Polyvalent Fluorosurfactant

Abstract

To provide a fluorine-based surfactant that quickly adsorbs to an interface between fluorine oil and water to reduce the interfacial tension of both, thereby stabilizing the droplets.SOLUTION: A fluorine-based surfactant is composed of one compound selected from the group consisting of following formulae (I)-(III): [A]a-X-B-X-D (I), [A]a-X-B-X-[A]b (II), and [A]c-X (III) [where A is a fluorine carbide group, B is oligo(ethylene glycol), D is NH2, NH3, N(CH3) H, N(CH3) H2, N(CH3)2, or N(CH3)3, a, b, and c each independently represent a positive integer, and X is a covalent bond or a linking group, provided that a plurality of Xs included in the compound may be the same or different].SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a fluorosurfactant, a droplet of a W / O emulsion containing the surfactant, and a method for using the same. [Background technology]

[0002] A method of culturing microorganisms inside droplets of water-in-oil emulsions, in which water is dispersed in oil, is considered as a tiny aqueous reaction field and is attracting attention as a high-throughput screening technology. By using a micromixer to mix fluorinated oil with a high dissolved oxygen content with water, it is possible to prepare tens of thousands of homogeneous droplets of several tens of microns per minute, and furthermore to cultivate aerobic microorganisms in each droplet. The volume of a droplet is about one millionth of that of a typical microplate well, which reduces noise due to impurities and improves analysis accuracy.

[0003] Fluorosurfactants are used to stabilize droplets in fluorine oil. Fluorosurfactants have both hydrophilic and fluorine groups in the same molecular skeleton, and when the two liquids of water and fluorine oil are mixed, they orient at the interface between the two liquids to reduce the interfacial tension. Currently, triblock copolymers consisting of perfluoropolyether (PFPE) and polyethylene glycol (PEG) are used as fluorine surfactants to stabilize droplets (Patent Documents 1 and 2). This reduces the interfacial tension by orienting at the interface between water and fluorine oil, and the polymer chains sterically protect the interface to stabilize the droplets. However, although block copolymers synthesized by the linking reaction between two types of polymers are chemically stable, it is difficult to further modify the structure, making it difficult to control the hydrophilic / hydrophobic balance and introduce functional groups.

[0004] Furthermore, in order to expand the molecular structure, Non-Patent Document 1 synthesized a triblock copolymer in which a polyglycerol group, which allows chemical modification of the side chain, was introduced instead of PEG, and Non-Patent Documents 2 and 3 reported polymers in which triol or dendrimer-type polyhydric alcohol was introduced to the end of PFPE.

[0005] When fluorine oil and water are rapidly mixed using a microreactor, it is required that the fluorosurfactant quickly adsorbs to the interface and stabilizes the water droplets (see Non-Patent Document 4). However, the fluorosurfactants currently used have a high molecular weight of 10,000 or more, so rapid adsorption to the interface cannot be expected, and an excessive amount of surfactant is used to compensate for the slow interfacial adsorption speed, which is not economical. In addition, there is a problem that the droplets become unstable when heated, causing the low molecular weight compounds inside to leak out. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2017 / 203280 [Patent Document 2] U.S. Pat. No. 9,498,761 [Non-patent literature]

[0007] [Non-Patent Document 1] Lab on a Chip(2016)Vol.16,p.65-69 [Non-Patent Document 2] ACS Nano(2014)Vol.8,p.3913-3920 [Non-Patent Document 3] Nature Communications (2019) Vol.10, p.4546. [Non-Patent Document 4] Langmuir(2009)Vol.25,p.6088-6093 Summary of the Invention [Problem to be solved by the invention]

