese medicine pharmaceutical industry, and has the effects of clearing heat and calming. The aqueous cornu bubali powder is generally prepared from hydrolysate, and iron ions are inevitably introduced due to the influence of raw and auxiliary materials, reaction equipment and the like in the process of preparing the hydrolysate from the cornu bubali powder. Iron ions are one of the essential trace elements of human body, and are involved in hemoglobin synthesis, cell respiration, electron transfer, and DNA synthesis, and also in enzymatic activity reaction. However, it has been shown that excessive intake of iron ions can also cause many diseases in the body, such as heart and liver diseases, senile dementia, parkinson's disease, tumors, etc. Therefore, it is necessary to detect the iron ion content in the hydrolysate.
The prior art mainly comprises a potassium thiocyanate colorimetric method, a potassium ferricyanide titration method, an o-phenanthrene spectrophotometry method, a cerium sulfate titration method, a portable ferric ion detector, an indirect iodometry method and the like. However, these methods are not adequate for use with hydrolysates. For example, the colorimetric method of potassium thiocyanate and the titration method of potassium ferricyanide judge the content of iron ions in solution through the color change after the color reagent reacts with the iron ions, the reaction is very sensitive, and the reaction can be carried out with KSCN or K only by trace amount of iron ions 3 Fe(CN) 6 A darker color reaction is generated, but most of hydrolysate has certain background color (such as brownish red, brown or earthy yellow), erroneous judgment that the content of iron ions exceeds the limit easily occurs, and the error of the colorimetric result of the method is larger; the indirect iodometry has a large measurement range and is simple and convenient to operate, but in actual operation, when the conventional indirect iodometry is adopted to detect the hydrolysate, the phenomenon of repeated color reversion of an end point often occurs, so that the end point judgment is inaccurate, the background color of the hydrolysate can influence the end point color judgment during detection, and the accuracy of the determination is reduced; similarly, the o-phenanthroline spectrophotometry is only suitable for analyzing colorless samples to be detected and is not suitable for detecting hydrolysate with background color; although the cerium sulfate titration method can accurately detect the content of iron ions, the iron ions need to be detected under the condition that a sample is cooled to room temperature, and for field analysis, the method is relatively complicated in operation, poor in timeliness and reduced in production efficiency; a portable iron ion detector belongs to a precise instrument, cannot be placed on a workshop production site, has low measurement limit, requires the concentration of iron ions of a sample to be measured to be below 10mg/L, andthe pH value of the hydrolysate is medium-strong acid, and the probe of the portable iron ion detector is easily corroded, so that the hydrolysate has the characteristics of low limit, incapability of being placed in a workshop production field, small coverage, unsuitability for production and use, and the like, and cannot meet the requirement of rapid on-site monitoring.
A series of QINGKAILING products, such as QINGKAILING oral liquid, QINGKAILING injection, QINGKAILING granule, QINGKAILING Capsule, etc., are prepared by hydrolyzing intermediate hydrolysate of cornu Bubali powder and Concha Margaritifera powder with concentrated sulfuric acid, precipitating, and filtering. One of the quality requirements of the intermediate product hydrolysate relates to the limit control of iron ions. In the actual production, excessive iron ions can affect the stability, color and taste of qingkailing series products, even cause the precipitation of two liquid preparations of qingkailing injection and oral liquid, and cause quality accidents. From the process route analysis, the iron ions in the hydrolysate can be derived from two sources: firstly, feeding and carrying in auxiliary materials in the preparation process of hydrolysate; secondly, the reaction kettle and the production pipeline are introduced in the production process. In terms of the first source, because the production process is deterministic and stable, and each batch of raw and auxiliary materials has a relevant ion detection report, the iron ions brought into the hydrolysate by the fed materials and the raw and auxiliary materials are known numbers; while the second source, which is less controlled by the introduction of iron ions from the production line and may vary from batch to batch, is unknown as to whether or not iron ions are introduced or the amount of iron ions introduced. In the actual production process, iron ions are inevitably brought into the hydrolysate, excessive iron ions influence the quality of the qingkailing series products, and according to the experience of an applicant, the limit of the iron ions needs to be controlled within 0.0448mg/mL, so that in the preparation process of the qingkailing series products, whether the iron ion content of the intermediate product hydrolysate exceeds the limit needs to be detected and monitored, and a judgment can be quickly and efficiently made on a workshop production field, so that the method is a release basis for the subsequent process steps. Meanwhile, whether the iron ion content in the hydrolysate exceeds the limit or not is quickly judged, and whether the production pipeline is abnormal or not can be measured, so that greater production resource waste is avoided.
