JP2002060436A - Thermoresponsive polymer having capability of forming coacervate, and liquid-liquid phase partition process, immobilized enzyme and drug releasing agent using all using the polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermoresponsive polymer which exhibits such upper critical solution temperature (UCST) characteristics that it agglomerates in an aqueous solution by lowering the temperature and which has a capability of forming a coacervate, and to provide a liquid-liquid phase partition process, and to obtain an immobilized enzyme and a drug releasing agent using the polymer. SOLUTION: The thermorespnsive polymer contains a specified monomer as the constituent, exhibits upper critical solution temperature characteristics in an aqueous solution, and has a capability of forming a coacervate. The polymer is used for a liquid-liquid phase partition process, an immobilized enzyme and a drug releasing agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoresponsive polymer having a coacervate forming ability and a liquid-liquid phase partitioning method, an immobilized enzyme and a drug releasing agent using the same.

[0002]

2. Description of the Related Art In recent years, stimulus-responsive polymers have been widely applied to drug delivery systems (DDS), various separating agents, catheters, artificial muscles, chemovalves, and the like, and their importance has been rapidly increasing. For example, Japanese Patent Application Laid-Open No. 8-103653 describes a stimuli-responsive polymer, which is a polymer that changes its higher-order structure due to heat, pH, potential, light, and swells or shrinks in an aqueous solution. Derivatives of acrylamide such as N-isopropylacrylamide, N, N-diethylacrylamide, and vinyl ethers such as polymethyl vinyl ether are described. However, polymeric compounds known to swell-shrink in response to these temperature changes, although described as having an upper critical solution temperature (UCST) or lower critical solution temperature (LCST), are in fact all LCSTs.
Is a polymer having In other words, reversibly cause aggregation between polymers at a certain temperature or higher and become insoluble in water,
Above that, it had the property of dissolving in water. Thermoresponsive polymers that have LCST in aqueous solution and have the ability to form temperature-sensitive coacervates have been synthesized using dimethylacrylamide and phenylacrylamide copolymers (Preprints of the Society of Polymer Science (1994) Vol.43, p784).

[0003] Since a polymer compound having an LCST is a substance in which a polymer shrinks at a certain temperature or higher and becomes insoluble in water, it is desired that the shrinkage be performed at a low temperature at a low temperature when applied to a separating agent or the like. There was a problem that the adjustment was difficult in response to the request. When used as a separating agent for heat-unstable proteins and the like, the macromolecules are aggregated by a temperature-raising operation, so that the risk of denaturation of the protein by the operation must be considered. When the drug is encapsulated in the gel having the LCST and used as a DDS, it swells at a low temperature and releases the drug, so that it is necessary to cool the diseased part when releasing the drug. However, in practice, it is easier to raise the temperature of the diseased part.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems. The object of the present invention is to exhibit an upper critical solution temperature (UCST) characteristic of coagulation by a temperature lowering operation in an aqueous solution and to have a coacervate forming ability. An object of the present invention is to provide a thermoresponsive polymer and a liquid-liquid phase partitioning method, an immobilized enzyme and a drug releasing agent using the same.

[0005]

The present inventors have made intensive efforts to solve the above-mentioned problems, and as a result, a thermoresponsive polymer having an upper critical solution temperature characteristic in an aqueous solution and having a coacervate forming ability. I came to find.

That is, the present invention has the following constitution. (1) A thermoresponsive polymer containing as at least one kind of monomer component represented by the following general formula (1), exhibiting an upper critical solution temperature characteristic in an aqueous solution, and having a coacervate forming ability. .

