阅读说明：本技术 一种壳聚糖基梳型两亲温敏性聚合物及其制备方法和应用 (Chitosan-based comb type amphiphilic temperature-sensitive polymer and preparation method and application thereof ) 是由 全志龙 周双华 杨柏超 于 2020-06-05 设计创作，主要内容包括：本发明公开了一种具有上临界溶解温度特性的壳聚糖基梳型两亲温敏性聚合物,基于组成及环境温度变化,此壳聚糖基两亲温敏性聚合物在水溶液分散体系中形成粒径在120nm～2000nm范围内可调控的胶束,在30～55℃范围内具有上临界溶解温度的温敏刺激-响应特性,这种具有上临界溶解温度特性的壳聚糖基梳型两亲温敏性聚合物可以作为温敏智能性药物载体应用。本发明还公开了上述壳聚糖基梳型两亲温敏性聚合物的制备方法。(The invention discloses a chitosan-based comb-type amphiphilic temperature-sensitive polymer with an upper critical solution temperature characteristic, based on composition and environmental temperature change, the chitosan-based amphiphilic temperature-sensitive polymer forms micelles with adjustable particle sizes within the range of 120 nm-2000 nm in an aqueous solution dispersion system, and has a temperature-sensitive stimulus-response characteristic of the upper critical solution temperature within the range of 30-55 ℃, and the chitosan-based comb-type amphiphilic temperature-sensitive polymer with the upper critical solution temperature characteristic can be used as a temperature-sensitive intelligent drug carrier. The invention also discloses a preparation method of the chitosan-based comb type amphiphilic temperature-sensitive polymer.)

1. A chitosan-based comb-type amphiphilic temperature-sensitive polymer is prepared by taking chitosan and alkyl polyethylene glycol glycidyl ether compounds as raw materials, and is characterized in that: the polymer chain of the chitosan-based amphiphilic temperature-sensitive polymer contains at least one of the characteristic structures shown in formulas I-IV:

in formula I, m1, m2 and m3 are integers respectively, and m2 is not zero,

the value of [ (m1+ m2)/(m1+ m2+ m3) ] x 100% is not more than the deacetylation degree of the chitosan, n1 is more than or equal to 4, n1 ' is more than or equal to 0 and less than or equal to 20, n2 is more than or equal to 9, n2 ' is more than or equal to 0 and less than or equal to 41, m is more than or equal to 3, and m ' is more than or equal to 0 and less than or equal to 80;

in formula II, m1, m2 and m3 are integers respectively, and m2 is not zero,

[(m1+m2)/(m1+m2+m3)]× 100% is not more than the deacetylation degree of chitosan, n1 is not less than 4, n1 ' is not less than 0 and not more than 20, n2 is not less than 9, n2 ' is not less than 0 and not more than 41, m is not less than 3, m ' is not less than 0 and not more than 80, y is an integer not more than 3, X^-＝Cl^-,Br^-,I^-,Ac^-,HSO₄ ^-,HSO₃ ^-,NO₃ ^-；

In formula III, m1, m2 and m3 are integers respectively, and m2 is not zero,

the value of [ (m1+ m2)/(m1+ m2+ m3) ] x 100% is not more than the deacetylation degree of the chitosan, n1 is more than or equal to 4, n2 is more than or equal to 9, and m is more than or equal to 3;

in formula IV, m1, m2 and m3 are integers respectively, and m2 is not zero,

[(m1+m2)/(m1+m2+m3)]× 100% is not more than the deacetylation degree of chitosan, n1 is not less than 4, n2 is not less than 9, m is not less than 3, y is an integer not more than 3, X^-＝Cl^-,Br^-,I^-,Ac^-,HSO₄ ^-,HSO₃ ^-,NO₃ ^-；

The aqueous solution dispersion system of the chitosan-based comb-type amphiphilic temperature-sensitive polymer has a temperature-sensitive characteristic that the upper critical solution temperature is adjustable within the range of 30-55 ℃, and the particle size of micelles formed by self-assembly of the chitosan-based comb-type amphiphilic temperature-sensitive polymer is adjustable within the range of 120-2000 nm.

