Method for analyzing and detecting content of gelatin in electrolyte

Abstract

The invention discloses a method for analyzing and detecting the content of gelatin in an electrolyte, and relates to the technical field of analysis and determination of the content of gelatin, and the method comprises the following steps: 1, preparing sample gelatin solutions with different concentrations, and testing absorbance; 2, preparing a reagent solution required by detection; the method comprises the following steps: 1, preparing a reagent solution, taking 1-2mL of sample gelatin solutions with different concentrations, adding 2-3mL of the prepared reagent solution, measuring the absorbance of the corresponding concentration at 595nm by using a spectrophotometer, and drawing a standard curve according to the absorbance values under different concentrations, and 2, analyzing and detecting the content of gelatin in the electrolyte, namely taking 1-2mL of a sample with unknown gelatin concentration, 2-3 mL of a prepared test solution is added, the absorbance value of the sample is measured, according to the standard curve drawn in the second step, the absorbance value is substituted, the gelatin concentration under the corresponding absorbance can be calculated, and then the content of gelatin in the electrolyte is determined. The method is simple to operate, and realizes rapid analysis of the content in the industrial gelatin.

Description

Technical Field

[0001] The invention relates to the technical field of analysis and determination of gelatin content, in particular to an analysis and detection method for gelatin content in an electrolyte. Background Art

[0002] Gelatin is a macromolecular hydrophilic colloid and a product of partial hydrolysis of collagen. Collagen is composed of a relatively conservative sequence of tripeptides of glycine and two other amino acids, and contains a large proportion of hydroxyproline, proline and leucine, and contains the unique amino acid hydroxylysine. Depending on the use, the quality requirements for gelatin are different. When used as a binder, the main requirement is bonding strength. When used in photography, food, medicine and other fields, the purity of the product is emphasized. Gelatin is a polydisperse system with a certain molecular weight distribution. Its molecular weight distribution varies due to different process conditions and affects the physical and chemical properties of gelatin. Therefore, it is necessary to detect and measure the gelatin concentration in the electrolyte. Summary of the invention

[0003] The present invention provides a method for analyzing and detecting the gelatin content in an electrolyte, which solves the problems raised by the above-mentioned background technology.

[0004] To achieve the above object, the present invention is implemented by the following technical scheme: a method for analyzing and detecting the gelatin content in an electrolyte, comprising the following steps:

[0005] Step 1: First, prepare gelatin solutions of different concentrations;

[0006] Step 2: Prepare the test solution required for detection: Take 10-25 mg of Coomassie Brilliant Blue, dissolve it in 5-25 mL of 95% alcohol, then add 5-20 mL of 85% phosphoric acid, dilute it to 100-200 mL with water, filter it and set aside;

[0007] Step 3: Take 1-2 mL of the gelatin sample prepared in step 1, add 2-3 mL of the test solution prepared in step 2, mix thoroughly, and react at room temperature for 5-15 minutes. Use a spectrophotometer to scan the UV absorption spectrum and record the absorbance values ​​corresponding to gelatin samples of different concentrations at 595 nm.

[0008] Step 4: Draw a standard curve with gelatin concentration as the horizontal axis and absorbance value as the vertical axis;

[0009] Step 5: Take 3-5 mL of the sample to be tested containing gelatin in the electrolyte, remove the copper ions therein, and set aside;

[0010] Step 6: Take 1 mL of the electrolyte sample prepared in step 5 and add it to the test solution prepared in step 2. Use a spectrophotometer to measure the absorbance value at the corresponding wavelength of 595 nm, and substitute it into the standard curve to calculate the gelatin content in the unknown sample.

[0011] Preferably, the specific preparation method of gelatin solutions with different concentrations in Step 1 is as follows:

[0012] Take 60 mg of gelatin, add it to a 50 mL sample tube, add water, and dissolve it completely by ultrasonic treatment to prepare a stock solution with a concentration of 2000 μg / mL. Then dilute it to standard samples with concentrations of 10 μg / mL, 20 μg / mL, 40 μg / mL, 60 μg / mL, 80 μg / mL, 100 μg / mL, 200 μg / mL, 300 μg / mL, 400 μg / mL, 600 μg / mL, 800 μg / mL, and 1000 μg / mL respectively.