[0007]

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(In the formula (1), R ₁ represents a hydrogen atom or a methyl group, and R ₂ represents a single bond or a linear or branched alkylene group having 1 to 5 carbon atoms.) (2) Hydrophilic (1) The thermoresponsive polymer according to the above (1), further comprising a hydrophilic monomer or a hydrophobic monomer as a copolymerization component. (3) The thermoresponsive polymer according to the above (1) or (2), further comprising a ligand molecule monomer as a copolymerization component. (4) A liquid-liquid phase partitioning method comprising a step of bringing an object to be separated into contact with the thermoresponsive polymer according to any one of the above (1) to (3) in an aqueous solvent. (5) An immobilized enzyme, wherein the enzyme is immobilized on the thermoresponsive polymer according to any one of (1) to (3). (6) A drug release agent comprising the thermoresponsive polymer according to any one of (1) to (3).

[0009]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for preparing UCST in an aqueous solution.
Provided is a thermoresponsive polymer (hereinafter, also referred to as UCST-CV polymer) having specific properties and a specific structure capable of forming coacervate. In the present invention, the aqueous solution is
It refers to water, a solvent mainly composed of water, for example, a solution such as a physiological saline solution or a buffer solution. The UCST-CV polymer of the present invention is a polymer contained as at least one kind of monomer component represented by the following general formula (1) (hereinafter, referred to as monomer (1)).

[0010]

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In the formula (1), R ₁ represents a hydrogen atom or a methyl group, and R ₂ represents a single bond or a group having 1 to 5, preferably 1 to 5 carbon atoms.
3 represents a linear or branched alkylene group. R ₂ is preferably a methylene group.

The UCST-CV polymer is prepared by synthesizing a hydrophilic monomer or a hydrophobic monomer (hereinafter, also referred to as monomer (2)) described later as another copolymerization component. Can be used as long as it can have. U of the present invention
The effect of copolymerization with the monomer (2) in the CST-CV polymer is that the temperature at which the formed coacervate dissolves can be arbitrarily changed. The charging ratio of the monomer (2) is 0.1 to 5 with respect to the monomer (1).
It is preferably about 0% by mass, more preferably 0.5% by mass.
% To 10% by mass.

In the present invention, the monomer (2) which can be contained as a copolymer component of the UCST-CV polymer is:
Although it cannot be said unconditionally because it is hydrophilic and hydrophobic with respect to the monomer (1) component site, acrylic acid, methacrylic acid, acrylamide, methacrylamide and the like are used as the hydrophilic monomer, and acrylate esters and the like are used as the hydrophobic monomer. Examples thereof include methacrylic acid esters, vinyl chloride, vinylidene chloride, and styrene, which may be used alone or in combination as appropriate. UCS of the present invention
The T-CV polymer contains a ligand molecule monomer (hereinafter, also referred to as a monomer (3)) as a copolymer component as a copolymer with the monomer (1) or further as a copolymer with a hydrophilic or hydrophobic monomer. can do.
There is no particular problem with the chemical structure of the ligand molecule monomer as long as the polymer to be synthesized can have UCST properties and coacervate forming ability. Specific examples include a monomer component having a biotin moiety or an iminobiotin moiety, and a monomer containing a ligand defined below. As the monomer component having a biotin moiety or iminobiotin moiety, the following general formula (3)
And a monomer represented by the formula:

[0014]

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[0015]

In the formula (3), R ² represents a hydrogen atom or an alkyl group. R ³ and R ⁴ each independently represent a hydrogen atom, an alkyl group or an aryl group. T is an oxygen atom or = NH
Represents a group. W represents a single bond, a carbonyl group, a thiocarbonyl group or an alkylene group having 1 to 5 carbon atoms. U represents a single bond or an -NH- group. X is a single bond or carbon number 1
To 8 hydrocarbon bonds, oxygen atoms or -NH- groups. Y is a single bond or a carbonyl group, a thiocarbonyl group,
—NH group—, 1,2-dioxyethylene group or 1,
Shows a 2-diaminoethylene group. Z represents a single bond or a carbonyl group, a thiocarbonyl group, an alkylene group having 1 to 5 carbon atoms, an oxygen atom or a -NH- group. V represents a single bond or an alkylene group having 1 to 5 carbon atoms.

More specifically, the following (3A) to (3)
The polymerizable (imino) biotin derivative represented by C) is preferred.