2. A method for preparing a chitosan-based comb-type amphiphilic polymer according to claim 1, characterized in that: the method comprises the following steps:

step 1, dissolving chitosan in water or 1 wt% acetic acid water solution to prepare 0.03 wt% -5 wt% chitosan solution;

step 2, adding the chitosan solution obtained in the step 1 and containing- (CH) in the structure under stirring at room temperature₂CH₂O)_m-OC_n1H_n2And/or contains- (CH)₂CH₂O)_m’-OC_n1’H_n2’The alkyl polyethylene glycol glycidyl ether compound is subjected to a grafting reaction to obtain a chitosan-based comb-type amphiphilic temperature-sensitive polymer solution containing a characteristic structure shown as a formula I or a formula III in a polymer chain, and a target product is obtained after filtering, dialysis and freeze drying in sequenceThe alkyl polyethylene glycol glycidyl ether compound and the-NH in the chitosan₂The amount of the substance(s) in (b) is in the ratio R_EP0.001-2: 1;

and 3, protonating the chitosan-based comb type amphiphilic temperature-sensitive polymer solution containing the characteristic structure shown in the formula I or the formula III to obtain a protonated chitosan-based comb type amphiphilic temperature-sensitive polymer solution containing the characteristic structure shown in the formula II or the formula IV, and sequentially filtering, dialyzing, freezing and drying to obtain a protonated target product.

3. The method for preparing a chitosan-based comb-type amphiphilic thermo-sensitive polymer according to claim 2, wherein: in the step 1, the deacetylation degree of the chitosan is more than or equal to 60%, and the viscosity of the chitosan is 5-1000 mPa & s.

4. The method for preparing a chitosan-based comb-type amphiphilic thermo-sensitive polymer according to claim 3, wherein: in the step 1, the deacetylation degree of the chitosan is more than or equal to 90%, and the viscosity of the chitosan is 5-500 mPa & s.

5. The method for preparing a chitosan-based comb-type amphiphilic thermo-sensitive polymer according to claim 2, wherein: in step 2, the added alkyl polyethylene glycol glycidyl ether compound is firstly dissolved in a water/isopropanol mixed solvent to form a mixed solution of the alkyl polyethylene glycol glycidyl ether compound, V_{Water (W)}/V_{Isopropanol (I-propanol)}3/7-7/3, wherein the concentration of the mixed solution of the alkyl polyethylene glycol glycidyl ether compound is 0.005-0.5 mol/L.

6. The method for preparing a chitosan-based comb-type amphiphilic thermo-sensitive polymer according to claim 2, wherein: in step 3, the protonation reagent is at least one of hydrochloric acid, hydrobromic acid, hydroiodic acid, acetic acid, nitric acid, sulfuric acid and sulfurous acid, and protons in the reagent and-NH in the chitosan in step 1₂The amount of the substance(s) ofR_pIs 0.001-1: 1.

7. The use of the chitosan-based comb-type amphiphilic polymer according to claim 1 as a temperature-sensitive smart drug carrier.

Technical Field

The invention relates to the technical field of chitosan-based intelligent materials, in particular to a chitosan-based comb-type amphiphilic temperature-sensitive polymer with an upper critical solution temperature characteristic, and a preparation method and application thereof.