[0013] Preferably, for the reagent solution specifically prepared in Step 2, first weigh 20 mg of Coomassie Brilliant Blue, dissolve it in 5 mL of alcohol (95%), then add 5 mL of phosphoric acid (85%), dilute it to 100 mL with water, and filter for standby.

[0014] Preferably, to remove copper ions in Step 3, fill an adsorption resin in a chromatography column, and use the adsorption resin to adsorb copper ions in the electrolyte until the solution becomes clear, then set it aside for standby.

[0015] Preferably, the test reagent is Coomassie Brilliant Blue G-250.

[0016] The present invention has the following beneficial effects:

[0017] 1. For the analysis and detection method of the gelatin content in this electrolyte, by plotting a standard curve graph, according to the curve relationship, the gelatin concentration corresponding to the absorbance can be calculated, and then the analysis and detection of the gelatin content in the electrolyte can be realized. Moreover, according to the corresponding curve relationship, the gelatin concentration content can be known. This method is simple to operate and realizes the rapid analysis of the content in industrial gelatin. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is the standard curve graph of the present invention;

[0019] Figure 2 is the ultraviolet absorption spectrum diagram of the standard solution of the present invention;

[0020] Figure 3 is the ultraviolet graph for the determination of gelatin in the actual electrolyte after removing copper ions of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] Please refer to the accompanying drawings of the specification. The present invention provides a technical solution: an analysis and detection method for the gelatin content in an electrolyte, including the following steps:

[0023] Step 1: First, prepare gelatin solutions with different concentrations;

[0024] Step 2: Prepare the test solution required for detection: Take 10 - 15 mg of Coomassie Brilliant Blue, dissolve it in 10 - 25 mL of 95% alcohol, then add 5 - 20 mL of 85% phosphoric acid, dilute it with water to 100 - 200 mL, and filter for standby;

[0025] Step 3: Take 1 - 2 mL of the gelatin sample in Step 1, add 2 - 3 mL of the test solution prepared in Step 2, mix well, and react at room temperature for 5 - 15 min. Use a UV - visible spectrophotometer to scan the UV absorption spectrum, and record the absorbance values corresponding to different concentrations of gelatin samples at 595 nm;

[0026] Step 4: Draw a standard curve with the gelatin concentration as the abscissa and the absorbance value as the ordinate;

[0027] Step 5: Take 3 - 5 mL of the test sample with gelatin in the electrolyte, remove the copper ions therein, and set aside for use;

[0028] Step 6: Take 1 mL of the electrolyte sample in Step 5 above and add it to the test solution prepared in Step 2. Use a UV - visible spectrophotometer to measure the absorbance value at 595 nm corresponding to the wavelength, and substitute it into the standard curve to calculate the gelatin content in the unknown sample;

[0029] The UV absorption spectrum of the standard solution is as Figure 2 shown. At a wavelength of 595 nm, the absorbance values of different concentrations of added gelatin are recorded as follows:

[0030] Concentration (μg / mL) Absorbance Abs 10 1.328 20 1.341 40 1.45 60 1.552 80 1.732 100 1.92 200 2.163 300 2.238 400 2.284 600 2.325 800 2.327

[0031] Based on the above data, the standard curve is drawn as Figure 1 shown.

[0032] The specific measurement results of the data samples are as follows:

[0033] S1: Abs = 1.55, substituting into the standard curve gives a concentration of 51.5 μg / mL.

[0034] S2: Abs = 1.875. Substituting it into the standard curve gives a concentration of 100.7 μg / mL.

[0035] S3: Abs = 1.366. Substituting it into the standard curve gives a concentration of 23.6 μg / mL.

