CN105158193B - Method for measuring substitution degree of hydroxypropyl chitosan - Google Patents
Method for measuring substitution degree of hydroxypropyl chitosan Download PDFInfo
- Publication number
- CN105158193B CN105158193B CN201510575806.8A CN201510575806A CN105158193B CN 105158193 B CN105158193 B CN 105158193B CN 201510575806 A CN201510575806 A CN 201510575806A CN 105158193 B CN105158193 B CN 105158193B
- Authority
- CN
- China
- Prior art keywords
- sample
- hydroxypropyl chitosan
- infrared absorption
- chitosan
- hydroxypropyl
- 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
Images
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention discloses a method for measuring the substitution degree of hydroxypropyl chitosan, which comprises the following steps: drying a hydroxypropyl chitosan sample. Establishing a detection model: a. obtaining an infrared absorption spectrogram of the sample by using an infrared absorption spectrometer; b. measuring 1460-1456cm characteristic methyl peak‑1With the whole waveform 1530-1215cm‑1The absorbance value A1 of the peak height of which the connecting line of the wave trough is a base line and the characteristic peak 1602-1596cm of amino group at the C2 position‑1The ratio X of the absorbance value A2 of the peak height taking the trough connecting line as the base line; c. measuring the substitution degree Y of the hydroxypropyl chitosan sample by a standard method; d. and establishing a linear model Y as kX + b by X to Y so as to obtain specific values of k and b in the model. Substituting the ratio X of the sample to be detected, which is obtained through the infrared absorption spectrogram, into the linear regression model, so as to obtain the substitution degree Y through calculation. The method is simple, convenient, quick and accurate, and does not need precise weighing and sample dissolution.
Description
Technical Field
The invention belongs to the field of research and application of detection methods of substitution degrees of hydroxypropyl chitosan, relates to a method for measuring substitution degrees of hydroxypropyl chitosan, and particularly relates to a method for measuring substitution degrees of hydroxypropyl chitosan by using an infrared absorption spectrometry.
Background
The chitosan has good biocompatibility, biodegradability, stability and safety, but the water solubility is poor, the chitosan can only be dissolved in an acidic medium, and the chitosan is subjected to hydroxypropylation to generate hydroxypropyl chitosan, so that the solubility of the hydroxypropyl chitosan can be improved, and the application field and the development process of the hydroxypropyl chitosan are greatly widened. It has been found that hydroxypropyl chitosan has wide application prospects in the fields of medicine, cosmetics, food, paper making, textile and the like (physicochemical properties of hydrogel, hemostatic function and hemostatic function of Song-type hydrogel, 65. 9. Biochemcial effect of chitosan, 2014. 9. Marine compatibility with chitosan 090. 9. Biochecal Journal of Biological Macromolecules 2014. 246. 1720. Dong Y. infilter. of Biological hydrogel. European Polymer Journal of Biological hydrogel, 1713. 1720. pharmaceutical and cosmetic film, 65. Biochecal effect of chitosan, antibacterial property, and adsorbability (Cheng Z. et al. Biochecal effects of chitosan, Biochecal chitosan, etc.; Biochecal effect of chitosan, 65. 9. Biochecal effect of chitosan, 65. Biochecal effect of chitosan, 2014. 090. 9. Biochecal effect of chitosan, 2014. 9. Pacific. Biochecal effect of chitosan, 2014. 9. Pacific effect of chitosan, 2007,37: 131-; tangxinfeng, hydroxypropyl chitosan preparation and its use as a neutral paper-making aid, master thesis of wuhan university, 2005; the preparation and performance of the jili HPCTS and its application in textile finishing, university of sichuan master paper, 2005; yuan birch and the like, preparation of hydroxypropyl chitosan, moisture absorption and retention research thereof, fine and special chemicals, 2005; zhang L, et al, effect of organic added hydrolyzed chips on the levels of iron, copper, zinc and calcium in semiconductor, international Journal of Biological Macromolecules, Volume 64, March 2014, Pages 25-29).