Background

The chitosan is mainly from the shells of shrimps and crabs, has wide sources, is the only abundant basic cationic polysaccharide in the nature and is biological poisonSmall in property, has good histocompatibility, biodegradability, adhesion function and the like, and is deeply researched and widely applied in the fields of medicine and biology. The temperature-sensitive chitosan-based graft polymer keeps the excellent performance of the chitosan matrix and has the temperature stimulation-response capability. Recent studies have found that chitosan-based physical gels with temperature sensitivity can be obtained by adding alkaline salts, hydroxyl-containing polymers or performing derivatization and grafting reactions on chitosan. Chenite and the like use polyhydric alcohol sodium glycerophosphate to neutralize chitosan for reaction to obtain a chitosan-sodium glycerophosphate compound which has neutral pH value and can keep liquid state for a long time at normal temperature, wherein the compound is temperature-sensitive gel, namely, the compound can keep liquid state for a long time at room temperature or below, and the compound is gelatinized into hydrogel after the temperature is raised to physiological body temperature (37 ℃); is considered to be promising as an injectable, parenteral drug carrier, especially as a carrier and cell scaffold material for biomacromolecule preparations (Chenite A, Chaput C, Wang D, Combes C, Buschmann M.D, Hoemann C.D, LerouxJ.C, Atkinson B.L, Binette F, Selmani A. novel injectable neutral solutions of chitosan for biomedical biological molecules in situ [ J.]Biomaterials,2000,21(21): 2155-2161.). Also, for example, Chinese patent with patent application No. 201210220246.0 discloses a temperature sensitive chitosan derivative-hydroxypentyl chitosan and a preparation method thereof, which prepares a chitosan with a low critical solution temperature of 17 ℃ (2% w)_tV) and can be rapidly solidified into a stable gel-state chitosan-based temperature-sensitive material from a liquid state at a physiological temperature of 37 ℃.

The research on temperature-sensitive polymer materials has been focused on systems having a lower critical solution temperature characteristic, but many polymer systems having an upper critical solution temperature characteristic have been reported. A comb-type temperature-sensitive polymer based on chitosan-based comb-type amphiphilic temperature-sensitive polymer, namely chitosan-based-g-alkyl polyethylene glycol and having the characteristic of upper critical solution temperature is not reported.

Disclosure of Invention

The invention aims to provide a chitosan-based comb-type amphiphilic temperature-sensitive polymer with an upper critical solution temperature characteristic, when the temperature is changed within the range of 30-55 ℃, the chitosan-based comb-type amphiphilic temperature-sensitive polymer forms micelles in an aqueous solution by self-assembly under the hydrophilic and hydrophobic effects, the composition and the temperature change influence the particle size of the micelles to be adjustable within the range of 120-2000 nm, and the chitosan-based polymer with the upper critical solution temperature characteristic has the temperature-sensitive stimulus-response characteristic of the upper critical solution temperature, can be used as a temperature-sensitive intelligent drug carrier, and can adjust and control the release rate and the accumulated release amount of drugs along with the temperature change.

The invention also aims to provide a preparation method of the chitosan-based comb-type amphiphilic temperature-sensitive polymer with the upper critical solution temperature characteristic, and the chitosan-based comb-type amphiphilic temperature-sensitive polymer with the upper critical solution temperature characteristic is obtained in a condensation-grafting reaction mode under the normal temperature condition.

In order to achieve the above purpose, the solution of the invention is:

a chitosan-based comb-type amphiphilic temperature-sensitive polymer is prepared by taking chitosan and alkyl polyethylene glycol glycidyl ether compounds as raw materials, wherein a polymer chain of the chitosan-based amphiphilic temperature-sensitive polymer contains at least one of characteristic structures shown in formulas I-IV:

in formula I, m1, m2 and m3 are integers respectively, and m2 is not zero,

the value of [ (m1+ m2)/(m1+ m2+ m3) ] x 100% is not more than the deacetylation degree of the chitosan, n1 is more than or equal to 4, n1 ' is more than or equal to 0 and less than or equal to 20, n2 is more than or equal to 9, n2 ' is more than or equal to 0 and less than or equal to 41, m is more than or equal to 3, and m ' is more than or equal to 0 and less than or equal to 80;

in formula II, m1, m2 and m3 are integers respectively, and m2 is not zero,

[(m1+m2)/(m1+m2+m3)]× 100% is not more than the deacetylation degree of chitosan, n1 is not less than 4, n 1' is not less than 020, n2 is more than or equal to 9, n2 'is more than or equal to 0 and less than or equal to 41, m is more than or equal to 3, m' is more than or equal to 0 and less than or equal to 80, and y is an integer not more than 3; x^-＝Cl^-,Br^-,I^-,Ac^-,HSO₄ ^-,HSO₃ ^-,NO₃ ^-；

