AU2021105314A4 - An amino nanocellulose and preparation method thereof - Google Patents
An amino nanocellulose and preparation method thereof Download PDFInfo
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- AU2021105314A4 AU2021105314A4 AU2021105314A AU2021105314A AU2021105314A4 AU 2021105314 A4 AU2021105314 A4 AU 2021105314A4 AU 2021105314 A AU2021105314 A AU 2021105314A AU 2021105314 A AU2021105314 A AU 2021105314A AU 2021105314 A4 AU2021105314 A4 AU 2021105314A4
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- AU
- Australia
- Prior art keywords
- nanocellulose
- amino
- solution
- amount
- lysine
- Prior art date
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- 229920001046 Nanocellulose Polymers 0.000 title claims abstract description 68
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 title claims abstract description 37
- 238000002360 preparation method Methods 0.000 title claims abstract description 20
- VHYFNPMBLIVWCW-UHFFFAOYSA-N 4-Dimethylaminopyridine Chemical compound CN(C)C1=CC=NC=C1 VHYFNPMBLIVWCW-UHFFFAOYSA-N 0.000 claims abstract description 36
- LMDZBCPBFSXMTL-UHFFFAOYSA-N 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide Chemical compound CCN=C=NCCCN(C)C LMDZBCPBFSXMTL-UHFFFAOYSA-N 0.000 claims abstract description 33
- 239000004472 Lysine Substances 0.000 claims abstract description 22
- KDXKERNSBIXSRK-UHFFFAOYSA-N Lysine Natural products NCCCCC(N)C(O)=O KDXKERNSBIXSRK-UHFFFAOYSA-N 0.000 claims abstract description 22
- 239000000243 solution Substances 0.000 claims description 31
- 238000006243 chemical reaction Methods 0.000 claims description 23
- 239000000126 substance Substances 0.000 claims description 16
- 239000007853 buffer solution Substances 0.000 claims description 15
- 229920002678 cellulose Polymers 0.000 claims description 13
- 239000001913 cellulose Substances 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 12
- 239000003153 chemical reaction reagent Substances 0.000 claims description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- KDXKERNSBIXSRK-YFKPBYRVSA-N L-lysine Chemical compound NCCCC[C@H](N)C(O)=O KDXKERNSBIXSRK-YFKPBYRVSA-N 0.000 claims description 6
- 238000003756 stirring Methods 0.000 claims description 6
- 125000002791 glucosyl group Chemical group C1([C@H](O)[C@@H](O)[C@H](O)[C@H](O1)CO)* 0.000 claims description 4
- 239000000376 reactant Substances 0.000 claims description 4
- 229920002749 Bacterial cellulose Polymers 0.000 claims description 3
- 239000005016 bacterial cellulose Substances 0.000 claims description 3
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 claims description 3
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims description 3
- 239000002159 nanocrystal Substances 0.000 claims description 3
- SXGZJKUKBWWHRA-UHFFFAOYSA-N 2-(N-morpholiniumyl)ethanesulfonate Chemical compound [O-]S(=O)(=O)CC[NH+]1CCOCC1 SXGZJKUKBWWHRA-UHFFFAOYSA-N 0.000 claims description 2
- 238000004220 aggregation Methods 0.000 claims description 2
- 230000002776 aggregation Effects 0.000 claims description 2
- 238000004140 cleaning Methods 0.000 claims description 2
- 239000003431 cross linking reagent Substances 0.000 claims description 2
- 230000003247 decreasing effect Effects 0.000 claims description 2
- 238000007865 diluting Methods 0.000 claims description 2
- 239000011259 mixed solution Substances 0.000 claims description 2
- 239000007787 solid Substances 0.000 claims description 2