Based on the defects in the prior art or the current situation that the detection method is not suitable for hydrolysate products prepared from buffalo horn powder, a method for quickly and accurately detecting iron ions in the hydrolysate prepared from the buffalo horn powder and a method for quickly judging whether the content of the iron ions in the qingkailing hydrolysate exceeds the limit are urgently needed to be used as a release basis of the subsequent process steps and improve the production efficiency.
Disclosure of Invention
The invention aims to overcome the defects and shortcomings of the prior art and provide a method for detecting iron ions in hydrolysate.
The invention also aims to provide application of the method for detecting iron ions in hydrolysate in the aspect of detecting iron ions in qingkailing hydrolysate.
The invention also aims to provide a method for rapidly judging whether the content of iron ions in the qingkailing hydrolysate exceeds the limit.
The above purpose of the invention is realized by the following technical scheme:
a method for detecting iron ions in hydrolysate adopts indirect iodometry; wherein, the hydrolysate is pretreated before detection, and the pretreatment comprises the following steps: adding iodo compound containing acetyl into the hydrolysate, and shaking up to obtain pretreatment solution;
the hydrolysate is prepared from cornu Bubali powder.
Compared with other iron ion detection methods, the indirect iodometry method has the advantages of simplicity, convenience and quickness, but when the indirect iodometry method is applied to hydrolysate, the titration end point is subjected to repeated color reversion, and the iron ions cannot be accurately detected. Through research and analysis, the hydrolysate prepared by hydrolyzing buffalo horn powder contains sulfhydryl (-SH) compounds, such as cysteine, etc., wherein S atom of sulfhydryl (-SH) has strong electronic activity, and when iron ions (Fe) exist in the solution 2+ Or Fe 3+ ) Mercapto (-SH) is readily available for reaction with iron ions (Fe) 2+ Or Fe 3+ ) A coordination complex reaction occurs, which is a reversible reaction, followed by Fe 3+ Ions with I - With Fe in redox reactions of ions 3+ The ions are consumed to sequentially release the coordination complex and release Fe 3+ Ion, toMaking sodium thiosulfate or Fe in hydrolysate 3 + Ions can not rapidly and completely react with iodine, and after oscillation, blue color of a solution system repeatedly appears between fading and returning blue color, so that the final result judgment is unstable, and the problems of large error of test data, poor reproducibility and the like are caused. In addition, iron ions in the hydrolysate and mercapto (-SH) coordinate and complex to form a complex which appears as a brownish red, brown or earthy yellow and the like and becomes the background color of the hydrolysate, thereby influencing the color judgment during detection.
Based on the reasons, the inventor improves the conventional indirect iodometry, the hydrolysate to be detected is pretreated, an iodo compound containing acetyl is added, the iodo compound containing acetyl can rapidly react with mercapto (-SH) of compounds such as cysteine and the like, so that iron ions are changed back to a free state from a complex, the problem that accurate determination is difficult due to repeated color reversion of an end point in the detection process of the hydrolysate is solved, and meanwhile, after the coordination complex reaction is removed, the background color of the hydrolysate disappears to form a colorless solution, so that the interference of the background color of the hydrolysate is eliminated, and the reaction equation is as follows:
R-SH+ICH 2 COR 1 →R-S-CH 2 COR 1 +HI。
preferably, the acetyl group-containing iodo compound is iodoacetamide and/or iodoacetic acid.
The method can be well applied to the detection of iron ions in the qingkailing oral liquid hydrolysate, and comprises a qualitative method for quickly judging the content limit and a quantitative method for detecting the specific content.