In formula III, m1, m2 and m3 are integers respectively, and m2 is not zero,

the value of [ (m1+ m2)/(m1+ m2+ m3) ] x 100% is not more than the deacetylation degree of the chitosan, n1 is more than or equal to 4, n2 is more than or equal to 9, and m is more than or equal to 3;

in formula IV, m1, m2 and m3 are integers respectively, and m2 is not zero,

[(m1+m2)/(m1+m2+m3)]× 100% is not more than the deacetylation degree of chitosan, n1 is not less than 4, n2 is not less than 9, m is not less than 3, y is an integer not more than 3, X^-＝Cl^-,Br^-,I^-,Ac^-,HSO₄ ^-,HSO₃ ^-,NO₃ ^-；

The aqueous solution dispersion system of the chitosan-based comb-type amphiphilic temperature-sensitive polymer has the temperature-sensitive characteristic that the upper critical solution temperature is adjustable within the range of 30-55 ℃, and the particle size of micelles formed by self-assembly of the chitosan-based comb-type amphiphilic temperature-sensitive polymer is adjustable within the range of 120-2000 nm along with the change of temperature.

A preparation method of a chitosan-based comb-type amphiphilic temperature-sensitive polymer comprises the following steps:

step 1, dissolving chitosan in water or 1 wt% acetic acid water solution to prepare 0.03 wt% -5 wt% chitosan solution;

step 2, adding the chitosan solution obtained in the step 1 and containing- (CH) in the structure under stirring at room temperature₂CH₂O)_m-OC_n1H_n2And/or contains- (CH)₂CH₂O)_m’-OC_n1’H_n2’The alkyl polyethylene glycol glycidyl ether compound is subjected to a grafting reaction to obtain a chitosan-based comb-type amphiphilic temperature-sensitive polymer solution containing a characteristic structure shown as a formula I or a formula III in a polymer chain, and a target product is obtained after filtering, dialysis and freeze drying are sequentially carried out, wherein the alkyl polyethylene glycol glycidyl ether compound and-NH in the chitosan₂The amount of the substance(s) in (b) is in the ratio R_EP0.001-2: 1;

and 3, protonating the chitosan-based comb type amphiphilic temperature-sensitive polymer solution containing the characteristic structure shown in the formula I or the formula III to obtain a protonated chitosan-based comb type amphiphilic temperature-sensitive polymer solution containing the characteristic structure shown in the formula II or the formula IV, and sequentially filtering, dialyzing, freezing and drying to obtain a protonated target product.

In the step 1, the deacetylation degree of the chitosan is more than or equal to 60%, and the viscosity of the chitosan is 5-1000 mPa & s.

In the step 1, the deacetylation degree of the chitosan is more than or equal to 90%, and the viscosity of the chitosan is 5-500 mPa & s.

In step 2, the added alkyl polyethylene glycol glycidyl ether compound is firstly dissolved in a water/isopropanol mixed solvent to form a mixed solution of the alkyl polyethylene glycol glycidyl ether compound, V_{Water (W)}/V _{Isopropanol (I-propanol)}3/7-7/3, wherein the concentration of the mixed solution of the alkyl polyethylene glycol glycidyl ether compound is 0.005-0.5 mol/L.

In step 3, the protonation reagent is at least one of hydrochloric acid, hydrobromic acid, hydroiodic acid, acetic acid, nitric acid, sulfuric acid and sulfurous acid, and protons in the reagent and-NH in the chitosan in step 1₂The amount of the substance(s) in (b) is in the ratio R_pIs 0.001-1: 1.

After the technical scheme is adopted, when the temperature is increased or reduced to the critical dissolution temperature within the range of 30-55 ℃, the chitosan-based comb type amphiphilic temperature-sensitive polymer and the protonated polymer thereof are prepared in waterThe dispersion-aggregation state in the solution will undergo a critical change, macroscopically expressed as the aqueous solution of the polymer from

Critical sudden change of (c); the microscopic expression is influenced by temperature change, the micelle diameter of the chitosan-based comb-type amphiphilic temperature-sensitive polymer is adjustable within the range of 120nm to 2000nm, and the chitosan-based comb-type amphiphilic temperature-sensitive polymer has the thermosensitive stimulation-response characteristic of the upper critical solution temperature. The polymer has potential application value in temperature-sensitive intelligent drug carriers, functional breathable textile fabrics and temperature-sensitive film materials.