[0008] Droplets of W / O emulsions containing fluorinated oils and aqueous liquids are non-toxic to cells, and are expected to be used not only as a culture medium for microorganisms, but also in a wide range of applications, such as enzyme activity testing, DNA / RNA replication / amplification / synthesis, RNA expression, protein synthesis / crystallization, DNA / RNA cleavage / binding / dissociation, synthesis of inorganic materials such as nanoparticles, and specific reaction fields for organic synthesis. However, the limited types of fluorosurfactants that can be used hinder their application. Conventionally used high molecular weight fluorosurfactants have a slow interfacial adsorption rate, so in order to quickly reduce the interfacial tension and stabilize the droplets, it is necessary to dissolve an excess amount in the fluorine oil, and the stability of the resulting droplets is also insufficient. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a fluorosurfactant which has a high interfacial adsorption rate and can be rapidly adsorbed to the interface between a fluorinated oil and water to significantly reduce the interfacial tension between the two, thereby stabilizing droplets. [Means for solving the problem]

[0009] As a result of intensive research aimed at solving the above problems, the inventors have developed a fluorosurfactant whose molecular weight distribution and number of fluorocarbon chains can be freely controlled by a sequential linking reaction of low molecular weight fluorocarbons with polyfunctional oligoethylene glycol, rather than by a linking reaction of high molecular weight PFPE, which has low scalability, with PEG. They have found that this not only actually forms droplets, but also remains stable for a long period of time, thereby completing the present invention.

[0010] The present invention relates to the following fluorosurfactants (1) to (6). (1) [A] a -XBXD (I), [A] a -XBX-[A] b (II), and [A] c -X (III) A fluorosurfactant comprising one compound selected from the group consisting of formulas (I) to (III). In the formula, A is a fluorocarbon group, B is an oligoethylene glycol, D is NH2, NH3, N(CH3)H, N(CH3)H2, N(CH3)2, or N(CH3)3, a, b, and c are each independently a positive integer, and X is a covalent bond or a linking group, and in compounds containing multiple Xs, each may be the same or different. (2) The fluorosurfactant according to the above item (1), wherein the positive integers a, b, and c are each independently 1 to 6, and X is a linking group selected from a chain hydrocarbon group or an aromatic hydrocarbon group which may contain at least one of a carbonyl group (-C=O), an amino group (-NH-), an ether group (-O-), a phenylene group (-CH-), or an aromatic amine (-NCH-). (3) The fluorosurfactant according to the above (1) or (2), wherein the compound of formula (I) is represented by the following formula (A): [ka] Here, R f is a fluorocarbon group having 4 to 12 carbon atoms which may contain an internal linking group containing at least one of a hydrocarbon group (-CH2-), a carbonyl group (-C=O), an amino group (-NH-) or an ether group (-O-), and n is the number of added moles of 1 to 20. (4) The fluorosurfactant according to the above (1) or (2), wherein the compound of formula (II) is represented by the following formula (B): [ka] Here, R f is a fluorocarbon group having 4 to 12 carbon atoms, which may contain a linking group containing at least one of a hydrocarbon group (-CH-), a carbonyl group (-C=O), an amino group (-NH-), or an ether group (-O-), and a plurality of R f may be the same or different, and n is the number of moles added of 1 to 20. (5) The fluorosurfactant according to the above (1) or (2), wherein the compound of formula (III) is represented by the following formula (C): [ka] Here, R f is a fluorocarbon group having 4 to 12 carbon atoms, which may contain a linking group containing at least one of a hydrocarbon group (-CH-), a carbonyl group (-C=O), an amino group (-NH-), or an ether group (-O-), and a plurality of R f may be the same or different. (6) The fluorosurfactant according to the above (1) or (2), wherein the compound of formula (II) is represented by the following formula (D): [ka] Here, R f is a fluorocarbon group having 4 to 12 carbon atoms which may contain a linking group containing a hydrocarbon group (-CH2-), a carbonyl group (-C=O), an amino group (-NH-), or an ether group (-O-), X is a linking group selected from a chain hydrocarbon group or an aromatic hydrocarbon group which may contain at least one of a carbonyl group (-C=O), an amino group (-NH-), an ether group (-O-), a phenylene group (-CH4-), or an aromatic amine (-NC6H4-), f and X may be the same or different, and n is the number of moles added of 1 to 20. The present invention also relates to the following droplets (7) and a method for using the droplets (8). (7) A droplet of a W / O emulsion comprising the fluorosurfactant according to any one of (1) to (6) above, a fluorinated oil, and a hydrophilic liquid. (8) A method for using the droplet described in (7) above as a specific reaction field for culturing microorganisms, enzyme activity testing, DNA / RNA replication / amplification / synthesis, RNA expression, protein synthesis / crystallization, DNA / RNA cleavage / binding / dissociation, synthesis of inorganic materials such as nanoparticles, or organic synthesis. Effect of the Invention