The invention provides a method for rapidly judging whether the content of iron ions in qingkailing hydrolysate exceeds the limit, which comprises the following steps:
s1, pretreatment: adding iodo compound containing acetyl into the hydrolysate, and shaking up to obtain pretreatment solution;
s2, judging a result:
s2-1, adding an acid solution into the pretreatment solution, and shaking up;
s2-2, adding a starch indicating solution, and shaking up to make the solution system blue;
s2-3, adding a sodium thiosulfate standard solution, shaking up, converting the dosage of the sodium thiosulfate standard solution according to the iron ion content standard and a stoichiometric theory, and obtaining the formula as follows:
in the formula: v 1 Is the volume of the sodium thiosulfate standard solution, mL;
C 1 the concentration is the concentration of a sodium thiosulfate standard solution, mol/L;
C 2 the content of iron ions in the hydrolysate is g/mL;
V 2 the volume of the hydrolysate is mL;
s2-4, judging whether the content of iron ions exceeds the limit:
when the blue color of the solution system is faded, the content of iron ions is judged to be qualified;
when the blue color of the solution system is not faded out, the content of the iron ions is judged to be over-limit.
The qingkailing hydrolysate is prepared with buffalo horn powder and/or nacre powder and through hydrolysis in concentrated sulfuric acid, adding certain amount of Ca (OH) 2 Precipitating and filtering to obtain the product. The compound containing sulfydryl (-SH) in the hydrolysate is mainly generated by hydrolyzing protein in the buffalo horn powder into amino acid and decomposing amino acid groups. The content of amino acid in the hydrolysate is less influenced by the using amount of the buffalo horn powder, and in the preparation process of the hydrolysate, the liquid amount of the extracting solution is correspondingly increased along with the increase of the buffalo horn powder, and finally the buffalo horn powder is concentrated to a certain volume. Generally, the amino acid content of the hydrolysate is in the range of 0.01-0.1 g/mL.
Preferably, the mass volume ratio of the iodo compound containing acetyl to the hydrolysate is 0.2-1g.
Preferably, in the present invention, especially in step s1, the temperature of the hydrolysate is between room temperature and 70 ℃.
More preferably, in step s1, the temperature of the hydrolysate is 50 to 70 ℃. In the production process, the temperature of the hydrolysate is usually 50-70 ℃, and the method can realize direct sampling detection in the production field without cooling treatment, simplify the operation and ensure that the detection is quicker.
The method and the step S2-1 of the invention are that acid solution is added, and Fe in the hydrolysate is shaken up in the process of oscillation 2+ Ion dissolved oxygen in liquid and acid radical ion H of acid solution + Is oxidized into Fe 3+ Ion, the reaction equation is as follows:
4Fe 2+ +O 2 +4H + ＝4Fe 3+ +2H 2 O
in addition, HI generated after reaction of iodo compound containing acetyl group in step S1, excess acid ion H in step S2-1 + Can free reducing I - Ions, possibly with Fe having a strong oxidizing property 3+ Ion oxidation-reduction reaction to generate I 2 The reaction equation is as follows:
2Fe 3+ +2I - ＝2Fe 2+ +I 2
further, in the step S2-2, starch indicating liquid is added, and the hydrolysate is in a blue reaction.
Preferably, in the step S2-1, the volume ratio of the acidic solution to the pretreatment solution is 0.1 to 1:1.
More preferably, in step S2-1, the volume ratio of the acidic solution to the pretreatment liquid is 0.1 to 0.5.
Preferably, in the step S2-1, the concentration of the acid solution is 0.01-6.0 mol/L.
Preferably, in step S2-1, the acidic solution is sulfuric acid, hydrochloric acid, acetic acid, potassium dihydrogen phosphate and/or sodium dihydrogen phosphate.