[0018]

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In the general formulas (3A) to (3C), R ¹ represents a single bond or an alkylene group having 1 to 4 carbon atoms, and R ⁵ represents an alkylene group having 2 or 3 carbon atoms. X ¹ represents an oxygen atom or a sulfur atom, and X ^{2 to} X ⁵ each independently represent an oxygen atom or a —NH— group. T, R ² , R ³ and R ⁴ are each as defined in the above formula (3).

The polymerizable (imino) biotin derivative represented by the above general formula (3A) is generally prepared by appropriately removing the carboxyl hydroxyl group on the side chain of the (imino) biotin or the (imino) biotin derivative represented by the following general formula (a1). After conversion into a leaving group, the compound can be obtained by a condensation reaction with an acrylic derivative represented by the following general formula (a2).

[0021]

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The polymerizable (imino) biotin derivative represented by the above general formula (3B) can be obtained by converting the (imino) biotin derivative represented by the following general formula (b1) into a suitable acrylate agent (b2) (methacrylate agent) Including, for example, acrylic acid, acrylic acid chloride, acrylic acid anhydride, acrylate agent such as acryloxysuccinimide, methacrylic acid,
Methacrylic acid chloride, methacrylic anhydride, methacryloxylating agent such as methacryloxysuccinimide).

[0023]

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Here, the (imino) biotin derivative of the formula (b1) can be obtained by reducing the (imino) biotin of the formula (a1) or the (imino) biotin derivative with a suitable reducing agent (X ⁴ = oxygen). Atom)
Further, it can be obtained by converting the hydroxyl group of the alcohol compound into a functional group having a leaving group function, and then subjecting it to a substitution reaction with an amine derivative (X ⁴ = -NH-).

The polymerizable (imino) biotin derivative represented by the general formula (3C) is generally obtained by converting the (imino) biotin derivative represented by the following general formula (c1) into THF, DMS
Obtained by reacting with an isocyanate compound represented by the formula (c2) in an aprotic solvent such as O, ether, DMF, sometimes chloromethane, chloroform, ethyl acetate, acetone, aliphatic hydrocarbon, benzene, and toluene. Can be.

[0026]

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Particularly preferred polymerizable biotin monomers in the present invention include, for example, JP-A-11-215667.
A biotin methacrylamide derivative such as the formula (3a) described in the specification or a biotin derivative such as the formula (3b).

[0028]

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Such a ligand molecule monomer is UC
0.1 to the monomer (1) of the ST-CV polymer
It is used in a range of 10% by mass.

In the present invention, after the above-mentioned monomers are copolymerized, dialysis can be carried out in order to remove unreacted monomers and salts. Alternatively, the UCST-CV polymer of the present invention can be purified by lowering the temperature of the solution to UCST or lower, removing the coacervate layer, and then removing the aqueous layer.

The molecular weight of the UCST-CV polymer of the present invention is not particularly limited, and it is preferable that properties such as UCST characteristics and coacervate forming ability do not depend much on the molecular weight. In practice, usually the mass average molecular weight is between 500 and 100000
Degree, more preferably about 1,000 to 100,000. The UCST-CV polymer of the present invention has a specific temperature (UCST)
In the above, the solution is maintained in an aqueous solution, but has a property of insolubilizing at a temperature lower than the specific temperature and forming a coacervate. In the present invention, the coacervate formed from the UCST-CV polymer includes UCST-C in the coacervate droplet or in the coacervate layer.
V polymer concentration and UCST-C in other aqueous solvents
The difference from the V polymer concentration is preferably from 0.01 to 45% by mass, more preferably from 0.01 to 10% by mass.
Range.