[0036] S4: Abs = 1.403. Substituting it into the standard curve gives a concentration of 29.24 μg / mL.

[0037] S5: Abs = 1.381. Substituting it into the standard curve gives a concentration of 25.9 μg / mL.

[0038] The specific preparation method of the gelatin solutions with different concentrations in Step 1 is as follows: Take 30 mg of gelatin, add it into a 50 mL sample tube, add 30 mL of water, and dissolve it completely by ultrasonic treatment to prepare a stock solution with a concentration of 1000 μg / mL. Then dilute it to standard samples with concentrations of 10 μg / mL, 20 μg / mL, 40 μg / mL, 60 μg / mL, 80 μg / mL, 100 μg / mL, 200 μg / mL, 300 μg / mL, 400 μg / mL, 600 μg / mL, and 800 μg / mL respectively.

[0039] The specific reagent solution prepared in Step 2: First, weigh 10 mg of Coomassie Brilliant Blue, dissolve it in 5 mL of alcohol (95%), then add 10 mL of phosphoric acid (85%), dilute it to 100 mL with water, and filter for standby.

[0040] To remove copper ions in Step 5, fill the chromatographic column with adsorption resin, and use the adsorption resin to adsorb copper ions in the electrolyte until the solution becomes clear, and then set it aside for use.

[0041] Operation process: Use a cation resin for adsorbing Cu, load the column and pre-treat it (after dry loading the column, soak it with water), and let the residual water in the resin column flow out. Take 30 mL of electrolyte, add it to the column head, and soak for about 5 min. Open the valve, let the solution drip until the color is close to colorless. Record the volume obtained after 30 mL has flowed out, and then add 2 - 3 mL of water to wash the gelatin that may remain in the column. Measure the gelatin content as described above, and pay attention to converting the concentration in the original solution. The resin in the column is soaked with dilute hydrochloric acid for a certain period of time, and it can be found that the resin returns to its original color. Collect the dilute hydrochloric acid for future use. The resin can be recycled by washing it with water (or washing it with water after neutralizing with NaOH solution until it is neutral).

[0042] After the copper ions are adsorbed and removed by the resin material, take 1 mL of the clarified solution after passing through the column, add 2 mL of Coomassie Brilliant Blue, which shows blue color. Measure the UV / Vis, and the absorbance Abs at 595 nm is 1.207. Take the blank solution after passing through the column without adding Coomassie Brilliant Blue and directly measure the UV / Vis. Its peak position is approximately at 390 nm, corresponding to the ultraviolet absorption wavelength of copper sulfate. And the absorbance Abs of the instrument at 595 nm is 0.059. After deducting the influence of the solution, the absorbance Abs of the sample at 595 nm is 1.148. Substitute it into the standard curve to obtain the ultraviolet diagram for the determination of gelatin in the actual electrolyte as shown in Figure 3 shown.

[0043] For the analysis and detection method of the gelatin content in this electrolyte, when in use,

[0044] S1: Take 30 mg of gelatin, add it into a 50 mL sample tube, add 30 mL of hot water, and dissolve it completely by ultrasonic wave to prepare a stock solution with a concentration of 1000 μg / mL. Dilute it into standard samples with concentrations of 10 μg / mL, 20 μg / mL, 40 μg / mL, 60 μg / mL, 80 μg / mL, 100 μg / mL, 200 μg / mL, 300 μg / mL, 400 μg / mL, 600 μg / mL, and 800 μg / mL respectively;

[0045] S2: Weigh 10 mg of Coomassie Brilliant Blue G-250, dissolve it in 5 mL of alcohol (95%), then add 10 mL of phosphoric acid (85%), dilute it to 100 mL with water, and filter for standby;

[0046] S3: Take 1 mL of standard samples with different concentrations respectively, add 2 mL of Coomassie Brilliant Blue to each of them, shake well, and measure the absorbance at 595 nm corresponding to the concentration by ultraviolet. Draw a standard curve according to the absorbance values at different concentrations;