Further, in step S2-3, a quantitative sodium thiosulfate standard solution is added, the amount of the sodium thiosulfate standard solution is converted according to the stoichiometric theory according to the standard of the content of iron ions, and the formula is as follows:
in the formula: v 1 The volume of the standard solution of sodium thiosulfate is mL;
C 1 the concentration is the concentration of a sodium thiosulfate standard solution, mol/L;
C 2 the content of iron ions in the hydrolysate is g/mL;
V 2 is the volume of the hydrolysate, mL;
preferably, in step S2-3, the concentration of the standard solution of sodium thiosulfate is 0.001-0.01 mol/L.
Preferably, in step S2-3, the iron ion content is 0.0448mg/mL.
Further, in step S2-4, judging whether the content of iron ions exceeds the limit according to whether blue color in the solution system is faded or not:
when the blue color of the solution system is faded, the content of iron ions is judged to be qualified;
when the blue color of the solution system is not faded, the content of the iron ions is judged to be out of limit.
The relevant reaction formula is as follows:
2NaS 2 O 3 +I 2 ＝Na 2 S 4 O 6 +2NaI
step S2-4, if the blue color of the solution system is faded, the quantitative addition of the sodium thiosulfate standard solution is shown to completely consume Fe in the hydrolysate 3+ I by oxidation of ions 2 That is, the iron ion content (Fe) in the hydrolysate is shown 2+ And/or Fe 3+ ) Within the limits of preparation; on the contrary, if the blue color of the solution system is not faded, the iron ion content (Fe) in the hydrolysate is shown 2+ And/or Fe 3 + ) The preparation limit is exceeded. Therefore, the method of the invention can visually and definitely observe whether the color in the hydrolysate is faded away or not, accurately determine the content of the iron ions in the hydrolysate, reduce human errors, have accurate detection results, can be applied to on-site rapid detection and greatly improve the production efficiency.
Compared with the prior art, the invention has the following beneficial effects:
the invention provides a method for detecting iron ions in hydrolysate prepared from buffalo horn powder and application of the method in qingkailing hydrolysate. The method is simple, feasible, scientific and accurate in route design improvement based on an indirect iodometry method, based on the characteristics of the hydrolysate, the hydrolysate to be detected is pretreated, and the iodo-compound containing acetyl is added, so that the problem that accurate determination is difficult due to the repeated color reversion of the endpoint of the hydrolysate when the hydrolysate is determined by the existing indirect iodometry method is solved, the interference of the background color of the hydrolysate is eliminated, the endpoint change can be judged by directly and clearly fading the color, and the accuracy and the stability of the detection result are effectively improved. The invention is suitable for detecting iron ions in qingkailing hydrolysate, can take hydrolysate at 50-70 ℃ on site as a sample for detection in a production field, can quickly and accurately judge whether the iron ion content of the hydrolysate exceeds the limit, provides a release basis for the subsequent process steps, and can be used for measuring the basis of whether production equipment pipelines such as iron pipelines have abnormity or not and the basis of whether the examination needs to be carried out or not by means of the color judgment result, thereby avoiding greater production resource waste. Therefore, the detection method is accurate and stable, can be applied to on-site rapid detection, greatly improves the production efficiency and ensures the product quality.
Detailed Description
The present invention is further illustrated by the following specific examples, which are not intended to limit the invention in any way. Reagents, methods and apparatus used in the present invention are conventional in the art unless otherwise indicated.
Unless otherwise indicated, reagents and materials used in the following examples are commercially available.
The invention takes qingkailing hydrolysate as an example for experiment. Wherein iron ions (Fe) in QINGKAILING hydrolysate 2+ And/or Fe 3+ ) The internal control standard of (2) is as follows: the upper threshold of iron ions was 0.0448mg/mL. Through research and analysis, the hydrolysate is prepared from cornu Bubali powder and MargaritaHydrolyzing the mother powder with concentrated sulfuric acid, adding a certain amount of Ca (OH) 2 Precipitating and filtering to obtain the product. The buffalo horn powder and the nacre powder which are used as raw materials for preparing the hydrolysate are subjected to factory inspection before feeding, metal ions contained in the buffalo horn powder and the nacre powder are determined, iron ions belong to trace levels, and the influence on the iron ion content in the hydrolysate and subsequent qingkailing finished products is negligible. And Ca (OH) as an auxiliary material for preparing hydrolysate 2 According to theoretical calculation and actual production statistics, iron ions with the mass not more than 0.2% of the mass of the iron ions are introduced, and therefore the upper limit threshold of the iron ions in the qingkailing hydrolysate is obtained through conversion.