[0011] According to the present invention, the fluorosurfactant can be adsorbed to the fluoro oil / water interface more quickly than conventional polymeric fluorosurfactants, and the amount of fluorosurfactant used for stabilizing droplets can be reduced to about one-third. Furthermore, by controlling the number of fluorocarbons introduced into the polyfunctional oligoethylene glycol, fluorosurfactants with different valencies can be produced, and various physical properties of the fluorosurfactants can be systematically changed. [Brief description of the drawings]

[0012] [Figure 1] 4 shows the interfacial tension reducing ability of fluorosurfactants in the test of Example 5. [Diagram 2] 1 shows the interfacial adsorption rate of a fluorosurfactant in the test of Example 6. [Diagram 3] Photograph of the appearance of the droplets produced in Example 7. [Figure 4] A photograph showing the stability of the droplets prepared in Example 7. [Diagram 5] Photograph of E. coli culture in a droplet of Example 8. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The fluorosurfactant of the present invention is [A] a -XBXD (I), [A] a -XBX-[A] b (II), and [A] c -X (III) The compound is one compound selected from the group consisting of formulas (I) to (III). In formulas (I) to (III), A is a fluorocarbon group, B is an oligoethylene glycol, D is NH2, NH3, N(CH3)H, N(CH3)H2, N(CH3)2, or N(CH3)3, a, b, and c are each independently a positive integer, and X is a covalent bond or a linking group, and in compounds containing multiple Xs, they may be the same or different.

[0014] The positive integers a, b and c relate to the number of fluorocarbon groups A in one molecule, and each independently is preferably 1 to 6. The fluorocarbon group A to be introduced is preferably a monovalent to 12-valent polyvalent fluorine-based surfactant, more preferably a monovalent to 6-valent polyvalent. When X is a linking group, X is a linking group selected from a chain hydrocarbon group or an aromatic hydrocarbon group, which may contain at least one of a carbonyl group (-C=O), an amino group (-NH-), an ether group (-O-), a phenylene group (-CH-), or an aromatic amine (-NCH-). The number of carbon atoms in the chain hydrocarbon group or the aromatic hydrocarbon group is preferably 1 to 40, and more preferably 1 to 20. The molecular weight of the fluorosurfactant is preferably 10,000 or less, and more preferably 8,000 or less.

[0015] The fluorosurfactant according to one embodiment of the present invention is derived from a fluorocarbon having a carboxyl group or an amino group and a polyfunctional oligoethylene glycol, and has a chemical structure in which the two are linked together via an amide bond, etc. An example of such a fluorosurfactant is a fluorosurfactant represented by the following formula (A). In the fluorosurfactant represented by formula (A), one fluorocarbon chain is linked to one oligoethylene glycol via an amide bond or the like. f R is a fluorocarbon group having 4 to 12 carbon atoms, which may contain a linking group containing at least one of a hydrocarbon group (-CH2-), a carbonyl group (-C=O), an amino group (-NH-), or an ether group (-O-), and n is the number of moles added, which is 1 to 20. fWhen contains a hydrocarbon group (-CH2-), the hydrocarbon preferably has 1 to 10 carbon atoms.