The UCST-CV polymer preferably has at least its UCST characteristics unchanged even after immobilization of a ligand or the like described later and formation of a complex with the ligand. When this complex is formed, the ability to form a coacervate may or may not be maintained. In the present invention, the term “UCST-CV polymer” includes polymers in which a ligand or the like is immobilized. Further, it is preferable that the UCST-CV polymer maintain its thermal responsiveness even by repeated changes of dissolution and insolubilization. In the present invention, the UCS of the UCST-CV polymer is used.
T means that the polymer was dissolved in distilled water (2% by mass), the transmittance of 500 nm visible light was measured in a quartz cell while raising or lowering the temperature, and the visible light of the polymer clarified solution when the temperature was raised was measured. Is 100%, and the temperature at which the transmittance reaches 50% is obtained. However, even if the transmittance reaches 50% at a certain point, the temperature may be maintained at a value of 50% within a certain temperature range even if the temperature is further increased or decreased. The upper limit of this temperature range is called UCST at the time of temperature rise, and the lower limit is called UCST at the time of temperature fall. The difference between the two temperature ranges is called the switching range. The narrower this switching range is, the better. According to the present invention, the practical UCST switching range is 10 ° C. or less, preferably 0 ° C.
° C. UCST of UCST-CV polymer of the present invention
Is not particularly limited, when the UCST-CV polymer of the present invention is applied to a liquid-liquid partitioning method, an immobilized enzyme, a drug releasing agent, and the like, a preferred UCST is 0 to 50 ° C, and particularly preferably 0 to 50 ° C.
It is in the range of 40 ° C.

The UCST-CV polymer of the present invention can be applied to various uses or usages that can utilize the above characteristics. When the UCST-CV polymer of the present invention is applied to the liquid-liquid phase partitioning method, an object to be separated is dissolved in a UCST-CV polymer aqueous solution, and a coacervate layer formed when the solution temperature is lower than UCST. A difference occurs in the affinity of the object to be separated and the aqueous layer, and the separation is performed in either of them, and if necessary, the recovery rate of the object to be separated can be increased. The present invention is particularly suitable for separating / concentrating a substance to be separated having a binding property to the UCST-CV polymer. Preferable examples of such an object include dyes such as Cibacron Blue and Blue Dextran. For example, the separated matter distributed to the coacervate layer can be separated by dialysis of the coacervate layer. In addition, as the UCST-CV polymer applied to the liquid-liquid phase partitioning method of the present invention, not only a ligand in which a ligand described later is immobilized but also a polymer in which a ligand is immobilized and used as a separating agent may be used. In the case of the latter, there is an advantage that the range of types of the object to be separated can be increased.

The present invention can provide an immobilized enzyme by immobilizing the enzyme on the UCST-CV polymer. The immobilized enzyme of the present invention is a powerful element for constructing a calibration method such as an immunoassay method, a bioreactor, and the like. In this case, when using a copolymer derivative of a monomer in which biotin or iminobiotin is immobilized in the molecule as described above, it is not necessary to immobilize an antibody or the like by the formation of a covalent bond described below, and avidin- The use of biotin affinity can immobilize the avidin-immobilized enzyme, which is preferable.

Since avidin has four sites for recognizing biotin, one of the binding sites for avidin is replaced with UCS.
Using biotin which is used for immobilizing the T-CV polymer and immobilizing any of the following biotin-immobilized enzymes or biotin-immobilized antibodies or biotin-immobilized ligands such as heat shock protein on the remaining biotin-binding site. It has the advantage that any ligand can be immobilized and the range of application can be greatly expanded. Avidin as used herein includes streptavidin. Immobilization of one of a pair including at least a pair of binding sites known to perform a specific interaction such as affinity between avidin and biotin (hereinafter referred to as a ligand, but the other can also be a ligand) In this manner, the target substance or the target substance (preferably, drug, biomolecule, microorganism, etc.) having the other binding site can be easily bound to the ligand immobilized on the UCST-CV polymer by performing the solution cooling operation. A useful separating agent and the like that can be obtained can be obtained. It should be noted that, even if one of the pairs is the same ligand, the other does not necessarily have to be of the same type, and may be appropriately selected. Therefore, different types of molecules can be separated with the same ligand depending on the purpose.