Example 1 verification of stability and accuracy
Taking the determination of the iron ions of the qingkailing hydrolysate as an example, the iron ion content in the hydrolysate is detected by adopting the following method.
Preparation of starch indicator liquid: weighing 0.5g of soluble starch, adding 5mL of water, stirring uniformly, slowly adding into 100mL of boiling water, stirring, adding, boiling for 2min, cooling to room temperature, and collecting supernatant.
The method comprises the following steps:
indirect iodometry: and (3) putting 10mL of brownish red hydrolysate at the temperature of 50 +/-5 ℃ into a transparent tube, adding 1mL of 6mol/L hydrochloric acid, shaking up, adding 2g of potassium iodide powder, shaking up, adding 2mL of prepared starch indicating solution, enabling the hydrolysate to be blue, adding 0.001mol/L sodium thiosulfate standard solution, and titrating until the blue is faded to the end point.
The method 2 comprises the following steps:
pretreatment: 10mL of brownish red hydrolysate at 50 +/-5 ℃ is taken to be put into a transparent tube, 10g of iodoacetamide is added, and the mixture is fully shaken up to obtain the pretreatment liquid.
Indirect iodometry: adding 1mL of 6mol/L hydrochloric acid into the pretreatment liquid, shaking up, adding 2g of potassium iodide powder, shaking up, adding 2mL of prepared starch indicator liquid, enabling the hydrolysate to be blue, adding 0.001mol/L sodium thiosulfate standard solution, and titrating until the blue color is faded.
The method 1 and the method 2 are adopted for repeating the experiment for multiple times, the method 1 is used for detecting for 20 times and the method 2 is used for detecting for 20 times in each experiment, comparative analysis is carried out, the experiment results are recorded, and the overall experiment results are approximately the same. Table 1 illustrates the experimental procedure and comparative results in which one was randomly selected.
TABLE 1 stability and accuracy verification results
As can be seen from the results in Table 1, compared with the conventional indirect iodometry (method 1), the method 2 for pretreating the hydrolysate has the advantages of obvious titration endpoint change and good result reproducibility, so that the method obviously improves the accuracy and stability of detection.
Example 2 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: 10mL of brownish red hydrolysate at 50 +/-5 ℃ is taken to be put into a transparent tube, 10g of iodoacetamide is added, and the mixture is fully shaken up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.02g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L hydrochloric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, titrating with 0.001mol/L sodium thiosulfate standard solution, shaking and shaking for 30 seconds;
s2-4, fading blue, oscillating the solution for 30 seconds, standing for 3-5 min, and showing that the hydrolysate is colorless 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 3 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: 10mL of brownish red hydrolysate at 50 +/-5 ℃ is taken to be put into a transparent tube, 5g of iodoacetamide is added, and the mixture is fully shaken up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.01g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L hydrochloric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, the blue color is faded, the solution is oscillated for 30 seconds again, and the solution is still colorless after being placed for 3 to 5 minutes, which shows that the hydrolysate is Fe 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 4 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: taking 10mL of brownish red hydrolysate at 50 +/-5 ℃ into a transparent tube, adding 2g of iodoacetamide, and fully shaking up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.02g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L hydrochloric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, the blue color is faded, the solution is oscillated for 30 seconds again, and the solution is still colorless after being placed for 3 to 5 minutes, which shows that the hydrolysate is Fe 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 5 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: taking 10mL of brownish red hydrolysate at 50 +/-5 ℃ into a transparent tube, adding 2g of iodoacetamide, and fully shaking up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.02g/mL.
S2, judging a result:
s2-1, adding 1mL of 0.01mol/L hydrochloric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, the blue color is faded, the solution is oscillated for 30 seconds again, and the solution is still colorless after being placed for 3 to 5 minutes, which shows that the hydrolysate is Fe 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 6 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: 10mL of brownish red hydrolysate at 50 +/-5 ℃ is taken to be put into a transparent tube, 2g of iodoacetamide is added, and the mixture is fully shaken up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.02g/mL.