When finding that hydroxypropyl chitosan has such potential application value, relevant researchers must further study the influence of the substitution degree of hydroxypropyl on chitosan (the number of hydroxypropyl groups connected to each glucosamine and N-acetylglucosamine molecule in hydroxypropyl chitosan molecule) on the performance and application of hydroxypropyl chitosan, however, the research reports in this respect are not clear. Even though the literature reports that the hydroxypropyl chitosan biodegradability research with different degrees of substitution (2004,1:33-36) published in China Marine drugs only adopts a hydroxypropyl determination method in the second part of China pharmacopoeia, namely, an oxidation and alkali titration method, the substitution degree test result is not found. Foreign documents Effects of hydroxypropyl default on physicochemical activities of chitosan from liquids. International Journal of Biological Macromolecules,2014,65: 246-; dong Y, et al, in the invention of the grid of molar evaluation on crystalline liquid crystal, European Polymer Journal,2001,37(8): 1713-.
The methods for measuring the substitution degree of hydroxypropyl chitosan reported in the literature include element analysis (Zhang Yong, Zhang Kun. element analysis method for simultaneously measuring the substitution degree and water content of hydroxypropyl chitosan; analytical laboratories, 2014, 33 (8): 978-:
1846-: 201410841212.2).
Hydroxypropyl chitosan is generally a high molecular polymer, and different groups in and among molecules interact with each other in a complex manner, so that in the analysis method of nuclear magnetic resonance hydrogen spectra, errors are easily introduced by quantitatively calculating the number of hydrogen protons in the corresponding environment by using the relative absorption intensities of the hydrogen protons at different chemical displacement positions, and the accurate calculation of the substitution degree is obviously influenced. The element analysis method only uses the mass ratio of C to N in a sample, compares the measured value of H% with the calculated value, has single parameter and is not influenced by the degree of substitution of the sample and the moisture content, and therefore, the element analysis method is commonly used for reference and comparative study of other measuring methods of the degree of substitution. The two methods have high detection cost and are not suitable for large-batch conventional detection of hydroxypropyl chitosan production enterprises and research units.
The detection cost of the infrared absorption spectrometry is relatively low, a chitosan sample does not need to be precisely weighed and dissolved, the operation is simple, convenient and quick, and the method is particularly suitable for a handheld infrared spectrometer, so the method has great significance for quality control and application research and development of hydroxypropyl chitosan production enterprises, quick detection of quality inspection departments and scientific research of scientific research institutes.
However, research on hydroxypropyl chitosan is started from eighties at home and abroad, researchers generally use an infrared absorption spectrum as one of the methods for structural characterization, and no relevant report for determining the substitution degree of hydroxypropyl chitosan by using the method is found so far. On the one hand, the infrared spectrogram of the hydroxypropyl chitosan sample can be shown by 'observing autumn hair' through a trace amount of impurities, and the influence on the peak shape and the peak position change of a characteristic peak is directly influenced (Zhang Yong Dun, Zhang Kun. the influence of a separation and purification method on the measurement of the structure and the substitution degree of the hydroxypropyl chitosan. the university of Qingdao science and technology, 2015,36(3): 251-; on the other hand, hydroxypropylation itself makes it difficult to find a certain structural characteristic peak which is constant as a reference peak for calculation of the degree of substitution because the characteristic peaks overlap, deform, migrate, and the like. Therefore, in the premise of determining the characteristic methyl peak as the analysis peak, the integration method of finding a suitable reference peak and determining the two is also the key of the invention.
Disclosure of Invention
In order to solve the defects of the prior art, the invention firstly aims to provide a simple, convenient, rapid, accurate and low-cost method for detecting the substitution degree of hydroxypropyl chitosan.
