CN-121978321-A - Quantitative analysis method for hydrogen peroxide in wooden relics

CN121978321ACN 121978321 ACN121978321 ACN 121978321ACN-121978321-A

Abstract

The application discloses a quantitative analysis method of hydrogen peroxide in wooden relics, and relates to the fields of wooden relics protection, analysis and detection. The method comprises the steps of dividing a wood relic sample to be detected into a plurality of aliquots, carrying out differential pretreatment on the different aliquots to enable contribution of endogenous hydrogen peroxide and/or interfering substances in each sample to a final detection signal to be in a computable difference, respectively extracting hydrogen peroxide from each pretreated aliquot to obtain corresponding extracting solutions, respectively measuring apparent content of the hydrogen peroxide in each extracting solution, and calculating real content of the endogenous hydrogen peroxide in the wood relic sample based on the measured difference between the apparent contents. The quantitative analysis method of hydrogen peroxide in the wooden relics can effectively overcome the complex matrix interference of the wooden relics, is simple and convenient to operate, is accurate in quantification, does not need complex pretreatment, and meets the cultural relic protection requirements.

Inventors

WANG FENGJIAO
Mou lei
WANG CHONG
WANG YALI
JIANG RUXIAO
DING MENG
ZHANG HUINI

Assignees

四川省文物考古研究院(三星堆研究院、四川石窟寺保护研究院)

Dates

Publication Date: 20260505
Application Date: 20260407

Claims (10)