S2, judging a result:
s2-1, adding 10mL of 0.01mol/L hydrochloric acid, and shaking uniformly;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, the blue color is faded, the solution is oscillated for 30 seconds again, and the solution is still colorless after being placed for 3 to 5 minutes, which shows that the hydrolysate is Fe 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 7 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: taking 10mL of brownish red hydrolysate at 50 +/-5 ℃ into a transparent tube, adding 2g of iodoacetamide, and fully shaking up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.02g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L sulfuric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, fading blue, oscillating the solution for 30 seconds, standing for 3-5 min, and showing that the hydrolysate is colorless 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 8 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: 10mL of brownish red hydrolysate at 50 +/-5 ℃ is taken to be put into a transparent tube, 2g of iodoacetamide is added, and the mixture is fully shaken up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.02g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L potassium dihydrogen phosphate, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, the blue color is faded, the solution is shaken for 30 seconds again, and the solution is still colorless after being placed for 3 to 5min, which represents that Fe 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 9 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: taking 10mL of brownish red hydrolysate at 50 +/-5 ℃ into a transparent tube, adding 2g of iodoacetic acid, and fully shaking up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.02g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L hydrochloric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, the blue color is faded, the solution is oscillated for 30 seconds again, and the solution is still colorless after being placed for 3 to 5 minutes, which shows that the hydrolysate is Fe 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 10 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: taking 10mL of 50 +/-5 ℃ brownish red hydrolysate into a transparent tube, adding 1g of iodoacetic acid and 1g of iodoacetamide, and fully shaking up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.02g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L hydrochloric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, the blue color is faded, the solution is oscillated for 30 seconds again, and the solution is still colorless after being placed for 3 to 5 minutes, which shows that the hydrolysate is Fe 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 11 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: taking 10mL of brownish red hydrolysate at 50 +/-5 ℃ into a transparent tube, adding 2g of iodoacetamide, and fully shaking up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.1g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L hydrochloric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, the blue color is faded, the solution is oscillated for 30 seconds again, and the solution is still colorless after being placed for 3 to 5 minutes, which shows that the hydrolysate is Fe 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 12 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: taking 10mL of brownish red hydrolysate at 50 +/-5 ℃ into a transparent tube, adding 1g of iodoacetic acid and 1g of iodoacetamide, and fully shaking up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.1g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L hydrochloric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, the blue color is faded, the solution is oscillated for 30 seconds again, and the solution is still colorless after being placed for 3 to 5 minutes, which shows that the hydrolysate is Fe 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 13 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: 10mL of brownish red hydrolysate at the temperature of 60 +/-5 ℃ is taken to be put into a transparent tube, 2g of iodoacetamide is added, and the mixture is fully shaken up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.02g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L hydrochloric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, the blue color is faded, the solution is oscillated for 30 seconds again, and the solution is still colorless after being placed for 3 to 5 minutes, which shows that the hydrolysate is Fe 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
Example 14 determination of whether the iron ion content of the hydrolysate is out of limits
S1, pretreatment: 10mL of brownish red hydrolysate at 70 +/-5 ℃ is taken to be put into a transparent tube, 2g of iodoacetamide is added, and the mixture is fully shaken up to obtain colorless pretreatment liquid. Wherein, the content of amino acid in the hydrolysate is 0.02g/mL.
S2, judging a result:
s2-1, adding 1mL of 6mol/L hydrochloric acid, and shaking up;
s2-2, adding 2mL of prepared starch indicating liquid, wherein the hydrolysate is blue;
s2-3, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and shaking up for 30 seconds;
s2-4, fading blue, oscillating the solution for 30 seconds, standing for 3-5 min, and showing that the hydrolysate is colorless 2+ And/or Fe 3+ The ion concentration meets the preparation requirement of the hydrolysate.