- 239000002904 solvent Substances 0.000 claims description 2
- 239000003814 drug Substances 0.000 abstract description 5
- 238000005576 amination reaction Methods 0.000 abstract 1
- 239000003054 catalyst Substances 0.000 abstract 1
- 239000007987 MES buffer Substances 0.000 description 8
- 239000000047 product Substances 0.000 description 4
- 239000008055 phosphate buffer solution Substances 0.000 description 3
- 229910019142 PO4 Inorganic materials 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 2
- 239000010452 phosphate Substances 0.000 description 2
- QIVUCLWGARAQIO-OLIXTKCUSA-N (3s)-n-[(3s,5s,6r)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl]-2-oxospiro[1h-pyrrolo[2,3-b]pyridine-3,6'-5,7-dihydrocyclopenta[b]pyridine]-3'-carboxamide Chemical compound C1([C@H]2[C@H](N(C(=O)[C@@H](NC(=O)C=3C=C4C[C@]5(CC4=NC=3)C3=CC=CN=C3NC5=O)C2)CC(F)(F)F)C)=C(F)C=CC(F)=C1F QIVUCLWGARAQIO-OLIXTKCUSA-N 0.000 description 1
- -1 AMINO Chemical class 0.000 description 1
- 230000000844 anti-bacterial effect Effects 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 231100000135 cytotoxicity Toxicity 0.000 description 1
- 230000003013 cytotoxicity Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000003607 modifier Substances 0.000 description 1
- 229930014626 natural product Natural products 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 239000006174 pH buffer Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
- C08B15/00—Preparation of other cellulose derivatives or modified cellulose, e.g. complexes
- C08B15/05—Derivatives containing elements other than carbon, hydrogen, oxygen, halogens or sulfur
- C08B15/06—Derivatives containing elements other than carbon, hydrogen, oxygen, halogens or sulfur containing nitrogen, e.g. carbamates
Abstract
The present invention provides amino nanocellulose and a preparation
method thereof and belongs to the technical field of preparation of amino
nanocellulose.In the present invention, by
utilizing1-ethyl-(3-dimethylaminopropyl) carbodiimide (EDC) and
4-dimethylaminopyridine (DMAP) as catalysts, lysine is grafted onto the
surface of nanocellulose, thereby realizing amination of the nanocellulose. In
the prepared amino nanocellulose, the lysine is directly linked to the
nanocellulose, which is conducive to increasing the biocompatibility of the
amino nanocellulose and widening an application range of the amino
nanocellulose in the field of biological medicine.
11
Description
The present invention relates to amino nanocellulose and a preparation
method thereof, particularly to a method for preparing the amino
nanocelluloseat normal temperatures and pressures, and belongs to the technical
field of preparation of the amino nanocellulose.
Cellulose is a natural compound having the largest reserve, and is a
renewable resource. Amino nanocellulose prepared by cellulose modification
has antibacterial property and excellent biocompatibility (e.g., lysine-modified
nanocellulose may decrease cytotoxicity of a nanometer material), and shows
excellent application prospects in the field of biological medicine. However, a
preparation process of the amino nanocellulose is complicated at present; and
some compounds toxic to organisms may be introduced in partial reaction
processes, thereby greatly increasing environmental treatment cost and limiting
applications of the amino nanocellulose in the field of biological medicine.