[0016] [ka]

[0017] Further, a fluorosurfactant according to another embodiment of the present invention has a chemical structure in which two fluorocarbon chains are linked to one oligoethylene glycol via an amide bond, etc. An example of such a fluorosurfactant is a fluorosurfactant represented by the following formula (B). Here, R f R is a fluorocarbon group having 4 to 12 carbon atoms, which may contain a linking group containing at least one of a hydrocarbon group (-CH2-), a carbonyl group (-C=O), an amino group (-NH-), or an ether group (-O-), and n is the number of moles added, which is 1 to 20. f When contains a hydrocarbon group (-CH2-), the hydrocarbon preferably has 1 to 10 carbon atoms.

[0018] [ka]

[0019] Another embodiment of the fluorosurfactant of the present invention has a chemical structure in which three fluorocarbon groups are linked to one benzene ring via amide bonds, etc. An example of such a fluorosurfactant is a fluorosurfactant represented by the following formula (C). Here, R f R is a fluorocarbon group having 4 to 12 carbon atoms, which may contain a linking group containing at least one of a hydrocarbon group (-CH2-), a carbonyl group (-C=O), an amino group (-NH-), or an ether group (-O-), and n is the number of moles added, which is 1 to 20. f When contains a hydrocarbon group (-CH2-), the hydrocarbon preferably has 1 to 10 carbon atoms.

[0020] [ka]

[0021] Furthermore, a fluorosurfactant according to another embodiment of the present invention has a chemical structure in which four fluorocarbon chains are linked to one hydrophilic group via amide bonds, etc. An example of such a fluorosurfactant is a fluorosurfactant represented by the following formula (D). Here, R f is a fluorocarbon group having 4 to 12 carbon atoms which may contain a linking group containing a hydrocarbon group (-CH2-), a carbonyl group (-C=O), an amino group (-NH-), or an ether group (-O-), X is a linking group selected from a chain hydrocarbon group or an aromatic hydrocarbon group which may contain at least one of a carbonyl group (-C=O), an amino group (-NH-), an ether group (-O-), a phenylene group (-CH4-), or an aromatic amine (-NC6H4-), f and X may be the same or different, and n is the number of moles added of 1 to 20. The chain hydrocarbon group or aromatic hydrocarbon group of the linking group preferably has 1 to 40 carbon atoms, and more preferably has 1 to 20 carbon atoms.

[0022] [ka]

[0023] A specific example of the fluorosurfactant represented by formula (A) is L1 in the following formula 5. [ka]

[0024] A specific example of the fluorosurfactant represented by formula (B) is L2 in the following formula 6. [ka]

[0025] A specific example of the fluorosurfactant represented by formula (D) is L4 in the following formula 7. [ka]

[0026] Using the fluorosurfactant of the present invention, droplets of a W / O emulsion containing a fluoro oil and a hydrophilic liquid can be produced. The droplets of the present invention have a diameter of several tens of μm, and are obtained by mixing either a fluoro oil containing the fluorosurfactant of the present invention or a hydrophilic liquid containing the fluorosurfactant of the present invention with a hydrophilic liquid or a fluoro oil, respectively, using a micromixer, and are stable for at least one week. The diameter of the droplets of the present invention is preferably 1 to 500 μm.

[0027] Examples of the fluorine oil of the present invention include, but are not limited to, NOVEC7500, FC-40, FC-77, and a mixture of one or more of these. Mineral oils can also be used as oils other than fluorine oils. The structure of the micromixer is not particularly limited, but a micromixer having a flow path of several hundred microns or less, preferably several tens of microns can be used. The hydrophilic liquid may be a pure substance or a mixture.

[0028] The droplets of the present invention may contain other components as necessary. Such other components may be water-soluble or amphiphilic, such as lower alcohols, inorganic salts, organic salts, acids, bases, and surfactants. Furthermore, when the droplets of the present invention are used as a chemical reaction field, they may contain catalysts, enzymes, various metal reagents, and the like necessary for the chemical reaction.