The results of the examples 2 to 14 show that after the iodo-compound containing acetyl is added, the hydrolysate is changed from brownish red to colorless, and the color of the end point does not return after the hydrolysate is placed for 3 to 5min, so that the method is accurate and stable. In addition, examples 2, 13 and 14 show that the temperature does not affect the measurement results of the present invention.
Comparative example 1 conventional iodometry was used to determine whether the iron ion content of the hydrolysate exceeded the limit
Taking 10mL of 50 +/-5 ℃ brownish red hydrolysate of the same batch (the content of amino acid is 0.02 g/mL), adding 1mL of 6mol/L hydrochloric acid into a transparent tube, shaking uniformly, adding 2g of potassium iodide powder, shaking uniformly, adding 2mL of prepared starch indicating solution, enabling the hydrolysate to show blue, adding 8mL of 0.001mol/L sodium thiosulfate standard solution, and repeatedly appearing the blue of a solution system between fading and returning blue in the shaking uniformly process, wherein the end point cannot be accurately judged.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such modifications are intended to be included in the scope of the present invention.
Claims (7)
1. A method for rapidly judging whether the content of iron ions in intermediate product hydrolysate exceeds the limit in the preparation process of qingkailing series products is characterized by comprising the following steps:
s1, pretreatment: adding iodo compound containing acetyl into the hydrolysate, and shaking up to obtain pretreatment solution;
s2, judging a result:
s2-1, adding an acid solution into the pretreatment solution, and shaking up;
s2-2, adding a starch indicating solution, and shaking up to make the solution system blue;
s2-3, adding a sodium thiosulfate standard solution, shaking up, converting the dosage of the sodium thiosulfate standard solution according to the iron ion content standard and a stoichiometric theory, and obtaining the formula as follows:
in the formula: v 1 The volume of the standard solution of sodium thiosulfate is mL;
C 1 the concentration is the concentration of a sodium thiosulfate standard solution, mol/L;
C 2 the content of iron ions in the hydrolysate is g/mL;
V 2 is the volume of the hydrolysate, mL;
s2-4, judging whether the content of iron ions exceeds the limit:
when the blue color of the solution system is faded, the content of iron ions is judged to be qualified;
when the blue color of the solution system is not faded, the content of the iron ions is judged to be out of limit;
the hydrolysate is prepared by hydrolyzing cornu Bubali powder and/or Concha Margarit powder with concentrated sulfuric acid, and adding Ca (OH) 2 Precipitating and filtering to obtain the product.
2. The method according to claim 1, wherein in step S1, the mass volume ratio of the iodo compound containing acetyl group to the hydrolysate is 0.2 to 1 g.
3. The method according to claim 2, wherein in step S1, the amino acid content in the hydrolysate is 0.01 to 0.1g/mL.
4. The method according to claim 1, wherein in step S2-1, the volume ratio of the acidic solution to the pretreatment solution is from 0.1 to 1.
5. The method according to claim 1, wherein in step S2-1, the concentration of the acidic solution is 0.01 to 6.0mol/L.
6. The method according to claim 1, wherein in step S2-1, the acidic solution is sulfuric acid, hydrochloric acid, nitric acid, acetic acid, potassium dihydrogen phosphate and/or sodium dihydrogen phosphate.