The ligand includes a protein, a nucleic acid, a peptide, a sugar chain and the like, and at least one of them is immobilized. Further, two or more kinds of the same category can be used. Specifically, antigens, antibodies, molecular chaperones, bioproducts, sugar chains, lectins, protein A, protein G, avidin, biotin, DNA, RN
A, hormones, dyes, etc., substrates and products in enzyme reactions, competitive inhibitors, coenzymes, cells, artificial cells, microorganisms,
Synthetic polymers are also included. Specific examples of a set known to perform the above specific interaction include an antigen-antibody, an enzyme-substrate (inhibitor), and various physiologically active substances-receptors. These sets include not only natural molecules but also synthetic molecules-natural molecules and synthetic molecules-synthetic molecules. In addition, examples of the interaction include an electrostatic interaction, a hydrophobic interaction, a hydrogen bond, a van der Waals interaction, and the like, singly or in combination.

The present invention can also provide a drug release agent comprising a UCST-CV polymer. The drug release agent of the present invention uses a UCST-CV polymer as a carrier for a drug of a so-called drug delivery system (DDS), and comprises a UCST-CV polymer and an arbitrary drug. The drug-releasing agent of the present invention controls the response of the UCST-CV polymer to temperature or further to pH, etc., so that the reversible dissolution and insolubilization of the UCST-CV polymer causes disappearance / formation of coacervate or UCST-CV.
The release and retention of the drug can be controlled with the dissolution and insolubilization of the polymer. The drug-releasing agent of the present invention is suitably used in preparations that have been spotlighted as intelligent preparations for administering a drug as needed when needed. In the drug release agent of the present invention, the means for carrying or binding various drugs (for example, anti-cancer agents such as adreamycin and taxol) to the UCST-CV polymer is UC
A method of contacting a drug with a UCST-CV polymer under control of an aqueous solution of the ST-CV polymer, such as temperature and pH, may be mentioned. In this case, as a UCST-CV polymer,
A method using a ligand such as the above-described immobilized antibody and other modes usually used in the art can be applied.
Further, the drug in the drug release agent of the present invention is referred to as UCST-C.
The embodiment of the UCST-CV polymer supported or bonded to the V polymer is preferably the inside or the surface of the coacervate layer, but may be a solution phase. Further, the drug release agent of the present invention may be subjected to a secondary treatment such as being housed or carried in a capsule, sponge, gel or the like. The dosage form of the drug release agent of the present invention is also arbitrary, and is appropriately selected depending on the dosage form. For example, oral preparations, patches,
Injections and the like can be mentioned. The present invention uses a UCST-CV polymer prepared by selecting an appropriate ligand to separate various substances or microorganisms with higher sensitivity than before, calibration such as immunoassay, protein production control,
A bioreactor or the like can be constructed.

The binding of a target substance such as an immobilized enzyme or a drug releasing agent to a UCST-CV polymer by a liquid-liquid phase partitioning method, binding using an ion complex or a charge transfer complex, biochemical affinity, etc. Is preferred. The target substance or the target substance bound to the UCST-CV polymer of the present invention includes, for example, ● control of salt concentration, ● pH control, ● control of inhibitors and substrates, ● control of denaturants such as urea and SDS, ● The binding strength can be controlled by appropriately selecting or combining methods such as control of an organic solvent, metal ions, and temperature control, and thus the distribution rate, reaction rate, drug release rate, and the like can be controlled. In addition, U of various ligands
The immobilization to the CST-CV polymer is preferably a covalent bond in order to maintain the reproducibility of the UCST-CV polymer. However, the immobilization to an ion complex or a charge transfer complex, biochemical affinity, etc. The connection may be used. More specifically, when proteins such as antibodies and enzymes are bound to the UCST-CV polymer, proteins often have functional groups such as amino groups and carboxyl groups, and the reactivity of these functional groups is reduced. Use UCST
-The CV polymer can be bound to a protein.

For example, when an amino group of a protein is used, a carboxyl group can be introduced into the UCST-CV polymer, and an amide bond can be formed by the following reaction formula.