[0029] The droplets of the present invention can be used in microbial culture, enzyme activity testing, DNA / RNA replication / amplification / synthesis, RNA expression, protein synthesis / crystallization, DNA / RNA cleavage / binding / dissociation, synthesis of inorganic materials such as nanoparticles, and specific reaction fields for organic synthesis. EXAMPLES

[0030] The present invention will be described in more detail below with reference to examples, but the examples can be modified as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited to the specific examples shown below.

[0031] Example 1: Synthesis of L1 295 mg (0.60 mmol) of 2H,2H,3H,3H-heptadecafluoroundecanoic acid, 76 mg (0.60 mmol), and 30 mg (0.24 mmol) of DMAP were dissolved in 18 mL of tetrahydrofuran and stirred at room temperature for 20 minutes. This mixture was added dropwise to 133 mg (0.60 mmol) of diethylene glycol bis(3-aminopropyl) ether using a dropping funnel over 30 minutes while stirring, and stirred at room temperature for 18 hours. After removing the solvent, the crude product was washed with diethyl ether. It was then purified by silica gel column chromatography (chloroform:methanol=1:1) to obtain L1 in a yield of 159 mg (38%). 1 H-NMR (400MHz, CDCl3, room temperature.) δ(ppm):5.30(s,1H,NH), 3.65-3.56(m,12H,CH2),3.51-3.45(q,4H,CH2,J=8.0 Hz),2.82(p,2H, NH2,J=6.0 Hz),2.45(m,4H,CH2),1.79-1.72 (m, 2H, CH2) 19 F-NMR (377MHz, CDCl3, room temperature) δ (ppm): 126.1,123.5,121.9,121.7,121.6,114.6,80.7 IR(ATR):3600-3100,1645,1552cm -1 MALDI-TOF MS:m / z=694.9(Calcd. 695.2)

[0032] Example 2: Synthesis of L2 483 mg (0.98 mmol) of 2H,2H,3H,3H-heptadecafluoroundecanoic acid, 187 mg (0.97 mmol) of EDC, and 38 mg (0.31 mmol) of DMAP were dissolved in 8 mL of dimethylformamide and stirred at room temperature for 1 hour. 91 mg (0.41 mmol) of diethylene glycol bis(3-aminopropyl) ether was added thereto and stirred at room temperature for 24 hours. After removing the solvent, 30 mL of ethyl acetate / hexane mixed solvent (=9 / 1) was added and washed three times with saturated aqueous sodium chloride solution (30 mL). After drying the organic phase with magnesium sulfate, the solvent was removed and purified by silica gel column chromatography (chloroform:methanol=19:1) to obtain L2 in a yield of 430 mg (90%). 1 H-NMR (400MHz, CDCl3, room temperature) δ(ppm):6.46(s,2H,NH),3.66-3.56(m,2H,CH2),3.41-3.36(q,4H,CH2,J=6.7 Hz),2.45(m,8H,CH2),1.81-1.75(m,4H,CH2) 19 F-NMR (377MHz, CDCl3, room temperature) δ (ppm): 126.1, 123.5, 122.7, 121.9, 121.7, 114.7, 80.8 IR(ATR):1639,1551cm -1 MALDI-TOF MS:m / z =1169.6(Calcd.1169.2)

[0033] Example 3: Synthesis of L4 250 mg (0.89 mmol) of 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetrasodium salt, 1.6 mL (8.9 mmol) of 1H,1H-undecafluorohexylamine, 690 mg (0.79 mmol) of EDC, and 11 mg (0.1 mmol) of DMAP were dissolved in 5 mL of dimethylformamide and stirred at 60°C for 3 days. 30 mL of ethyl acetate was added, and the mixture was washed with dilute hydrochloric acid (10 mL) and water (20 mL), and the organic phase was dried over magnesium sulfate. After removing the solvent, L4 was obtained in a yield of 379 mg (27%) by purifying it by silica gel column chromatography (dichloromethane:methanol = 19:1). 1 H-NMR (400MHz, CDCl3, room temperature) δ (ppm): 7.10 (4H, ArH) 6.93 (4H, ArH), 4.33 (s, 4H), 3.75 (s, 8H, CH2), 2.88 (s, 4H, CH2) 19 F-NMR(377MHz, CDCl3, room temperature) δ(ppm):-80.96,-118.5,-123.0,-123.8,-126.5 MALDI-TOF MS:m / z =1600.9(Calcd.1601.2)