1. The quantitative analysis method of the hydrogen peroxide in the wooden relics is characterized by comprising the following steps of: dividing a wood relic sample to be detected into a plurality of aliquots; By differential pretreatment of different aliquots, the contribution of endogenous hydrogen peroxide and/or interfering substances in each sample to the final detection signal is given a computable difference; extracting hydrogen peroxide from each pretreated aliquot respectively to obtain corresponding extracting solution; and calculating the actual content of the endogenous hydrogen peroxide in each extracting solution based on the difference between the detected apparent contents.
2. The method for quantitatively analyzing hydrogen peroxide in a wooden relic according to claim 1, wherein the pretreatment comprises: taking two aliquots of a wood cultural relic sample to be detected, namely a first aliquot and a second aliquot, respectively, soaking the two aliquots in water respectively to enable the two aliquots to be fully soaked; adding a hydrogen peroxide decomposer to the soak solution soaked with the first aliquot, and contacting the first aliquot with the hydrogen peroxide decomposer to selectively remove endogenous hydrogen peroxide; The soaked second aliquot was not subjected to any treatment; Wherein the true content of the endogenous hydrogen peroxide is calculated by the following formula (1): ΔC=C Original, original -C Decomposition of (1); Wherein C Original, original is the apparent content measured on the second aliquot without any treatment and C Decomposition of is the apparent content measured on the first aliquot treated with the hydrogen peroxide decomposer.
3. The method for quantitatively analyzing hydrogen peroxide in a wooden relic according to claim 2, wherein the mass ratio of the aliquot to the water is 1:5 to 1:15; and/or, after adding the hydrogen peroxide decomposer to the soaking solution soaked with the first aliquot, standing at a low temperature for 24 hours to 72 hours; And/or the hydrogen peroxide decomposer is a catalase solution with the enzyme activity of 1000U/mL to 5000U/mL.
4. The method for quantitatively analyzing hydrogen peroxide in a wooden relic according to claim 1, wherein the pretreatment comprises: taking two aliquots of a wood cultural relic sample to be detected, namely a first aliquot and a second aliquot, respectively, soaking the two aliquots in water respectively to enable the two aliquots to be fully soaked; adding an interfering substance shielding agent to the soaking solution in which the first aliquot is soaked, and enabling the first aliquot to be in contact with the interfering substance shielding agent so as to selectively shield the influence of the interfering substance on the measurement of the hydrogen peroxide; adding a hydrogen peroxide decomposer and an interfering substance shielding agent to the soaking solution in which the second aliquot is soaked, so that the second aliquot is simultaneously contacted with the hydrogen peroxide decomposer and the interfering substance shielding agent; wherein the true content of the endogenous hydrogen peroxide is calculated by the following formula (2): ΔC Endogenous sources =C Shielding -C Combination of (2); Wherein C Shielding is the apparent content measured for the first aliquot treated with the interfering substance masking agent and C Combination of is the apparent content measured for the second aliquot treated with the combination of the hydrogen peroxide decomposer and the interfering substance masking agent.
5. The method for quantitatively analyzing hydrogen peroxide in a wooden relic according to claim 4, wherein the mass ratio of the aliquot to water is 1:5 to 1:15; and/or, after adding the hydrogen peroxide decomposer to the soaking solution soaked with the first aliquot, standing at a low temperature for 24 hours to 72 hours; and/or, after adding the hydrogen peroxide decomposer and the interfering substance shielding agent to the soaking solution soaked with the second aliquot, standing at a low temperature for 24 hours to 72 hours; And/or the interfering substance shielding agent is disodium ethylenediamine tetraacetate solution with the concentration of 0.05mol/L to 0.2 mol/L; And/or the hydrogen peroxide decomposer is a catalase solution with the enzyme activity of 1000U/mL to 5000U/mL.
6. The method for quantitatively analyzing hydrogen peroxide in a wooden relic according to claim 1, wherein the pretreatment comprises: taking four aliquots of the wood relic sample to be measured, namely a first aliquot, a second aliquot, a third aliquot and a fourth aliquot, respectively, soaking the four aliquots in water respectively, and fully soaking the four aliquots; adding a hydrogen peroxide decomposer to the soak solution soaked with the first aliquot, and contacting the first aliquot with the hydrogen peroxide decomposer to selectively remove endogenous hydrogen peroxide; Adding an interfering substance shielding agent to the soak solution soaked with the second aliquot, and contacting the second aliquot with the interfering substance shielding agent to selectively shield the interfering substance from the hydrogen peroxide assay; Adding a hydrogen peroxide decomposer and an interfering substance shielding agent to the soaking solution in which the third aliquot is soaked, and enabling the third aliquot to be simultaneously contacted with the hydrogen peroxide decomposer and the interfering substance shielding agent so as to selectively remove endogenous hydrogen peroxide and selectively shield the influence of the interfering substance on the hydrogen peroxide measurement; the soaked fourth aliquot was not subjected to any treatment; by comparing the apparent contents measured in the above treatment mode, the true content of endogenous hydrogen peroxide is calculated and the influence of interfering substances is evaluated, wherein: The true content of endogenous hydrogen peroxide is calculated by the following formula (3) or formula (4): ΔC Endogenous sources =C Original, original -C Decomposition of (3); ΔC Endogenous sources =C Shielding -C Combination of (4); the apparent content caused by the interfering substance is calculated by the following formula (5) or formula (6): ΔC Interference (I) =C Original, original -C Shielding (5); ΔC Interference (I) =C Decomposition of -C Combination of (6); Wherein C Shielding is the apparent content measured on the second aliquot treated with the interfering substance masking agent, C Combination of is the apparent content measured on the third aliquot treated with the combination of the hydrogen peroxide decomposer and the interfering substance masking agent, C Decomposition of is the apparent content measured on the first aliquot treated with the hydrogen peroxide decomposer, and C Original, original is the apparent content measured on the fourth aliquot without any treatment.
7. The method for quantitatively analyzing hydrogen peroxide in a wooden relic according to claim 6, wherein the mass ratio of the aliquot to water is 1:5 to 1:15; and/or, after adding the hydrogen peroxide decomposer to the soaking solution soaked with the first aliquot, standing at a low temperature for 24 hours to 72 hours; and/or, adding an interfering substance shielding agent to the soaking solution soaked with the second aliquot, and standing at a low temperature for 24 to 72 hours; and/or, adding a hydrogen peroxide decomposer and an interfering substance shielding agent to the soaking solution soaked with the third aliquot, and standing at a low temperature for 24 to 72 hours; And/or the hydrogen peroxide decomposer is a catalase solution with the enzyme activity of 1000U/mL to 5000U/mL; And/or the interfering substance shielding agent is an ethylene diamine tetraacetic acid disodium solution with the concentration of 0.05mol/L to 0.2 mol/L.
8. The method for quantitatively analyzing hydrogen peroxide in wooden relics according to claim 4 or 6, wherein the method further comprises pre-inspecting the aliquots before the differential pretreatment, detecting the total iron content of the aliquots, adding the interfering substance shielding agent in batches at intervals of 4 to 12 hours according to the total iron content obtained by the pre-inspecting when the differential pretreatment is performed on different aliquots, wherein the total amount of the interfering substance shielding agent is 1.1 to 2 times the theoretical required amount for removing iron; And/or, the hydrogen peroxide decomposer is added in batches at intervals of 4 hours to 12 hours, and before each addition of the hydrogen peroxide decomposer, detecting whether the hydrogen peroxide in the aliquot is completely reacted to determine whether further addition is required.
9. The quantitative analysis method of hydrogen peroxide in wooden relics according to claim 1, wherein the determination of the apparent content of hydrogen peroxide in each extracting solution is performed by photometry, fluorescence spectrometry, chemiluminescence or electrochemical analysis, and when the determination of the apparent content of hydrogen peroxide in each extracting solution is performed by photometry, the method comprises the following steps: Preparing hydrogen peroxide standard solutions with serial concentrations, adding a titanium salt color developing agent into each standard solution, enabling hydrogen peroxide to react with titanium salt to generate a hydrogen peroxide-titanium complex, centrifugally separating and precipitating, discarding supernatant, adding a precipitation dissolving agent, measuring absorbance at 415nm wavelength by taking a blank solution as a reference, and carrying out linear regression by taking the hydrogen peroxide concentration as an abscissa and the absorbance as an ordinate to obtain a standard curve equation; Adding a titanium salt color developing agent into the extracting solution to be detected, enabling hydrogen peroxide and titanium salt to react to generate a hydrogen peroxide-titanium complex, centrifugally separating and precipitating, discarding supernatant, adding a precipitation dissolving agent, and measuring absorbance at 415nm wavelength by taking a blank solution as a reference; and calculating the content, namely substituting the measured absorbance of the sample into the standard curve equation, and calculating the apparent content of the hydrogen peroxide in the extracting solution.
10. The method for quantitatively analyzing hydrogen peroxide in wooden relics according to claim 1, further comprising the step of labeling and recovering the wooden relics with known hydrogen peroxide content, wherein a known amount of hydrogen peroxide standard is added to the wooden relics with known hydrogen peroxide content, and then the method according to claim 1 is used for measuring, and calculating the recovery rate to evaluate the accuracy of the quantitative analysis method.