With respect to the above problem, the present invention provides amino
nanocellulose and a preparation method thereof. In the present invention, by
taking lysine as a modifier, carboxyl in the lysine is linked to hydroxyl in
nanocellulose in a pH buffer solution by utilizing EDC and DMAP as
cross-linking agents, to produce the amino nanocellulose.Thepreparation process in the present invention is green and environment-friendly, and contributes to maintaining excellent biocompatibility of the cellulose and widening an application range of the amino nanocellulose in the field of biological medicine. Technical solutions of the present invention are as follows:
According to the method for preparing the amino nanocellulose, lysineis
cross-linked onto the surface of nanocellulose at normal temperatures and
pressures, thereby preparing the amino nanocellulose. The method includes the
following specific steps:
(1) preparing a pH buffer solution having a concentration of 0.01-1 M,
wherein the buffer solution is preferably a morpholineethanesulfonic acid (MES)
buffer solution;
(2) diluting the nanocellulosewith the pH buffer solution until solid content
is not more than 4% (a ratio of mass of the nanocellulose to a volume of water,
g/mL); then homogenizing the nanocellulose by a homogenizer; and uniformly
dispersing the nanocellulose for later use, wherein a pH value of the solution is
5.5-7.0;
(3) adding the homogenized nanocellulose into a reaction container; then
respectively adding lysine, 1-ethyl-(3-dimethylaminopropyl) carbodiimide
(EDC) and 4-dimethylaminopyridine (DMAP) to obtain a solution A, wherein
the final concentrations of the three reagents are respectively as follows:an
amount-of-substance of the lysine is 1-3 times that of the amount-of-substance
of glucose units in the nanocellulose; the amount-of-substance concentration of the EDC is 0.01-1 M; the amount-of-substance concentration of the DMAP is
0.01-0.4 M; and the pH value of the solution is 5.5-7.0 in the reaction process;
(4) or changing a reactant adding sequence in the step (2) as follows:
preparing a mixed solution of the lysine, EDC and DMAP with a pH buffer
solution; carrying out a reaction while stirring for 5-60 minutes; then adding the
homogenized nanocelluloseobtained in the step (2) to obtain a solution B,
wherein final concentrations of the three reagents are respectively as follows:an
amount-of-substance of the lysine is 1-3 times that of the amount-of-substance
of glucose units in the nanocellulose; the amount-of-substance concentration of
the EDC is 0.01-lM; the amount-of-substance concentration of the DMAP is
0.01-0.4 M; and the pH value of the solution is 5.5-7.0 in the reaction process;
(5) reacting the solution A obtained in the step (3) or the solution B
obtained in the step (4) at normal temperatures and pressures for 2-28 hours,
wherein aggregation betweenthe nanocelluloseisdecreased by virtue of stirring
and other methods in the reaction processto enhance the mass transfer
efficiency of the reactants; and
(6) cleaning the cellulose with pure water after the reaction is over, so that
the final conductivity is not more than 10 tS/cm.
Preferably, in the step (1), a solvent of the buffer solution in the step (1) is
the pure water.
Preferably, in the step (2), the nanocellulose is selected from any one of
cellulose nanofibril, cellulose nanocrystals or bacterial cellulose.
The present invention further includes amino nanocellulose obtained by
the above preparation method.
Compared with the prior art, the present invention has advantages as
follows:
(1) In the present invention, the reaction is carried out in the normal
temperature and pressure environment; reaction conditions are mild; the use of
an organic solvent is avoided; the environmental treatment process is avoided;
the preparation cost of the amino nanocellulose is decreased; and a green
method for preparing the amino nanocellulose is provided.
(2) By virtue of catalysis of the EDC and the DMAP, the carboxyl in the
lysine is directly bound to the hydroxyl in the nanocellulose, thereby
simplifying the preparation process procedures of the amino nanocellulose.
(3) The lysine in the reaction product is directly linked to the nanocellulose,
which is conducive to increasing the biocompatibility of the amino
nanocellulose and widening the application range of the amino nanocellulose in
the field of biological medicine.
FIG.1 is a flow chart of a reaction process of binding lysine on the surface
of nanocellulose to produce amino nanocellulose in the present invention.
The present invention will be further described below in combination with
specific embodiments. Advantages and characteristics of the present invention
will be clearer along the descriptions. However, the embodiments are merely exemplary, rather than constituting any limitation to the scope of the present invention. It should be understood that, details and forms of technical solutions of the present invention may be modified or replaced by those skilled in the art without departing from the spirit and scope of the present invention. However, these modifications and replacements shall fall within the protection scope of the present invention.
Examplel:An amino nanocellulose and a preparation method thereof
Steps wereas follows:
(1) An MES buffer solution with a concentration of 0.1 M was prepared,
wherein a pH value was equal to 6.0;
(2) lysine, EDC and DMAP were respectively added into the MES buffer
solution, and final concentrations of the three reagents were respectively 0.6
mM, 0.2M and 0.2M;after dissolved, the three reagents were reacted while
stirring for 10 minutes;
(3) cellulose nanofibril was added into the MES buffer solution to prepare
a 0.2% solution; the solution was homogenized and dispersed uniformly and
then added into the step (2); the solution was continuously stirred; and a
reaction was carried out at normal temperatures and pressures for 24 hours; and
(4) when the reaction was over, the product was cleaned with pure water
until the conductivity was not more than 10 tS/cm.