[0034] Example 4: Comparison of solubility The solubilities of the synthesized L1, L2, and L4 in various oils were compared, and the results are shown in Table 1. [Table 1] As shown in Table 1, L1, L2, and L4, which have different valences, show different solubilities in fluorinated oils, and it was found that the types of solvents that can be used can be expanded.

[0035] Example 5: Evaluation of surface activity In a vial, L1 was dissolved in NOVEC 7500 to various concentrations. Fluorine oil of each concentration was dissolved, and the interfacial tension reducing ability of L1 with respect to water / NOVEC 7500 was measured using an interfacial tension measuring device (manufactured by Kyowa Interface Science Co., Ltd., product name "Drop Master DM500") using the hanging drop method. As shown in Figure 1, L1 (▲ in Figure 1) reduced the interfacial tension between water and NOVEC 7500. In addition, the critical micelle concentration (CMC) was determined from the concentration at which the surface tension became a constant value in the graph in Figure 1. The interfacial tension of L2 was measured in the same manner. The results are shown in Figure 1. As shown in Figure 1, L2 (● in Figure 1) exhibited the same interfacial tension reducing ability as L1, although its solubility in NOVEC7500 decreased and it precipitated. The critical micelle concentrations of L1 and L2 and the surface tensions at these concentrations (γ CMC ) are shown in Table 2. For comparison, the measurement results using a conventional product (■ in Figure 1) are also shown in the table.

[0036] [Table 2] As shown in Table 2, it was found that the CMC of L1 and L2 were equivalent. Although the CMC was one order of magnitude higher than that of the conventional product, its interfacial tension reducing ability was comparable to that of the conventional product, demonstrating excellent interfacial activity.

[0037] (Example 6: Comparison of interfacial adsorption rates) L1 and L2 were dissolved in NOVEC7500 to a concentration of 5 mg / ml (approximately 0.5 wt%), and the results of measuring the pendant drop adsorption rate are shown in Figure 2. For comparison, the results of measurements using a conventional product (0.5 wt%) are also shown in the figure. As a result, the interfacial tension value remained constant, with L1 decreasing from 4.3mN / m to 3.0mN / m in about 3 minutes, L2 decreasing from 4.6mN / m to 3.0mN / m in about 4 minutes, and the conventional product decreasing from 8.2mN / m to 3.3mN / m in about 9 minutes. In other words, it became clear that the low molecular weight L1 and L2 adsorbed to the interface more quickly than the conventional product, and the interfacial adsorption rate increased by 2 to 3 times.

[0038] (Example 7: Preparation of droplets using a micromixer) Pure water was placed in the water reservoir of the microchip, and Novec 7500 with various surfactants dispersed in the oil reservoir was placed in the droplet generator (On-chip Biotechnology Co., Ltd.). The valve was then opened, and droplets were created by flowing the sample and oil at 20 kPa. Figure 3 shows a photograph of the appearance of droplets created by a micromixer using Novec 7500 solutions of L1 and L2, which were adjusted to concentrations below and above the CMC (0.2 mg / ml and 5 mg / ml). As a result, it was found that at concentrations below the CMC (0.2 mg / ml), droplets coalesced to form large droplets immediately after generation for all surfactants, whereas at concentrations above the CMC (5 mg / ml), uniform microdroplets were formed, at least immediately after generation, for all surfactants. Coalescence proceeded gradually after generation for L2, whereas for L1, droplets increased and aggregation occurred, but they remained stable without coalescence.