The purpose of the invention is realized by the following technical scheme:
a method for measuring the substitution degree of hydroxypropyl chitosan is characterized by comprising the following steps:
the method comprises the steps of drying hydroxypropyl chitosan samples to remove water, wherein each hydroxypropyl chitosan sample is prepared through hydroxypropylation reaction and dealkalization purification, and is derived from chitosan with known deacetylation degree and/or chitosan with deacetylation degree not more than 3% different from that of raw material chitosan;
establishment of detection model
a. Obtaining infrared absorption spectrograms of hydroxypropyl chitosan samples with different degrees of substitution by using an infrared absorption spectrometer;
b. measuring 1460-1456cm characteristic methyl peak from the infrared absorption spectrogram of hydroxypropyl chitosan obtained in step a by using application software of an infrared absorption spectrometer-1With the whole waveform 1530-1215cm-1The trough of (a) is connected with the absorbance value of the peak height of the base line BL1Amino characteristic peaks 1602-1596cm at positions A1 and C2-1The ratio X of the absorbance value A2 with the trough connecting line as the peak height of the base line BL 2;
c. measuring the substitution degree Y of the hydroxypropyl chitosan sample in the step a by a standard method;
d. establishing a regression model with good linearity by using the ratio X obtained in the step b to the substitution degree Y of the hydroxypropyl chitosan sample obtained in the step c, namely Y is kX + b, so as to obtain specific values of k and b in the model;
the third step of detection: the method comprises the steps of obtaining an infrared absorption spectrogram of the hydroxypropyl chitosan sample to be detected according to the step a in the step b in the step two, obtaining a ratio X according to the step b in the step two, substituting the ratio X into the linear regression model in the step d in the step two, and obtaining the substitution degree Y of the hydroxypropyl chitosan sample to be detected through calculation.
Preferably, the hydroxypropyl chitosan sample is dried in an oven at 80 ℃ for 4-5 hours, then quickly heated to 105 ℃, dried for 1.5-2 hours, and taken out of a dryer filled with calcium oxide for later use.
Preferably, the infrared absorption spectrometer is a Fourier transform infrared spectrometer,
preferably, the detection conditions of the infrared absorption spectrometer are as follows: scanning range 4000--1Scanning is carried out 16-32 times, and the resolution is 4cm < -1 >.
Preferably, background detection is performed prior to said testing of hydroxypropyl chitosan samples using infrared absorption spectroscopy.
Preferably, the infrared absorption spectrogram of the hydroxypropyl chitosan sample is subjected to background deduction treatment.
Preferably, the standard method is elemental analysis.
Compared with the prior art, the invention has the following advantages:
the method has the advantages that the substitution degree of hydroxypropyl chitosan is detected simply, conveniently and quickly;
the steps of precisely weighing and dissolving the sample are not needed
The method is also suitable for detection of the handheld infrared absorption spectrometer
The quality control method is suitable for quality control, application type research and development of hydroxypropyl chitosan products and sample detection of a quality inspection mechanism by manufacturers.
Drawings
FIG. 1 is a graph of the infrared absorption spectra (expressed as light transmittance) of chitosan and hydroxypropyl chitosan of varying degrees of substitution. No. 0 is a chitosan sample, and No. 1-6 are hydroxypropyl chitosan samples with gradually increasing substitution degrees.
FIG. 2 is an infrared absorption spectrum (expressed as absorbance) of hydroxypropyl chitosan.
FIG. 3 shows that the hydroxypropyl chitosan in FIG. 2 is at 1700-1200cm-1Enlargement of the range. Wherein A1 is the characteristic peak of methyl group with the whole waveform of 1530-1215cm-1The line connecting the troughs of the light is the absorbance value of the peak height measured by the base line BL 1; a2 is the absorbance value of the peak height of the characteristic peak of the amino group at the C2 position measured by taking the valley line as a base line BL 2.
FIG. 4 is a linear regression standard curve of hydroxypropyl chitosan substitution, where X is A1/A2 and Y is the substitution of the corresponding hydroxypropyl chitosan sample measured using elemental analysis as a standard method.
Detailed Description
The present invention is described in further detail with reference to the following examples, but the embodiments of the present invention are not limited to the examples, and all changes or equivalent substitutions that do not depart from the spirit of the present invention are intended to be included within the scope of the present invention.
Example 1
Reagent: KBr is optical purity, acetanilide is a standard substance, and the KBr is from the national reagent company Limited. Chitosan, derived from lesui bioengineering ltd; hydroxypropyl chitosan, namely hydroxypropyl chitosan No. 0 is taken as a raw material, reacts with propylene oxide at 45-60 ℃ for different time under the alkaline condition, and is purified by a dealkalization method to obtain hydroxypropyl chitosan No. 1-6 with different substitution degrees.
The instrument comprises the following steps: the invention is suitable for various Fourier transform infrared spectrometers, and the instrument used by the invention is a Fourier transform infrared spectrometer TENSOR 27 of Bruker company in Germany; the element analysis method adopted in the standard method for measuring the deacetylation degree of chitosan and the substitution degree of hydroxypropyl chitosan is completed in a testing center (national open laboratory) of a institute of bioenergy of Chinese academy of sciences qualified by the national bureau of measurement, and the used instrument is a Vario EL cube element analyzer of Elementar company of Germany.