Example2:An amino nanocellulose and a preparation method thereof
Steps wereas follows:
(1) A phosphate buffer solution with a concentration of 0.2 M was
prepared, wherein a pH value was equal to 6.5;
(2) lysine, EDC and DMAP were respectively added into the phosphate
buffer solution, and final concentrations of the three reagents were respectively
0.2mM, 0.8M and 0.2M; after dissolved, the three reagents were reacted while
stirring for 30 minutes;
(3) bacterial cellulose was added into the MES buffer solution (0.2 M, pH
of 6.5) to prepare a 0.8% (g/mL) solution; the solution was homogenized and
dispersed uniformly and then added into the step (2); the solution was
continuously stirred; and a reaction was carried out at normal temperatures and
pressures for 26 hours; and
(4) when the reaction was over, the product was cleaned with pure water
until the conductivity was not more than 10 tS/cm.
Example 3:An amino nanocellulose and a preparation method thereof
Steps wereas follows:
(1) An MES buffer solution with a concentration of 0.1 M was prepared,
wherein a pH value was equal to 6.0;
(2) cellulose nanocrystals were added into the MES buffer solution to
prepare a 0.2% solution; the solution was homogenized and dispersed
uniformly to obtain nanocellulose for later use;
(3) lysine, EDC and DMAP were respectively added into the MES buffer
solution, and final concentrations of the three reagents were respectively
0.6mM, 0.2M and 0.2M; the homogenized nanocellulose in the step (2) was
added and stirred; and a reaction was carried out at normal temperatures and
pressures for 16 hours;
(4) when the reaction was over, the product was cleaned with pure water
until the conductivity was not more than 10 tS/cm.
Example4:An amino nanocellulose and a preparation method thereof
Steps were as follows:
(1) A phosphate buffer solution having a concentration of 0.2 M was
prepared, wherein a pH value was equal to 6.8;
(2) cellulose nanofibril was added into the phosphate buffer solution to
prepare a 0.5% solution; and the solution was homogenized and dispersed
uniformly for later use;
(3) lysine, EDC and DMAP were respectively added into the phosphate
buffer solution, and final concentrations of the three reagents were respectively
0.2mM, 0.2Mand 0.2M; the homogenized nanocellulose in the step (2) was
added and stirred; and a reaction was carried out at normal temperatures and
pressures for 4 hours; and
(4) when the reaction was over, the product was cleaned with pure water
until the conductivity was not more than 10 tS/cm.
Test example
A flow chart of a reaction process of binding lysine on the surface of
nanocellulose to produce amino nanocellulosewasshown as FIG. 1. Due to the binding of lysine on the surface of nanocellulose, the surface of nanocelluloseoriginally having negative chargeshadpositive charges. Zeta potential detection of the amino nanocellulose prepared in the present invention wasshown inTable 1.
Table 1
Sample name Zeta potential (eV)
Cellulose nanofibril -40.5 1.9
Amino nanocellulose obtained in Examplel 37.3 2.3
Amino nanocellulose obtained in Example2 32.3 2.3
Amino nanocellulose obtained in Example3 31.8 1.7
Amino nanocellulose obtained in Example 4 26.5 2.6
Claims (6)
1. A method for preparing amino nanocellulose, wherein carboxyl in lysine
is linked to hydroxyl in nanocellulose in a pH buffer solution by utilizing EDC
and DMAP as cross-linking agents, to produce amino nanocellulose.