[0039] The time-dependent change in the shape of droplets prepared using an L1 / Novec 7500 solution (5 mg / ml) was observed by phase contrast observation using an optical microscope. The results are shown in Figure 4. It was found that the droplets remained stable for at least three days. In other words, it was revealed that stable droplets could be prepared using L1, even though it is a low-molecular-weight fluorosurfactant.

[0040] Example 8: Cultivation of Microorganisms in Droplets E. coli (E. coli K12 strain) was used for the microbial culture in the droplets. 600E. coli that had been subjected to the above-mentioned purification (pH 7.0, pH 7.0, and pH 7.0) was diluted 1 / 3 and used. The E. coli sample solution prepared as described above was placed in the water reservoir of the microchip, and L1 / Novec 7500 solution (5 mg / ml) was placed in the oil reservoir, and the microchip was set in the droplet production device On-chip Droplet Generator (On-chip Biotechnology, Inc.). The valve was then opened, and droplets containing E. coli were produced by flowing at a sample pressure of 25 kPa and oil pressure of 27 kPa.

[0041] The appearance of the droplets containing E. coli produced using the micromixer is shown in Figure 5 (immediately after encapsulation). At this time, an average of 6.7 ± 2.0 E. coli cells were encapsulated in each droplet (see the enlarged photograph on the right of Figure 5 (immediately after encapsulation), E. coli cells look like spots). The droplets containing E. coli produced were collected in 1.5 mL microtubes and cultured at 37°C for one day. The appearance of the droplets containing E. coli after one day is also shown in Figure 5 (one day later). The number of E. coli inside the droplets after one day was about 20.2 ± 10.5 on average (see the enlarged photograph on the right of Figure 5 (one day later)), and compared to the number of bacteria immediately after encapsulation, it was confirmed that they were proliferating. As described above, it was confirmed that it is possible to culture microorganisms inside the droplets prepared with L1. [Industrial Applicability]

[0042] The fluorosurfactant of the present invention has a high adsorption rate to interfaces and exhibits excellent surface activity. In particular, since droplets can be produced using a micromixer, it is expected to be used in the cultivation of microorganisms, enzyme activity testing, DNA / RNA replication / amplification / synthesis, RNA expression, protein synthesis / crystallization, DNA / RNA cleavage / binding / dissociation, synthesis of inorganic materials such as nanoparticles, and specific reaction fields for organic synthesis.

Claims

1. [A] ａ -X-B-X-D (I) A fluorosurfactant comprising a compound represented by formula (I): In the formula (I), A is a fluorocarbon group, B is an oligoethylene glycol, and D is NH ２ , N.H. ３ , N(CH ３ )H,N(CH ３ ) H ２ , N(CH ３ ) ２ , or N(CH ３ ) ３ a is a positive integer, X is a covalent bond or a linking group, and a plurality of Xs may be the same or different, and the compound of formula (I) is represented by the following formula (A): 【Chemistry 1】 Here, R f is a carbon fluorine group having 4 to 12 carbon atoms which may contain an internal linking group containing at least one of a hydrocarbon group (—CH 2 —), a carbonyl group (—C═O), an amino group (—NH—), or an ether group (—O—), and n is the number of moles added of 1 to 20.

2. The positive integer a is 1 to 6, and X is a carbonyl group (-C=O), an amino group (-NH-), an ether group (-O-), a phenylene group (-C ６ H ４ -), or aromatic amine (-NC ６ H ４ 2. The fluorosurfactant according to claim 1, wherein the linking group is selected from a chain hydrocarbon group or an aromatic hydrocarbon group, and may contain at least one of the following groups therein:

3. A droplet of a W / O emulsion comprising the fluorosurfactant according to claim 1 or 2, a fluorinated oil, and a hydrophilic liquid.

4. A method for using the droplet described in claim 3 as a specific reaction field for microbial cultivation, enzyme activity testing, DNA / RNA replication / amplification / synthesis, RNA expression, protein synthesis / crystallization, DNA / RNA cleavage / binding / dissociation, synthesis of inorganic materials such as nanoparticles, or organic synthesis.

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