Drying a chitosan and hydroxypropyl chitosan sample to remove water;
chitosan and hydroxypropyl chitosan are very hygroscopic and therefore, prior to testing of the sample, they should be thoroughly dried to remove water. The specific drying method comprises the steps of putting a proper amount of hydroxypropyl chitosan sample into a centrifuge tube, drying the hydroxypropyl chitosan sample in an oven at 80 ℃ for 5 hours, then quickly heating the hydroxypropyl chitosan sample to 105 ℃, drying the hydroxypropyl chitosan sample at 105 ℃ for 1.5 hours, quickly closing the cover of the centrifuge tube after the drying is finished, and putting the centrifuge tube into a dryer filled with calcium oxide for later use.
Establishment of detection model
a. Obtaining infrared absorption spectrograms of hydroxypropyl chitosan samples and chitosan samples (hereinafter, both the samples are referred to as samples) with different degrees of substitution by using an infrared absorption spectrometer;
first, the empty tablets are compressed. An appropriate amount of KBr was taken in a mortar and ground until no visible small particles were present to ensure the uniformity and transparency of the compressed tablets. After grinding, filling KBr powder into a sample groove, flattening, filling other parts, then putting into the center of a tablet press, rotating a screw to fix a die, pressing a hand lever up and down to ensure that the pressure is between 12 and 25MPa, and controlling the time to be between 0.5 and 1 min. And demolding the pressed KBr sheet, and putting the KBr sheet into a detector of an infrared absorption spectrometer by using forceps for background detection. The detection conditions are as follows: scanning range 4000--1Scanning 16 times with resolution of 4cm-1；
Next, the sample pieces were pressed. Appropriate amount of KBr and sample were taken in mortar, tabletted and tested in the same procedure as above. Wherein, the samples are respectively chitosan sample No. 0 and hydroxypropyl chitosan sample No. 1-6 with gradually increasing substitution degree. The adding amount of the sample is 1-2mg generally, and most absorption peaks in an obtained infrared absorption spectrogram are required to be in a light transmittance range of 30% -100%;
and finally, performing background deduction on the obtained infrared absorption spectrum to obtain an infrared absorption spectrogram of the required sample.
b. The infrared absorption spectrum of the sample obtained from step a was processed using the application software OPUS of an infrared absorption spectrometer, as shown in fig. 1. The transmittance mode was converted into the absorbance mode, and an infrared absorption spectrum expressed by absorbance was obtained as shown in fig. 2. Taking FIG. 2 as 1700-1200cm-1The area is enlarged, and then figure 3 is obtained. In FIG. 3, 1530 and 1215cm are shown by the whole waveform-1For baseline BL1, the characteristic peak 1460-1456cm was determined by R-baseline integration-1The absorbance value a1 of the peak height of (a); the characteristic peak 1602-1596cm of the amino group at the C2 position was measured-1The absorbance value A2 of the peak height of the base line BL2 is taken as the connecting line of the wave troughs, and the ratio of A1 to A2 is X.
c. Measuring the substitution degree Y of the hydroxypropyl chitosan sample by using an elemental analysis method as a standard method;
first, a standard curve is prepared: establishing a mass gradient standard curve by taking acetanilide as a standard substance; then, 2-4mg of samples (No. 0-6) are respectively weighed and placed in a tin boat, the tin boat is folded and sealed after accurate weighing, the tin boat is placed in a sample cell for determination, each sample is made into three parallel samples, and finally the average value is obtained. Firstly, the deacetylation degree of the chitosan sample is obtained through calculation, and then the substitution degree Y of the hydroxypropyl chitosan sample can be obtained through calculation on the basis.
d. A regression model with good linearity, i.e., Y ═ kX + b, was established for the substitution degree Y of the hydroxypropyl chitosan sample obtained in step c using the ratio X obtained in step b, so as to obtain a model in which k ═ 0.7705 and b ═ 0.8504, i.e., Y ═ 0.7705X-0.8504, as shown in fig. 4 and table 1.