[0040]

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There are also a method using an aldehyde group and a method using an epoxy group as shown below.

[0042]

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When a carboxyl group of a protein is used, an amino group can be introduced into the UCST-CV polymer and an amide bond can be formed by the following reaction formula.

[0044]

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When an antibody is introduced into the UCST-CV polymer and allowed to bind to a protein as a target substance, p
It is preferable that H be carried out in a phosphoric acid or Tris buffer near neutrality. Further, the salt concentration can be appropriately set according to the purpose. Further, by combining magnetic particles with the UCST-CV polymer to form a composite and using a magnet or the like at the time of separation, the UCST-CV polymer to which the target substance or the target substance is bound can be more efficiently aggregated.

The UCST-CV polymer of the present invention is more specifically applied to test agents such as detection of bacteria and residual agricultural chemicals, application to diagnostic agents, separation of bioproducts such as microorganisms and organisms in cell culture, It can be used particularly effectively for activating and maintaining biological reaction functions by immobilizing enzymes, molecular chaperones, and the like.

[0047]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Example 1 Synthesis of N-acryloylbutanoic acid 9 parts by mass of acrylic acid chloride and 10 parts by mass of 3-aminobutanoic acid were added to 200 ml of a 1N (mol / l) aqueous sodium hydroxide solution while maintaining the solution temperature at 5 ° C. while stirring. , Dripping at the same time. After the completion of the dropwise addition, the mixture was allowed to react at room temperature for 2 hours.
And extract the organic layer. The organic layer was concentrated under reduced pressure at a temperature of 40 ° C. or lower, and the obtained residue was subjected to column chromatography on silica gel using ethyl acetate as a mobile phase to obtain a white crystalline compound. When the obtained compound was subjected to NMR and mass spectrometry, the target compound was well supported.

Example 2 Synthesis and Properties of Poly-N-acryloylbutanoic acid 5 parts of N-acryloylbutanoic acid was dissolved in 100 ml of dimethyl sulfoxide, and 0.05 parts by mass of AIBN was used as an initiator in a nitrogen atmosphere. The polymerization was carried out for 3 hours. After completion of the reaction, reprecipitation was performed using acetone to obtain a white polymer. When the obtained polymer was analyzed by NMR, the target product was well supported. When the molecular weight was measured using GPC, the mass average molecular weight was about 8,000. The obtained polymer was dissolved in distilled water (2% by mass), and the UCST was measured using a visible light transmittance of 500 nm in a quartz cell. When this dissolved aqueous solution was cooled to 30 ° C., it became cloudy, and observation with an optical microscope revealed that a coacervate having a diameter of about 5 μm was formed. When this coacervate is left for about 1 hour, the coacervate layer is separated into a lower layer and an upper aqueous layer, and the obtained polymer is
It was found to be a UCST-CV polymer.

Example 3 Separation of Cibacron Blue (Dye) Using an Aqueous Solution of Poly-N-acryloylbutanoic Acid 1 mg of Cibacron Blue was added to 2 ml of a 3% by mass aqueous solution of UCST-CV polymer obtained in Example 2. In addition, the mixture was heated to 40 ° C. and dissolved. The aqueous solution was cooled to 20 ° C. and left for 1 hour to form a coacervate. When the ratio of the dye contained in the coacervate layer and the upper aqueous layer was measured with an absorptiometer, the ratio of the dye contained in the coacervate layer and the dye contained in the aqueous layer was 96: 4. The dye was separated and collected by dialysis.