Description

Quantitative analysis method for hydrogen peroxide in wooden relics Technical Field The application relates to the field of protection, analysis and detection of wooden relics, in particular to a quantitative analysis method of hydrogen peroxide in wooden relics. Background Wooden relics are important components of human cultural heritage and bear precious historic, artistic and scientific values. However, in the long-term preservation process, the wooden cultural relics are easy to oxidize and age due to environmental factors (such as illumination, temperature and humidity change, metal pollutants and the like), so that the materials are degraded and the strength is reduced, and the permanent preservation of the wooden cultural relics is seriously threatened. The hydrogen peroxide is used as a key intermediate product of lignocellulose photooxidation and Fenton reaction catalyzed by metal ions, and the accurate measurement of the content of the hydrogen peroxide has important significance for evaluating the degradation degree of cultural relics, revealing degradation mechanism and formulating scientific protection and repair strategies. Currently, the detection methods of hydrogen peroxide mainly include titration, chemiluminescence, fluorescence, ultraviolet-visible spectrophotometry, and the like. Among them, the titanium salt colorimetric method is widely adopted because of simple operation and high equipment popularity, and the principle is based on that hydrogen peroxide and titanium salt generate stable yellow complex in an acidic medium and have characteristic absorption at 415nm wavelength. However, the complexity of the wood relic matrix poses a serious challenge for accurate quantification of hydrogen peroxide. The method is characterized in that firstly, transition metal ions such as iron/ferrous iron and the like commonly existing in cultural relics possibly change the content of hydrogen peroxide of a target object by catalyzing Fenton reaction in the whole detection process to cause lower systematic measurement results, secondly, the metal ions possibly interfere the normal color development of a titanium salt color developing agent by competing complex reaction to influence detection sensitivity, and thirdly, organic components such as lignin, extractives and the like possibly generate nonspecific background absorption at characteristic absorption wavelength to cause higher false measurement results. The prior art is difficult to overcome the interference in the opposite direction at the same time, and the conventional blank correction or separation and purification method cannot effectively distinguish and deduct the complex matrix effect formed by superposition of multiple mechanisms, so that the accuracy of a detection result cannot be ensured. In view of the above problems, the prior art has focused on the detection of free hydrogen peroxide or employed cumbersome separation and purification steps in an attempt to eliminate substrate interference. For example, the target is separated in advance by a method such as solid phase extraction or column chromatography. However, these methods tend to be complex to operate, time consuming, and difficult to effectively distinguish and eliminate the specific matrix interference described above, and also tend to result in loss of target or introduction of new errors during the separation process. Therefore, the development of the hydrogen peroxide quantitative analysis method capable of specifically overcoming the complex matrix interference of the wooden relics, being simple and convenient to operate and accurate in result becomes a technical problem to be solved in the scientific research and protection practice of the wooden relics. Disclosure of Invention The application discloses a quantitative analysis method of hydrogen peroxide in wooden relics, which aims to solve the technical problems that in the prior art, the conventional method cannot effectively distinguish and eliminate interference, the accuracy of detection results is poor, and the conventional separation and purification method is complicated in operation and easy to cause target loss due to multiple matrix effects of metal ion catalytic target decomposition, competitive complexation interference color development, organic component background absorption superposition and the like existing in the detection of the wooden relics by virtue of a complex matrix. In order to solve the problems, the application adopts the following technical scheme: in a first aspect, an embodiment of the present application provides a method for quantitatively analyzing hydrogen peroxide in a wooden relic, including the steps of: dividing a wood relic sample to be detected into a plurality of aliquots; By differential pretreatment of different aliquots, the contribution of endogenous hydrogen peroxide and/or interfering substances in each sample to the final detection signal is given a computable differ