Further, the invention relates to a preparation method of the chitosan-based comb-type amphiphilic temperature-sensitive polymer, which comprises the steps of regulating the viscosity of chitosan and the type and the dosage of an alkyl polyethylene glycol glycidyl ether compound at room temperature, and carrying out graft condensation reaction to obtain the chitosan-based comb-type amphiphilic temperature-sensitive polymer with a polymer chain structure containing a characteristic structure shown as a formula I or a formula III; the chitosan-based comb-type amphiphilic temperature-sensitive polymer containing protonation shown in formula II or formula IV in a polymer chain is further protonated, the preparation process is simple and easy to control, the reaction does not need heating, and the requirements of the industry of green chemistry and green process are met.

Drawings

FIG. 1 shows the preparation of chitosan and chitosan-based comb-type amphiphilic thermo-sensitive polymer in example 1¹HNMR; wherein curve b is of chitosan¹HNMR spectral line, curve a is that of chitosan-based comb type amphiphilic temperature-sensitive polymer¹HNMR spectral line;

FIG. 2 is a graph showing the relationship between the transmittance and the particle size of an aqueous solution of the chitosan-based comb-type amphiphilic temperature-sensitive polymer prepared in example 1 as a function of temperature;

fig. 3 is a drug release curve diagram of the chitosan-based comb-type amphiphilic temperature-sensitive polymer drug-loaded system with the upper critical solution temperature characteristic obtained in example 2 at different temperatures.

Detailed Description

A chitosan-based comb-type amphiphilic temperature-sensitive polymer is prepared by taking chitosan and alkyl polyethylene glycol glycidyl ether compounds as raw materials, wherein a polymer chain of the chitosan-based amphiphilic temperature-sensitive polymer contains at least one of characteristic structures shown in formulas I-IV:

in formula I, m1, m2 and m3 are integers respectively, and m2 is not zero,

the value of [ (m1+ m2)/(m1+ m2+ m3) ] x 100% is not more than the deacetylation degree of the chitosan, n1 is more than or equal to 4, n1 ' is more than or equal to 0 and less than or equal to 20, n2 is more than or equal to 9, n2 ' is more than or equal to 0 and less than or equal to 41, m is more than or equal to 3, and m ' is more than or equal to 0 and less than or equal to 80;

in formula II, m1, m2 and m3 are integers respectively, and m2 is not zero,

[(m1+m2)/(m1+m2+m3)]× 100% is not more than the deacetylation degree of chitosan, n1 is not less than 4, n1 ' is not less than 0 and not more than 20, n2 is not less than 9, n2 ' is not less than 0 and not more than 41, m is not less than 3, m ' is not less than 0 and not more than 80, y is an integer not more than 3, X^-＝Cl^-,Br^-,I^-,Ac^-,HSO₄ ^-,HSO₃ ^-,NO₃ ^-；

In formula III, m1, m2 and m3 are integers respectively, and m2 is not zero,

the value of [ (m1+ m2)/(m1+ m2+ m3) ] x 100% is not more than the deacetylation degree of the chitosan, n1 is more than or equal to 4, n2 is more than or equal to 9, and m is more than or equal to 3;

in formula IV, m1, m2 and m3 are integers respectively, and m2 is not zero,

[(m1+m2)/(m1+m2+m3)]× 100% is not more than the deacetylation degree of chitosan, n1 is not less than 4, n2 is not less than 9, m is not less than 3, y is an integer not more than 3, X^-＝Cl^-,Br^-,I^-,Ac^-,HSO₄ ^-,HSO₃ ^-,NO₃ ^-。

To further illustrate the technical solution of the present invention, the following description is given of specific embodiments.

Preparation of chitosan-based comb type amphiphilic temperature-sensitive polymer