2. The preparation method according to claim 1, comprising the following
steps:
(1) preparing a pH buffer solution having a concentration of 0.01-1 M;
(2)diluting the nanocellulose with the pH buffer solution until solid content
is not more than 4% (a ratio of mass of the nanocellulose to a volume of water,
g/mL); then homogenizing the nanocellulose by a homogenizer; and uniformly
dispersing the nanocellulose for later use;
(3) adding the homogenized nanocellulose into a reaction container; then
respectively adding lysine, 1-ethyl-(3-dimethylaminopropyl) carbodiimide
(EDC) and 4-dimethylaminopyridine (DMAP) to obtain a solution A, wherein
the final concentrations of the three reagents are respectively as follows: an
amount-of-substance of the lysine is 1-3 times that of the amount-of-substance
of glucose units in the nanocellulose; the amount-of-substance concentration of
the EDC is 0.01-1 M; the amount-of-substance concentration of the DMIAP is
0.01-0.4 M;
(4) or changing a reactant adding sequence in the step (3) as follows:
preparing a mixed solution of the lysine, EDC and DMAP with a pH buffer
solution; carrying out a reaction while stirring for 5-60 minutes; then adding the homogenized nanocellulose obtained in the step (2) to obtain a solution B, wherein final concentrations of the three reagents are respectively as follows: an amount-of-substance of the lysine is 1-3 times that of the amount-of-substance of glucose units in the nanocellulose; the amount-of-substance concentration of the EDC is 0.01-lM; the amount-of-substance concentration of the DMAP is 0.01-0.4 M;
(5) reacting the solution A obtained in the step (3) or the solution B
obtained in the step (4) at normal temperatures and pressures for 2-28 hours,
wherein aggregation between the nanocelluloses decreased by virtue of stirring
and other methods in the reaction process to enhance the mass transfer
efficiency of the reactants; and
(6) cleaning the cellulose with pure water after the reaction is over, so that
the final conductivity is not more than 10 tS/cm.
3. The preparation method according to claim 2, wherein in the step (1), the
pH buffer solution is morpholineethanesulfonic acid buffer.
4. The preparation method according to claim 2, wherein in the step (1), a
solvent of the buffer solution in the step (1) is the pure water.
5. The preparation method according to claim 2, wherein in the step (2), the
nanocellulose is selected from any one of cellulose nanofibril, cellulose
nanocrystals or bacterial cellulose.
6. An amino nanocellulose obtained by the preparation method of any one
of claims I to 5.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110899384.5 | 2021-08-06 | ||
| CN202110899384.5A CN113603797B (en) | 2021-08-06 | 2021-08-06 | Amino nano-cellulose and preparation method thereof |
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| AU2021105314A4 true AU2021105314A4 (en) | 2021-10-07 |
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| CN (1) | CN113603797B (en) |
| AU (1) | AU2021105314A4 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114656574B (en) * | 2022-04-26 | 2023-10-24 | 陕西科技大学 | Preparation method of cellulose-indolyl antibacterial material |
| CN114933724B (en) * | 2022-06-21 | 2023-09-22 | 陕西科技大学 | Preparation method of nonionic cellulose/polycaprolactone-based antibacterial film |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103343001A (en) * | 2013-07-10 | 2013-10-09 | 福建农林大学 | Method for preparing pH fluorescent response nano cellulose |
| CN103405778B (en) * | 2013-07-15 | 2015-04-29 | 福建农林大学 | Colon-targeted pro-drug based on nanometer cellulose carrier and preparation method of colon-targeted pro-drug |
| CN105968215B (en) * | 2016-03-31 | 2018-12-28 | 北京理工大学 | A kind of application of the method for nano-cellulose grafted amino group acid in terms of ultrafiltration membrane |
| JP6737453B2 (en) * | 2016-11-22 | 2020-08-12 | 株式会社ダイセル | Cellulose derivative, metal removing material containing the same, and metal removing method using the same |
| CN107446054B (en) * | 2017-08-11 | 2021-05-18 | 武汉理工大学 | Biomass-based nano particle and preparation method and application thereof |
| JP2020019846A (en) * | 2018-07-30 | 2020-02-06 | 株式会社ダイセル | Cellulose derivative, heavy metal removal material containing the same, and heavy metal removing method using the same |
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| CN113603797A (en) | 2021-11-05 |
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