[0047] S4: Take 3 - 5 mL of the electrolyte, fill an appropriate amount of adsorption resin in the chromatography column, use the adsorption resin to adsorb the copper ions in the electrolyte, and adsorb until the solution is clarified as much as possible for standby;

[0048] S5: Take 1 mL of the electrolyte sample after removing copper ions, add 2 mL of Coomassie Brilliant Blue, shake well, measure the absorbance at 595 nm corresponding to the concentration by ultraviolet, and substitute it into the standard curve to calculate the concentration value;

[0049] S6: According to the measured data:

[0050] The specific measurement results of the data samples are as follows:

[0051] S1: Abs = 1.55, substitute it into the standard curve to obtain a concentration of 51.5 μg / mL.

[0052] S2: Abs = 1.875. Substituting it into the standard curve gives a concentration of 100.7 μg / mL.

[0053] S3: Abs = 1.366. Substituting it into the standard curve gives a concentration of 23.6 μg / mL.

[0054] S4: Abs = 1.403. Substituting it into the standard curve gives a concentration of 29.24 μg / mL.

[0055] S5: Abs = 1.381. Substituting it into the standard curve gives a concentration of 25.9 μg / mL.

Claims

1. A method for analyzing and detecting gelatin content in an electrolyte, characterized in that: The following steps are involved: Step 1: First, prepare gelatin solutions of different concentrations; Step 2: Prepare the test solution required for detection: Take 10-25 mg of Coomassie Brilliant Blue, dissolve it in 5-25 mL of 95% alcohol, then add 5-20 mL of 85% phosphoric acid, dilute it with water to 100-200 mL, filter it and set aside; Step 3: Take 1-2 mL of the gelatin sample prepared in step 1, add 2-3 mL of the test solution prepared in step 2, mix thoroughly, and react at room temperature for 5-15 minutes. Use a spectrophotometer to scan the absorption spectrum and record the absorbance values ​​corresponding to gelatin samples of different concentrations at 595 nm. Step 4: Draw a standard curve with gelatin concentration as the horizontal axis and absorbance value as the vertical axis; Step 5: Take 3-5 mL of the sample to be tested containing gelatin in the electrolyte, remove the copper ions therein, and set aside; Step 6: Take 2-3 mL of the electrolyte sample prepared in step 5 above and add it to the test solution prepared in step 2. Use a spectrophotometer to measure the absorbance value at the corresponding wavelength of 595 nm, and substitute it into the standard curve to calculate the gelatin content in the unknown sample.

2. The method for analyzing and detecting gelatin content in an electrolyte according to claim 1, characterized in that: The specific preparation method of gelatin solutions of different concentrations in step 1 is as follows: Take 60 mg of gelatin, add it to a 50 mL sample tube, add 30 mL of water, and sonicate to dissolve it completely to make a mother solution with a concentration of 2000 μg / mL, and dilute it into standard samples with concentrations of 10 μg / mL, 20 μg / mL, 40 μg / mL, 60 μg / mL, 80 μg / mL, 100 μg / mL, 200 μg / mL, 300 μg / mL, 400 μg / mL, 600 μg / mL, 800 μg / mL, and 1000 μg / mL, respectively.

3. The method for analyzing and detecting gelatin content in an electrolyte according to claim 1, characterized in that: The test solution prepared in step 2 is firstly weighed 20 mg of Coomassie Brilliant Blue, dissolved in 10 mL of 95% alcohol, then added with 10 mL of 85% phosphoric acid, diluted with water to 100 mL, and filtered for later use.

4. The method for analyzing and detecting gelatin content in an electrolyte according to claim 1, characterized in that: In the step 5, the copper ions are removed by filling an adsorption resin in a chromatography column, and the adsorption resin is used to adsorb the copper ions in the electrolyte until the solution is clarified and set aside.

5. The method for analyzing and detecting gelatin content in an electrolyte according to claim 3, characterized in that: The test reagent is Coomassie Brilliant Blue G-250.

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