TABLE 1 Fourier transform Infrared Spectroscopy (FTIR) Linear regression model
The third step of detection: the method comprises the steps of drying a hydroxypropyl chitosan sample to be detected according to the method, obtaining an infrared absorption spectrogram through the step a in the step two, obtaining a ratio X according to the step b in the step two, substituting a linear regression model Y obtained in the step d in the step two into 0.7705X-0.8504, and obtaining the substitution degree of the hydroxypropyl chitosan sample to be detected through calculation.
Example 2
The hydroxypropyl chitosan sample A, B, C, D, E, F to be detected is prepared by hydroxypropylation and dealkalization purification. The deacetylation degree of the chitosan raw material is respectively 92.2%, 93.8%, 94.4%, 95.1%, 96.3% and 97.6%. Compared with the raw material chitosan (95.1%) of hydroxypropyl chitosan sample used for establishing the linear regression equation, the deacetylation degree of the hydroxypropyl chitosan sample is different by 3.05% at most. The hydroxypropyl chitosan to be tested which is dried according to the method is subjected to Fourier transform infrared spectroscopy according to the step of the step a and through background detection and background deduction treatment, and therefore an infrared absorption spectrogram is obtained. According to the method of the second step, in the OPUS software, the R-baseline integration method is selected to obtain the whole waveform 1530-1215cm-1As a baseline BL1, 1460-1456cm of characteristic methyl peak was measured-1Absorbance value a1 of the peak intensity of (a); selecting K baseline integral to measure an amino characteristic peak 1602-1596cm at the C2 position-1An absorbance value A2 of peak intensity with two wave troughs as base lines BL 2; thus, the ratio X of a1 to a2 is obtained, and the substitution degree Y of the hydroxypropyl chitosan sample to be detected can be calculated by substituting X into the linear regression equation Y of 0.7705X-0.8504, as shown in table 2.
TABLE 2 substitution of hydroxypropyl chitosan samples to be tested
Example 3
Purification method of hydroxypropyl chitosan by dealkalization method
The raw material chitosan is subjected to hydroxypropylation reaction with propylene oxide under alkaline condition, and then needs to be purified by dealkalization method. The dealkalization purification method of the sample comprises an alcohol ketone-washing precipitation dialysis dealkalization method and a partial neutralization ultrafiltration dealkalization method.
In the alcohol ketone-washing precipitation dialysis alkali-removing method, firstly, the product mixed liquor is filtered by suction to remove the solvent and residual alkali. Dissolving the filtered crude product in water, filtering, adding ethanol into the filtrate to make the filtrate contain 75% of ethanol, adding acetone while stirring to precipitate the swollen chitosan, filtering, adding the precipitate into 75% of ethanol, repeating the steps until the ethanol aqueous solution of hydroxypropyl chitosan is neutral, precipitating with acetone, dissolving the precipitate in water, and freeze-drying to obtain a hydroxypropyl chitosan sample.
In the partially neutralized dialysis dealkalization process, the product mixture is first suction filtered to remove the solvent and residual base. Dissolving the filtered crude product in water, filtering, adding hydrochloric acid into the filtrate to partially neutralize the filtrate to a pH value above 10, then removing alkali by ultrafiltration and NaCl, concentrating the filtrate under reduced pressure, and freeze drying or spray drying to obtain the hydroxypropyl chitosan sample.
Example 4
Dealkalization purification method for hydroxypropyl chitosan sample containing residual acid
In the case of hydroxypropyl chitosan containing residual acid obtained without purification by the method of example 3, an alkali solution may be added, and an excessive amount of alkali solution may be added since the end point of neutralization is difficult to judge, followed by dealkalization according to the method of example 3.
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 and are intended to be equivalent substitutions are included in the scope of the present invention.