7. The method of claim 1, wherein in step S2-3, the concentration of the standard solution of sodium thiosulfate is 0.001-0.01 mol/L.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110667741.5A CN113406069B (en) | 2021-06-16 | 2021-06-16 | Method for detecting iron ions in hydrolysate prepared from cornu bubali powder and application of method in qingkailing hydrolysate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110667741.5A CN113406069B (en) | 2021-06-16 | 2021-06-16 | Method for detecting iron ions in hydrolysate prepared from cornu bubali powder and application of method in qingkailing hydrolysate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113406069A CN113406069A (en) | 2021-09-17 |
| CN113406069B true CN113406069B (en) | 2022-10-28 |
Family
ID=77684500
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110667741.5A Active CN113406069B (en) | 2021-06-16 | 2021-06-16 | Method for detecting iron ions in hydrolysate prepared from cornu bubali powder and application of method in qingkailing hydrolysate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113406069B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0579202A1 (en) * | 1992-07-15 | 1994-01-19 | Johnson & Johnson Clinical Diagnostics, Inc. | Sulfhydryl-complexing agents in clinical test elements |
| CN109078023A (en) * | 2018-09-17 | 2018-12-25 | 南京中医药大学 | A kind of cutin class effective ingredient in Chinese and the preparation method and application thereof |
-
2021
- 2021-06-16 CN CN202110667741.5A patent/CN113406069B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0579202A1 (en) * | 1992-07-15 | 1994-01-19 | Johnson & Johnson Clinical Diagnostics, Inc. | Sulfhydryl-complexing agents in clinical test elements |
| CN109078023A (en) * | 2018-09-17 | 2018-12-25 | 南京中医药大学 | A kind of cutin class effective ingredient in Chinese and the preparation method and application thereof |
Non-Patent Citations (3)
| Title |
|---|
| Kinetic and Equilibrium Studies of the Reactions of Cysteine and Penicillamine with Aqueous Iron(III);M. J. Sisley，et al.;《Inorg. Chem.》;19951231;第34卷(第24期);第6015-6023页 * |
| 核壳型Fe_3O_4@PDA@Au纳米材料对水牛角含巯基肽类成分的富集研究;刘婷 等;《南京中医药大学学报》;20200531;第36卷(第03期);第396-400页 * |
| 氧化还原间接碘量法测定铁强化营养盐中铁的试验方法研究;李翠英;《中国井矿盐》;20110731;第42卷(第4期);第34-35页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113406069A (en) | 2021-09-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101349648B (en) | Method for measuring trace elements in high titanium high boiler slag | |
| CN106290334B (en) | The chemistry in detecting of cobalt and manganese content in cobalt manganese raw material | |
| CN109799217A (en) | A kind of highly sensitive ratio fluorescent probe and its preparation method and application based on cadmium telluride quantum dot Yu europium ion compound system | |
| CN104164473A (en) | Glycated albumin enzymatic detection kit and detection method thereof | |
| CN103512855B (en) | The detection method of reduced glutathione | |
| CN108896750B (en) | Preparation method and application of BSA-Au/Ag NCs/OPD/HRP proportional type fluorescence sensor | |
| CN113406069B (en) | Method for detecting iron ions in hydrolysate prepared from cornu bubali powder and application of method in qingkailing hydrolysate | |
| CN104133035B (en) | A kind of minusing measures the method for magnesium metal content in briquetting modulizer | |
| CN109633079A (en) | A method of vanadium and ammonium content in detection metavanadate solution | |
| Luke et al. | Photometric determination of beryllium in beryllium-copper alloys | |
| Bambach | Polarographic determination of arsenic in biological material | |
| CN102539352B (en) | Determination method of cyanogen in thiocyanate | |
| CN111443085A (en) | Method for rapidly detecting content of water-soluble chloride in feed | |
| Fang et al. | Chemiluminescent sensor for hydrogen sulfide in rat brain microdialysis based on target-induced horseradish peroxidase deactivation | |
| Xiong et al. | Simple multimodal detection of selenium in water and vegetable samples by a catalytic chromogenic method | |
| CN103823017A (en) | Method for accurate measurement on nitric acid content of chemical corrosion solution for titanium alloy | |
| CN110850026B (en) | Method for analyzing COD (chemical oxygen demand) of high-chloride acidic uranium solution | |
| CN110672786A (en) | Method for rapidly detecting COD (chemical oxygen demand) in industrial wastewater | |
| Gan et al. | A Kit for Colorimetric VC Detection Combining with Bionic E-eye | |
| CN109696519B (en) | Method for testing oxidation reduction degree of graphene oxide | |
| US3404069A (en) | Method for measuring the glucose content of blood serum | |
| CN108088823B (en) | Method for detecting calcium content in dairy product | |
| CN107064483A (en) | A kind of double item rapid assay methods of serum urea nitrogen creatinine | |
| Belcher et al. | The determination of small amounts of hydroquinone | |
| Cartledge et al. | Determination of Cobalt as Trioxalatocobaltiate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |