CN104292475A - Temperature-sensitive and photosensitive dual-response polypeptide based host-guest composite intelligent hydrogel as well as preparation method and application thereof - Google Patents

Abstract

The invention discloses a temperature-sensitive and photosensitive dual-response polypeptide based host-guest composite intelligent hydrogel and a preparation method thereof. The preparation method comprises the following steps: dissolving a graft polymer PELG-g-(PNIPAM/beta-CD) modified by poly(N-isopropylacrylamide) and beta-cyclodextrin together and second generation dendritic molecules (Me-G2-Azo) modified by azobenzene into water, and mixing to prepare a sol. The temperature-sensitive and photosensitive dual-response polypeptide based host-guest composite intelligent hydrogel disclosed by the invention has stimulation response properties to temperature and light, is easy to prepare, and has wide application prospects in the fields of temperature control and optical control switches, temperature control and optical control motors and temperature control and optical control medicament release.

Description

A temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite intelligent hydrogel and its preparation method and application

technical field

The invention belongs to the technical field of new materials, specifically relates to an intelligent polymer material technology, and more specifically relates to a temperature-sensitive and photosensitive double-responsive polypeptide-based host-guest composite intelligent hydrogel and its preparation method and application.

Background technique

Hydrogel is a very important class of soft matter materials, which has broad application prospects in various fields, and the research on hydrogel has attracted more and more attention from researchers in recent years. Cyclodextrin supramolecular hydrogel is a new research field in recent years. In addition to the basic properties of general hydrogels, such as biocompatibility, high water content, and non-inactivation of drug loading, it also has unique self-assembly and molecular recognition properties, showing good intelligent responsiveness, such as temperature , light, pH value and other stimuli responsiveness, so it will greatly promote the research and application of traditional hydrogels. By designing and regulating cyclodextrin derivatives and guest molecules, the structure and intelligence of supramolecular hydrogels can be controlled to meet the application requirements in different fields. Li Li and others grafted α-cyclodextrin and monoamino-substituted azobenzene onto polyacrylic acid, and then compounded the two, using the inclusion ability of cyclodextrin and the photosensitive properties of azobenzene to prepare A photosensitive hydrogel system with sol-gel phase transition behavior (Chinese patent application: 201110359858.3). However, this hydrogel system is a single-stimuli-responsive smart hydrogel that responds to light stimuli, and the interconversion effect between sol-gel is not obvious enough macroscopically, and the biocompatibility of the system is not good enough. .

Contents of the invention

Aiming at the deficiencies of the prior art, the present invention proposes a new temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite smart hydrogel, which is a new type of dual-stimuli-responsive smart hydrogel with Obvious temperature sensitivity and good photosensitivity, and has good biocompatibility.

The temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite intelligent hydrogel proposed by the present invention refers to a host-guest composite intelligent hydrogel system containing a polypeptide, which includes a grafted polymer PELG-g-(PNIPAM/β- CD) and azobenzene-modified second-generation dendrimers (Me-G ₂ -Azo).

In the present invention, the water-soluble dendritic molecule Me-G ₂ -Azo is a dendritic molecule with azo at the top and methyl at the end, and has good photosensitivity and temperature sensitivity (for example, its phase transition temperature is between around 60°C). In the present invention, the water-soluble dendritic molecule Me-G ₂ -Azo is a compound with a novel structure, and its chemical structural formula is shown in the following formula (1):

In the present invention, the graft polymer PELG-g-(PNIPAM/β-CD) is a graft polymer whose side chain is modified jointly by poly(N-isopropylacrylamide) and β-cyclodextrin. The chemical structural formula is as shown in the following formula (2):

Wherein, the concentration of the grafted polymer PELG-g-(PNIPAM/β-CD) and the azobenzene-modified second-generation dendrimer (Me-G ₂ -Azo) in the aqueous solution should not be lower than 0.05 g/ml.

The temperature-sensitive and photosensitive double-responsive polypeptide-based host-guest composite intelligent hydrogel of the present invention is a thermosensitive and photosensitive double-responsive hydrogel, including stimulus responsiveness to temperature and stimulus responsiveness to light; it has good biological Compatibility and other beneficial effects.

The temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite intelligent hydrogel of the present invention, when the temperature rises to 40°C, the sol transforms into a hydrogel, and when the temperature returns to room temperature, the gel is destroyed and returns to the sol state; when the temperature rises When the temperature reached 60°C, precipitation appeared at the bottom, and no gel could be formed. When the temperature returned to room temperature, the system turned into a sol again.

The temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite intelligent hydrogel of the present invention is heated to 40°C to form a hydrogel, and the temperature is kept constant. After irradiating it with ultraviolet light with a wavelength of 365nm, it will be placed in the dark for a while. A gel-sol transition occurs; then the sol formed is irradiated with visible light with a wavelength of 450nm, and the gel recovers again after standing still.

The present invention also proposes a new compound, which is a water-soluble azobenzene-modified dendritic molecule Me-G ₂ -Az, which is a dendritic molecule with azo at the top and methyl at the end, and its chemical structural formula is as follows: Formula (1) shows:

The invention also provides a method for preparing a temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite intelligent hydrogel, a graft polymer PELG co-modified with poly(N-isopropylacrylamide) and β-cyclodextrin -g-(PNIPAM/β-CD) and azobenzene-modified second-generation dendrimer (Me-G ₂ -Azo) were dissolved in water and mixed to prepare a sol.

The preparation method of the present invention comprises the following steps:

In the first step, using L-glutamic acid and chloroethanol as initial raw materials, the grafted polymer was prepared by NCA (α-amino acid-N-carboxy internal acid anhydride) ring-opening polymerization, azidation reaction and click chemical reaction. PELG-g-(PNIPAM/β-CD), its molecular structure is shown in formula (2);

In the second step, the graft polymer PELG-g-(PNIPAM/β-CD) of the above-mentioned poly(N-isopropylacrylamide) and β-cyclodextrin modified together with the formula (1 The azobenzene-modified second-generation dendrimer (Me-G ₂ -Azo) shown in ) is dissolved in water and mixed to prepare a sol; further, by adjusting the temperature change and/or adjusting the light change, a temperature-sensitive and photosensitive double-response Polypeptide-based host-guest composite smart hydrogel.

In the present invention, the temperature-sensitive responsive polypeptide-based host-guest composite smart hydrogel is prepared by adjusting the temperature change from the sol obtained in the second step above. Wherein, the temperature adjustment is carried out in the form of a constant temperature water bath; the sol is prepared at room temperature, and when the temperature is raised to 40°C, the sol is transformed into a hydrogel, and the temperature returns to room temperature, and the gel is destroyed and returns to the sol state; When the temperature rose to 60°C, precipitation appeared at the bottom and no gel could be formed. When the temperature returned to room temperature, the system turned into a sol again.

In the present invention, the temperature of the sol system obtained in the second step above is raised to 40°C to form a hydrogel, and the temperature is kept constant. The said adjustment of light changes means that the photosensitivity-responsive polypeptidyl main body is prepared by alternately irradiating ultraviolet light and visible light. Guest complex smart hydrogels. Wherein, the alternating irradiation of ultraviolet light and visible light is to irradiate the gel with ultraviolet light with a wavelength of 365nm until it returns to a sol state, and then irradiate with visible light with a wavelength of 450nm until it turns into a gel.

The temperature-sensitive and photosensitive-responsive polypeptide-based host-guest composite smart hydrogel prepared by the invention can realize the effect of temperature-sensitive and photosensitive double-stimuli response of the smart hydrogel.

In the present invention, the graft polymer PELG-g-(PNIPAM/β-CD) is prepared in the following manner: using L-glutamic acid and chlorohydrin as starting materials through NCA (α-amino acid-N-carboxyl endo Anhydride) ring-opening polymerization and azidation reaction to prepare PELG with azide side group, and then click chemical reaction (Click) to pre-prepared PNIPAM (poly N-isopropylacrylamide) with alkyne terminal group and Alkyne-based cyclodextrin functional molecules were grafted onto the main chain of PELG to obtain the target product: PELG-g-(PNIPAM/β-CD), a graft polymer co-modified by PNIPAM and β-CD. Wherein, the poly-N-isopropylacrylamide (PNIPAM) is prepared by atom transfer radical polymerization (ATRP).

Specifically, the preparation method of the temperature-sensitive and photosensitive dual-responsive polypeptide-based host-guest composite intelligent hydrogel of the present invention includes: the graft polymer PELG co-modified with poly(N-isopropylacrylamide) and β-cyclodextrin -g-(PNIPAM/β-CD) and azobenzene-modified second-generation dendrimer (Me-G ₂ -Azo) were dissolved in water and mixed to prepare a sol. On the one hand, when the temperature rises to 40 °C, the sol transforms into a hydrogel, and when the temperature returns to room temperature, the gel breaks and returns to the sol state. When the temperature rises to 60°C, precipitation appears at the bottom, and the gel cannot be formed. When the temperature returns to room temperature, the system turns into a sol again, thereby preparing a temperature-sensitive responsive polypeptide-based host-guest composite smart hydrogel; on the other hand, the The system was heated up to 40°C to form a hydrogel, and the temperature was kept constant. After the system was irradiated with ultraviolet light with a wavelength of 365nm, gel-sol transition would occur when placed in the dark. Then, visible light with a wavelength of 450nm is used to irradiate the formed sol, and the gel recovers again after standing still, and the invention has better temperature sensitivity and photosensitivity. In this way, a novel temperature- and light-controllable polypeptide-based host-guest composite intelligent hydrogel system was prepared.

In one embodiment of the present invention, after the sol is obtained, the temperature of the system is raised to 40° C. until the sol turns into a hydrogel, the temperature returns to room temperature, and the gel breaks and returns to the sol state. When the temperature of the system rises to 60°C, precipitation occurs at the bottom, and no gel can be formed. When the temperature returns to room temperature, the system turns into a sol again, and the temperature-sensitive stimulus-responsive polypeptide-based host-guest composite smart hydrogel is obtained. During the implementation of the present invention, the hydrogels obtained by changing the sequence of increasing temperature and decreasing temperature all have good temperature-sensitive properties. And repeated implementation of the present invention to raise the temperature and then lower the temperature 20 times, the hydrogel still maintains good temperature-sensitive properties.

In one embodiment of the present invention, after the system is heated to 40°C to obtain a hydrogel, the gel is irradiated with ultraviolet light with a wavelength of 365nm until it returns to the sol state, and then irradiated with visible light with a wavelength of 450nm until it transforms into gel to obtain the light-sensitive stimulus-responsive polypeptidyl host-guest composite intelligent hydrogel. During the implementation of the present invention, the hydrogels obtained by changing the irradiation mode of ultraviolet light and visible light all have good photosensitivity. And repeating the alternate irradiation of ultraviolet light and visible light of the present invention up to 20 times, the hydrogel still maintains good photosensitivity.

In a specific embodiment, the method for preparing the temperature-sensitive and photosensitive double-responsive polypeptide-based host-guest composite intelligent hydrogel of the present invention specifically includes the following steps:

(1) Preparation of graft polymer PELG-g-(PNIPAM/β-CD):

Using L-glutamic acid and chloroethanol as initial raw materials, PELG with side groups as azido groups was prepared by NCA (α-amino acid-N-carboxyl internal acid anhydride) ring-opening polymerization and azidation reaction, and then click chemical reaction was used. In a 50mL reaction flask, add pre-prepared poly N-isopropylacrylamide (PNIPAM) (1.00g, 0.238mmol) containing alkyne end groups, cyclodextrin functional molecules with alkyne groups (mono-6-Propargyl-β- CD) (0.12g, 0.102mmol), PELG-N ₃ (0.052g) and 10mL DMF, stirred evenly, and then added CuBr (0.041g, 0.28mmol) and ligand PMDETA (60μL) under the protection of nitrogen atmosphere. Keep the reaction at 50°C for 72 hours. The reaction was stopped, DMF was spin-dried, dichloromethane was added, the organic phase was concentrated, precipitated in ether, filtered by suction, and collected by vacuum drying to obtain 0.91 g of white solid powder with a yield of 77.8%. The graft polymer PELG-g-(PNIPAM/β-CD) is a graft polymer whose side chain is modified jointly by poly(N-isopropylacrylamide) and β-cyclodextrin, step (1) The reaction scheme is as follows:

(2) Preparation of temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite smart hydrogel:

The graft polymer PELG-g-(PNIPAM/β-CD) prepared in step (1) and the azobenzene-modified second-generation dendritic molecule (Me-G2-Azo) were dissolved in water and mixed to prepare a sol. On the one hand, when the temperature rises to 40°C, the sol turns into a hydrogel, and when the temperature returns to room temperature, the system returns to the sol state. When the temperature rises to 60°C, no gel can be formed, and the temperature returns to room temperature, the system turns into a sol again, and the temperature-sensitive responsive polypeptide-based host-guest composite smart hydrogel is obtained; on the other hand, the system is heated to 40 ℃ to form a hydrogel, keep the temperature constant, and after it is irradiated with ultraviolet light with a wavelength of 365nm, a gel-sol transition occurs. Visible light with a wavelength of 450nm is then used to irradiate the formed sol, and gel recovery occurs again, and the photosensitive responsive polypeptide-based host-guest composite intelligent hydrogel system is obtained.

In the preparation method of the present invention, the concentration of the grafted polymer PELG-g-(PNIPAM/β-CD) and the second-generation dendritic molecule (Me-G ₂ -Azo) modified by azobenzene in the aqueous solution shall not be lower than 0.05g /ml.

Wherein, the cyclodextrin is β-cyclodextrin.

Wherein, the molar ratio of poly N-isopropylacrylamide (PNIPAM) containing alkyne end group to cyclodextrin functional molecule (mono-6-Propargyl-β-CD) with alkyne group is 1:1.2～1.5 .

Wherein, the precipitating agent used in the click chemical reaction for preparing the graft polymer is diethyl ether.

The invention also proposes the temperature-sensitive and photosensitive-responsive polypeptide-based host-guest composite intelligent hydrogel obtained by the above-mentioned preparation method.

The invention also proposes the application of the temperature-sensitive and photosensitive double-response polypeptide-based host-guest composite intelligent hydrogel in the fields of light-controlled motors, light-controlled switches, and light-controlled drug release.

The beneficial effects of the present invention include that a new type of temperature-sensitive dendrimer is prepared by using the inclusion characteristics of cyclodextrin, the photoisomerization characteristics of azobenzene, and the good temperature-sensitive properties of the second-generation dendrimers modified by azobenzene and PNIPAM. Photosensitive dual-response polypeptide-based host-guest composite intelligent hydrogel system. The preparation method of the hydrogel is simple and easy to control, and the synthesized graft polymer has unique structure, good biocompatibility and low biotoxicity. The hydrogel prepared by this method has good dual-stimulus responsiveness to temperature and ultraviolet-visible light. The hydrogel of the invention has a wide range of applications, and has broad application prospects in optical elements such as light-controlled motors, light-controlled switches, and light-controlled drug release.

Description of drawings

Fig. 1 is the nuclear magnetic hydrogen spectrum of the graft polymer PELG-g-(PNIPAM/β-CD) that embodiment 1 prepares.

Fig. 2 is a scanning electron micrograph of the temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite smart hydrogel in Example 3.

Fig. 3 is the G ', G " and viscosity of the temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite intelligent hydrogel in Example 3 as a function of scanning frequency; Fig. 3A shows the energy storage mode of the hydrogel in the entire test frequency range The amount (G') is much greater than the loss modulus (G"), which confirms the formation of the gel system of the present invention; Figure 3B shows that the viscosity of the gel increases with the increase of the shear frequency, proving that it has shear Thickening properties.

Detailed ways

The present invention will be described in further detail in conjunction with the following specific examples and accompanying drawings, and the protection content of the present invention is not limited to the following examples. Without departing from the spirit and scope of the inventive concept, changes and advantages conceivable by those skilled in the art are all included in the present invention, and the appended claims are the protection scope. The process, conditions, reagents, experimental methods, etc. for implementing the present invention are general knowledge and common knowledge in the art except for the content specifically mentioned below, and the present invention has no special limitation content.

A method for preparing a temperature-sensitive and photosensitive-responsive polypeptide-based host-guest composite intelligent hydrogel of the present invention comprises the following steps:

(1) Preparation of graft polymer PELG-g-(PNIPAM/β-CD)

Using L-glutamic acid and chloroethanol as initial raw materials, PELG-N ₃ with side groups as azido groups was prepared by NCA (α-amino acid-N-carboxyl internal acid anhydride) ring-opening polymerization and azidation reaction, and then click Chemical reaction, add pre-prepared poly N-isopropylacrylamide (PNIPAM) (1.00g, 0.238mmol) containing alkyne terminal group, cyclodextrin functional molecule (mono-6-Propargyl -β-CD) (0.12g, 0.102mmol), PELG-N3 (0.052g) and 10mL DMF, stirred evenly, then added CuBr (0.041g, 0.28mmol) and ligand PMDETA (60μL) under the protection of nitrogen atmosphere. Keep the reaction at 50°C for 72 hours. The reaction was stopped, DMF was spin-dried, dichloromethane was added, the organic phase was concentrated, precipitated in ether, filtered by suction, and collected by vacuum drying to obtain 0.91 g of white solid powder with a yield of 77.8%. Finally, the target product side chain is poly(N-isopropylacrylamide) and β-cyclodextrin modified graft polymer PELG-g-(PNIPAM/β-CD).

Wherein, the molar ratio of poly N-isopropylacrylamide (PNIPAM) with alkyne end group to cyclodextrin functional molecule (mono-6-Propargyl-β-CD) with alkyne group is 1:1.2-1.5.

Wherein, the precipitating agent used in the click chemical reaction for preparing the grafted polymer is diethyl ether.

The graft polymer PELG-g-(PNIPAM/β-CD) prepared in step (1) is a graft polymer co-modified by poly(N-isopropylacrylamide) and β-cyclodextrin.

(2) Preparation of temperature-sensitive and photosensitive double-responsive peptide-based host-guest composite smart hydrogel

A sol was prepared by dissolving the graft polymer PELG-g-(PNIPAM/β-CD) and the azobenzene-modified second-generation dendrimer (Me-G ₂ -Azo) in water and mixing them. On the one hand, when the temperature rises to 40 °C, the sol transforms into a hydrogel, and when the temperature returns to room temperature, the gel breaks and returns to the sol state. When the temperature rises to 60°C, precipitation appears at the bottom, and the gel cannot be formed. When the temperature returns to room temperature, the system turns into a sol again, thereby preparing a temperature-sensitive responsive polypeptide-based host-guest composite smart hydrogel; on the other hand, the The system was heated up to 40°C to form a hydrogel, and the temperature was kept constant. After the system was irradiated with ultraviolet light with a wavelength of 365nm, gel-sol transition would occur when placed in the dark. Then, visible light with a wavelength of 450nm is used to irradiate the formed sol, and the gel recovers again after standing still, and the invention has better temperature sensitivity and photosensitivity. In this way, a novel temperature- and light-controllable polypeptide-based host-guest composite intelligent hydrogel system was prepared.

The prepared temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite smart hydrogel is a dual-stimuli-responsive smart hydrogel, including dual-stimuli response properties of temperature and light. Wherein, the concentration of the grafted polymer PELG-g-(PNIPAM/β-CD) and the azobenzene-modified second-generation dendrimer (Me-G ₂ -Azo) in the aqueous solution should not be lower than 0.05 g/ml.

Embodiment 1 prepares graft polymer PELG-g-(PNIPAM/β-CD)

The preparation process of this embodiment is as shown in the following formula (3):

Using L-glutamic acid and chloroethanol as initial raw materials, PELG-N ₃ with side groups as azido groups was prepared by NCA (α-amino acid-N-carboxyl internal acid anhydride) ring-opening polymerization and azidation reaction, and then click Chemical reaction, add pre-prepared poly N-isopropylacrylamide (PNIPAM) (1.00g, 0.238mmol) containing alkyne terminal group, cyclodextrin functional molecule (mono-6-Propargyl -β-CD) (0.12g, 0.102mmol), PELG-N3 (0.052g) and 10mL DMF, stirred evenly, then added CuBr (0.041g, 0.28mmol) and ligand PMDETA (60μL) under the protection of nitrogen atmosphere. Keep the reaction at 50°C for 72 hours. The reaction was stopped, DMF was spin-dried, dichloromethane was added, the organic phase was concentrated, precipitated in ether, filtered by suction, and collected by vacuum drying to obtain 0.91 g of white solid powder with a yield of 77.8%. Finally, the target product side chain is poly(N-isopropylacrylamide) and β-cyclodextrin modified graft polymer PELG-g-(PNIPAM/β-CD). ¹ H-NMR (CDCl ₃ , δ): As can be seen from the proton nuclear magnetic spectrum, the peak signal of 6.49ppm is the signal peak (a) of the hydrogen proton of -NH- in PNIPAM on the grafted polymer, and at 4.60ppm At 4.05ppm is the signal peak of H and -COCH ₂ CH ₂ -(c) on the 6 and 7 hydroxyl groups of the polypeptide side chain β-cyclodextrin, and at 4.05ppm is the signal peak of -CH-CO-(e) and The signal peak of -NH-CH-(i) on the side chain PNIPAM, the signal peak of H on the 3-position carbon of the polypeptide side chain group β-cyclodextrin and -COCH ₂ CH ₂ -(b) appeared at 3.75ppm , and at the same time, the hydrogen proton signal peaks of the 2, 4, 5, and 6 positions of β-cyclodextrin appeared at 3.10.

The nuclear magnetic spectrum of the product of this example is shown in Figure 1. It can be seen that the graft polymer PELG-g-(PNIPAM /β-CD).

Example 2 Preparation of temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite smart hydrogel

The graft polymer PELG-g-(PNIPAM/β-CD) prepared in Example 1 and the azobenzene-modified second-generation dendritic molecule (Me-G ₂ -Azo) were dissolved in water and mixed to prepare a sol. When the temperature of the system rises to 40°C, the sol turns into a hydrogel, and when the temperature returns to room temperature, the gel breaks and returns to the sol state. When the temperature of the system rises to 60°C, precipitation occurs at the bottom, and no gel can be formed. When the temperature returns to room temperature, the system turns into a sol again, and the temperature-sensitive stimulus-responsive polypeptide-based host-guest composite smart hydrogel is obtained. The method for identifying the obtained photosensitive hydrogel is: invert the sample bottle for 5 minutes, the system can overcome the gravity and be in a stable state without any flow, thus confirming the formation of the temperature-sensitive stimulus-responsive polypeptidyl main body of the present invention. Guest complex smart hydrogels.

After the system was heated to 40°C to obtain a hydrogel, the gel was irradiated with ultraviolet light with a wavelength of 365nm to return to the sol state, and then irradiated with visible light with a wavelength of 450nm, the system transformed into a gel, and the photosensitized stimulus was obtained. Responsive polypeptide-based host-guest composite smart hydrogels are shown. The method for identifying the obtained photosensitive hydrogel is as follows: invert the sample bottle for 5 minutes, the system can overcome gravity and be in a stable state without any flow, thus confirming that the photosensitive stimulus-responsive polypeptide-based host-guest of the present invention has been formed. Composite smart hydrogel.

Example 3 Relevant characterization of temperature-sensitive and photosensitive dual-response polypeptide-based host-guest composite smart hydrogel

Figure 2 shows the SEM photos of the formed polypeptide-based host-guest composite smart hydrogel. After freeze-drying, the hydrogel presents a continuous porous structure with a pore size of about 10 μm. It can be seen from the figure that there is a certain degree of fragmentation and collapse, which may be related to the influence of physical cross-linking force.

In addition, the present invention also characterizes the viscoelastic behavior of the host-guest composite smart hydrogel through dynamic mechanical property tests, as shown in FIG. 3 . Just like the viscoelastic gel system reported in the literature, the dynamic frequency sweep of the system through the rheometer shows that the storage modulus (G′) of the hydrogel is much greater than the loss modulus (G″) in the entire test frequency range ), which has just confirmed the formation of the gel system of the present invention. And it can be proved that the host-guest composite intelligent hydrogel constructed by the present invention has better mechanical properties, so it is beneficial as a tissue engineering scaffold, etc. On the other hand, it can be seen , the viscosity of the hydrogel increases with the increase of the shear frequency, which proves that it has the property of shear thickening, and proves that the host-guest composite system of the present invention belongs to the expansion-plastic fluid.

Claims (10)

1. temperature sensitive photosensitive double-bang firecracker should gather a peptidyl Subjective and Objective composite intelligent hydrogel, it is characterized in that, it comprises the two generation dendrimer Me-G that graftomer PELG-g-(PNIPAM/ β-CD) modifies with nitrogen benzide ₂-Azo; Wherein, two generation dendrimer Me-G of described nitrogen benzide modification ₂-Azo is such as formula shown in (1):

Described graftomer PELG-g-(PNIPAM/ β-CD) is such as formula shown in (2):

2. temperature sensitive photosensitive double-bang firecracker as claimed in claim 1 should gather peptidyl Subjective and Objective composite intelligent hydrogel, it is characterized in that, the two generation dendrimer Me-G that described graftomer PELG-g-(PNIPAM/ β-CD) and described nitrogen benzide are modified ₂-Azo concentration in aqueous must not lower than 0.05g/ml.

3. temperature sensitive photosensitive double-bang firecracker as claimed in claim 1 should gather peptidyl Subjective and Objective composite intelligent hydrogel, it is characterized in that, when temperature is increased to 40 DEG C, colloidal sol changes hydrogel into, and temperature is returned to room temperature, and gel breaks down returns back to collosol state; When temperature rises to 60 DEG C, there is precipitation in bottom, can not form gel, temperature returns back to room temperature, and system changes colloidal sol into again.

4. temperature sensitive photosensitive double-bang firecracker as claimed in claim 1 should gather peptidyl Subjective and Objective composite intelligent hydrogel, it is characterized in that, be warming up to 40 DEG C and form hydrogel, keep temperature-resistant, adopt wavelength to be the UV-light of 365nm after it irradiates, lucifuge is placed and be there will be gel-sol conversion; Adopt again wavelength be 450nm visible ray to formed colloidal sol irradiate, leave standstill again there is gel back.

5. temperature sensitive photosensitive double-bang firecracker should gather a preparation method for peptidyl Subjective and Objective composite intelligent hydrogel, it is characterized in that, comprises the steps:

The first step: with Pidolidone and chloroethanol for initial feed, successively by NCA (a-amino acid-N-carboxyl inner-acid anhydride) ring-opening polymerization, azido reaction and click chemistry reaction, prepare the graftomer PELG-g-(PNIPAM/ β-CD) shown in formula (2);

Second step: the two generation dendrimer Me-G that the graftomer PELG-g-(PNIPAM/ β-CD) above-mentioned obtained NIPA and beta-cyclodextrin jointly modified and the nitrogen benzide shown in formula (1) are modified ₂soluble in water being mixed with of-Azo obtains colloidal sol, by regulating temperature variation and/or regulating illumination change, obtaining temperature sensitive photosensitive double-bang firecracker as claimed in claim 1 and should gather peptidyl Subjective and Objective composite intelligent hydrogel.

6. preparation method as claimed in claim 5, is characterized in that, the colloidal sol that described second step obtains, by regulating temperature variation, obtains temperature sensitive responsiveness and gathers peptidyl Subjective and Objective composite intelligent hydrogel; Wherein, described adjustment temperature variation is carried out with the form of water bath with thermostatic control; Obtained colloidal sol under room temperature, during raised temperature to 40 DEG C, colloidal sol changes hydrogel into, and temperature is returned to room temperature, and gel breaks down returns back to collosol state; When temperature rises to 60 DEG C, there is precipitation in bottom, can not form gel, temperature returns back to room temperature, and system changes colloidal sol into again.

7. preparation method as claimed in claim 5, it is characterized in that, described regulating illumination change refers to the colloidal sol obtained by described second step, be warming up to 40 DEG C and form hydrogel, keep temperature-resistant, by replacing irradiating ultraviolet light and visible ray, obtaining photosensitive response and gathering peptidyl Subjective and Objective composite intelligent hydrogel; Wherein, described alternately irradiating ultraviolet light and visible ray are that the UV-light of 365nm is irradiated until return back to collosol state described gel with wavelength, then be that the radiation of visible light of 450nm is until be transformed into gel with wavelength.

8. the temperature sensitive photosensitive response prepared by method described in claim 5 gathers peptidyl Subjective and Objective composite intelligent hydrogel.

9. temperature sensitive photosensitive response as claimed in claim 1 gathers the application of peptidyl Subjective and Objective composite intelligent hydrogel in the light-operated motor of preparation, photoswitch, light-operated medicine.

10. the dendrimer Me-G of a water-soluble azo benzene modification ₂-Azo, is characterized in that, it is top is azo, end is the dendrimer of methyl, and its chemical structural formula is such as formula shown in (1):