Claims (1)
1. A method for measuring the substitution degree of hydroxypropyl chitosan comprises the following steps:
drying hydroxypropyl chitosan samples to remove water, wherein each hydroxypropyl chitosan sample is prepared by hydroxypropylation reaction and dealkalization purification, and is derived from chitosan with known deacetylation degree or chitosan with deacetylation degree not more than 3% different from that of the raw material chitosan;
the method for drying the hydroxypropyl chitosan sample comprises the following steps: drying at 80 deg.C for 4-5 hr, rapidly heating to 105 deg.C, drying for 1.5-2 hr, and taking out the sample from a dryer filled with calcium oxide;
the purification steps by the dealkalization method are as follows: firstly, carrying out suction filtration on a product mixed solution to remove a solvent and residual alkali, adding water to a crude product after suction filtration for dissolving, filtering, adding hydrochloric acid into a filtrate to neutralize the filtrate to a pH value of 10, then carrying out ultrafiltration dealkalization, simultaneously removing NaCl, carrying out reduced pressure concentration on the filtrate, and carrying out freeze drying or spray drying to obtain a hydroxypropyl chitosan sample;
establishment of detection model
a. Obtaining infrared absorption spectrograms of hydroxypropyl chitosan samples with different degrees of substitution by using an infrared absorption spectrometer;
the specific operation of obtaining the infrared absorption spectrogram of hydroxypropyl chitosan samples with different degrees of substitution by using an infrared absorption spectrometer is as follows: pressing a sample tablet, putting a proper amount of KBr and a sample into a mortar, tabletting and detecting in the same steps as the pressing of an empty tablet, wherein the sample is respectively a chitosan sample No. 0, hydroxypropyl chitosan samples No. 1-6 with sequentially increasing degrees of substitution, the adding amount of the sample is 1-2mg, and most absorption peaks in an obtained infrared absorption spectrogram are required to be in a light transmittance range of 30% -100%;
before obtaining the infrared absorption spectrograms of hydroxypropyl chitosan samples with different degrees of substitution by using an infrared absorption spectrometer, background detection is required, and background deduction treatment is carried out;
the specific operation of the background detection is as follows: firstly, pressing an empty tablet, taking a proper amount of KBr in a mortar, grinding the KBr until no visible small particles exist any more so as to ensure the uniformity and transparency of the tablet, after grinding is finished, loading KBr powder into a sample tank, flattening, loading other components, then placing the sample tank into the center of a tablet press, rotating a screw to fix a die, pressing a hand lever up and down to enable the pressure to be between 12 and 25MPa, controlling the time to be between 0.5 and 1min, demolding the pressed KBr tablet, and placing the KBr tablet into a detector of an infrared absorption spectrometer by using tweezers for background detection;
the infrared absorption spectrometer is a Fourier transform infrared spectrometer;
the detection conditions of the infrared absorption spectrometer are as follows: scanning range 4000--1Scanning 16-32 times with resolution of 4cm-1；
b. Measuring 1460-1456cm characteristic methyl peak from the infrared absorption spectrogram of hydroxypropyl chitosan obtained in step a by using application software of an infrared absorption spectrometer-1With the whole waveform 1530-1215cm-1The absorbance value A1 of the peak height of which the connecting line of the wave trough is a base line and the characteristic peak 1602-1596cm of amino group at the C2 position-1The ratio X of the absorbance value A2 of the peak height taking the trough connecting line as the base line;
c. measuring the substitution degree Y of the hydroxypropyl chitosan sample in the step a by a standard method;
the standard method is an elemental analysis method,
the element analysis method comprises the following steps: first, a standard curve is prepared: establishing a mass gradient standard curve by taking acetanilide as a standard substance; then, respectively weighing 2-4mg samples No. 0-6, placing the samples into a tin boat, folding and sealing the tin boat after accurate weighing, placing the tin boat into a sample pool for determination, making three parallel samples for each sample, taking an average value of the results, calculating to obtain the deacetylation degree of the chitosan sample, and then calculating to obtain the substitution degree Y of the hydroxypropyl chitosan sample on the basis;
d. establishing a regression model with good linearity by using the ratio X obtained in the step b to the substitution degree Y of the hydroxypropyl chitosan sample obtained in the step c, namely Y is kX + b, so as to obtain specific values of k and b in the model;