Example 4 Synthesis and Properties of a Copolymer of N-Acryloylbutanoic Acid and Acrylamide (30: 1) 3 parts by weight of N-acryloylbutanoic acid and 0.1 part by weight of acrylamide were dissolved in 80 ml of dimethyl sulfoxide. Then, polymerization was carried out for 3 hours under a nitrogen atmosphere using 0.03 parts by mass of AIBN as an initiator. After completion of the reaction, reprecipitation was performed using acetone to obtain a white polymer. When the obtained polymer was analyzed by NMR, the target product was well supported. When the molecular weight was measured using GPC, the mass average molecular weight was about 6000. The obtained polymer was dissolved in distilled water (2% by mass),
The UCST was measured at about 30 ° C. using a visible light transmittance of 500 nm in a quartz cell. This dissolved aqueous solution
When cooled to 20 ° C., it became cloudy and was observed with an optical microscope to reveal that a coacervate having a diameter of about 5 μm had been formed. When this coacervate was allowed to stand for about 1 hour, the coacervate layer was separated into a lower layer portion and an upper aqueous layer, and the obtained polymer was found to be a UCST-CV polymer.

Example 5 Inclusion of Adreamycin in Coacervate Produced from UCST-CV Polymer and Its Release 3 mg of adreamycin was mixed with 5 ml of 2% by mass of the aqueous solution of UCST-CV polymer obtained in Example 4, Dissolved at ° C. Thereafter, the mixture was cooled to 20 ° C. to form a coacervate layer, and the aqueous layer was separated. Adreamycin was not detected in the aqueous layer by high performance liquid chromatography. Distilled water was added to the 2 ml coacervate layer, heated to 40 ° C. again, and analyzed by high performance liquid chromatography. As a result, it was confirmed that adreamycin was quantitatively released. When this solution was cooled again to 20 ° C., a coacervate was formed. It was a coacervate with a diameter of about 5 microns as observed by an optical microscope.

[0052]

Industrial Applicability The UCST-CV polymer of the present invention is effectively applied to separation of various substances, immobilization of enzymes, DDS, etc. in aqueous solutions, for example, in aqueous solutions, physiological saline, buffer solutions and the like. You can do it. In particular, it can be effectively used for calibration and control of substances whose temperature is difficult to set and substances which are not preferable in a high-temperature environment (for example, proteins such as bioproducts, enzymes and antibodies), or chemovalves. In addition, the U of the present invention
The CST-CV polymer can provide an effective separation means by being supported on magnetic particles or other supports.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C12N 11/08 C12N 11/08 C (72) Inventor Hiroko Furukawa 1-1-1, Higashi 1-chome, Tsukuba-shi, Ibaraki Foundation (72) Kazunori Kataoka 7-3-1 Hongo, Bunkyo-ku, Tokyo Faculty of Engineering, Tokyo University (72) Katsuhiko Ueno 1-1-1 Higashi, Tsukuba, Ibaraki Pref. F-term in Engineering Research Institute (Reference) 4B033 NA01 NA22 NB02 NB12 NB36 NB67 NC06 ND04 4C076 AA64 AA95 CC27 EE13H EE48H FF68 GG27 4D056 AB15 AC11 AC20 AC30 BA01 CA14 CA17 CA26 CA39 4J031 AA04 AC02AB01 AB01 AL01Q AL08R AM15Q AM21P AM21R BA16P BA34R BC83R CA03 CA05 JA53

Claims (6)

[Claims] At least one compound represented by the following general formula (1)
A thermo-responsive polymer which is contained as a kind of monomer component, exhibits an upper critical solution temperature characteristic in an aqueous solution, and has a coacervate forming ability. Embedded image (In the formula (1), R ₁ represents a hydrogen atom or a methyl group, R ₂
Represents a single bond or a linear or branched alkylene group having 1 to 5 carbon atoms. ) 2. The thermoresponsive polymer according to claim 1, further comprising a hydrophilic monomer or a hydrophobic monomer as a copolymer component. 3. The thermoresponsive polymer according to claim 1, further comprising a ligand molecule monomer as a copolymerization component. 4. A liquid-liquid phase distribution method comprising a step of bringing an object to be separated and the thermoresponsive polymer according to claim 1 into contact with an aqueous solvent. 5. An immobilized enzyme comprising an enzyme immobilized on the thermoresponsive polymer according to claim 1. 6. A drug release agent comprising the thermoresponsive polymer according to claim 1.