the third step of detection: the method comprises the following steps of obtaining an infrared absorption spectrogram of the hydroxypropyl chitosan sample to be detected in the step a in the step two, obtaining a ratio X in the step b in the step two, substituting the linear regression model in the step d in the step two, and obtaining the substitution degree Y of the hydroxypropyl chitosan sample to be detected through calculation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510575806.8A CN105158193B (en) | 2015-09-11 | 2015-09-11 | Method for measuring substitution degree of hydroxypropyl chitosan |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510575806.8A CN105158193B (en) | 2015-09-11 | 2015-09-11 | Method for measuring substitution degree of hydroxypropyl chitosan |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105158193A CN105158193A (en) | 2015-12-16 |
| CN105158193B true CN105158193B (en) | 2021-07-13 |
Family
ID=54799128
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510575806.8A Active CN105158193B (en) | 2015-09-11 | 2015-09-11 | Method for measuring substitution degree of hydroxypropyl chitosan |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105158193B (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3947391B2 (en) * | 2001-11-28 | 2007-07-18 | 独立行政法人 日本原子力研究開発機構 | Method for producing chitin derivative and / or chitosan derivative having bridge structure |
| CN104697944B (en) * | 2014-12-30 | 2017-08-08 | 青岛科技大学 | The assay method of hydroxypropyl chitosan substitution value |
-
2015
- 2015-09-11 CN CN201510575806.8A patent/CN105158193B/en active Active
Non-Patent Citations (3)
| Title |
|---|
| HPCTS的制备与性能及其在织物整理上的应用研究;季莉;《中国优秀博硕士学位论文全文数据库（硕士）工程科技Ⅰ辑》;20051215(第8期);第16页"2.3.1 HPCTS的合成"、第25页"2.4.3.2 红外光谱分析" * |
| 分离纯化方法对羟丙基壳聚糖结构及取代度测定的影响;，张永勤 等;《青岛科技大学学报(自然科学版)》;20150630;第36卷(第3期);第252页"1.2.1 醇洗酮沉法制备羟丙基壳聚糖" * |
| 邻苯二甲酰化壳聚糖中酰胺酸取代度的红外测定;董炎明 等;《化学通报》;20020228(第2期);第124-125页，图2-图3 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN105158193A (en) | 2015-12-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105115927B (en) | Method for measuring substitution degree of hydroxypropyl chitosan | |
| de Alvarenga et al. | An approach to understanding the deacetylation degree of chitosan | |
| Noda | Frontiers of two-dimensional correlation spectroscopy. Part 1. New concepts and noteworthy developments | |
| Zhang et al. | Determination of the degree of deacetylation of chitosan by potentiometric titration preceded by enzymatic pretreatment | |
| CN112326565B (en) | Method for correcting turbidity influence during detection of COD (chemical oxygen demand) of water quality by ultraviolet-visible spectrometry | |
| CN101444604B (en) | Chinese medicine granule to treat children anorexia and preparation method thereof and detection method | |
| CN105136710B (en) | Method for measuring substitution degree of hydroxypropyl chitosan | |
| CN106596454B (en) | A kind of starch Fourier transform decaying In situ ATR-FTIR sample preparation apparatus and application method | |
| CN110068632B (en) | Method for measuring amino content of chitosan derivative based on headspace gas chromatography | |
| CN105158193B (en) | Method for measuring substitution degree of hydroxypropyl chitosan | |
| CN105203493B (en) | Method for measuring substitution degree of hydroxypropyl chitosan | |
| CN105277507B (en) | Method for measuring substitution degree of hydroxypropyl chitosan | |
| CN105300916B (en) | Method for measuring substitution degree of hydroxypropyl chitosan | |
| CN113092553B (en) | Method for detecting glucose by enzyme-free glucose sensor | |
| Zhou et al. | A molecularly imprinted fiber array solid-phase microextraction strategy for simultaneous detection of multiple estrogens | |
| CN110006979B (en) | Diluteoside D electrochemical sensor based on nano CuO/Nafion membrane modified electrode | |
| CN109541002B (en) | Method for determining bound acid in cellulose acetate hydrolysis process | |
| CN110987716B (en) | Method for measuring concentration of boric acid in iodine polarizing film processing tank liquid | |
| CN107957403B (en) | Method for measuring chitosan content by using carmine as probe through ultraviolet spectrophotometry | |
| CN111879717A (en) | Method for rapidly evaluating internal components and quality of traditional Chinese medicine formula granules | |
| Firdaus et al. | Colorimetric Sensing of Ascorbic Acid Using Cu-Phen MOFs and Subsequent Digital Image Analysis with Smartphone | |
| Firdaus et al. | Science and Technology Indonesia | |
| CN116162277B (en) | Method for rapidly measuring phosphate radical in water | |
| Tian et al. | Preparation and characterization of n-octyl pyridine tetrafluoroborate | |
| CN107036989B (en) | A method of measurement chrome tanning agent active constituent content |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |