JP5313032B2 - Sintered adsorbent and cartridge for solid phase extraction - Google Patents

Description

The present invention relates to an adsorbent for solid phase extraction used in a pretreatment step of chemical analysis and a cartridge for solid phase extraction using the same.

A solvent extraction method (liquid-liquid extraction method) has been used for a long time to extract a measurement object from a liquid sample. Since the solvent extraction method has been pointed out various problems such as the use of a large amount of an organic solvent that is complicated in operation and has a high environmental load, the solvent extraction method has recently been shifted to the solid phase extraction method. The solid-phase extraction method is a physical extraction method based on the interaction between the solid phase and the liquid phase, and the high-affinity of the measurement target substance to the solid-phase extraction agent is used to convert the measurement target substance into the solid-phase extraction agent. Extracted and concentrated on the surface. Compared with the solvent extraction method, it has features such as high recovery rate, high accuracy, rapidity, simplicity, safety, low cost, solvent reduction, easy automation, and field sampling. For this reason, it is widely used for extraction and concentration of trace harmful substances such as agricultural chemicals in environmental samples and food samples that require rapid processing of a large number of specimens.

As a solid phase extractant, a silica-based solid phase extractant in which a hydrophobic group such as an octadecyl group or an octyl group has been introduced on the surface of a silica gel by a silane coupling reaction has been used. Polymer-based solid-phase extraction agents using high-molecular substances are rapidly spreading due to high chemical properties, small lot-to-lot variations, and various types. As a polymer-based solid phase extraction agent, a styrene-divinylbenzene copolymer was initially used. However, in order to improve extraction efficiency, methacrylate and divinylbenzene copolymer (see Patent Document 1), vinylpyrrolidone and divinylbenzene were used. A solid phase extraction agent having a polar group inside such as a copolymer (see Patent Document 2) has been proposed. In addition, multifunctional solid-phase extraction agents such as those in which an ion exchange group is introduced into a hydrophobic solid-phase extraction agent (see Patent Document 3) and those in which a chelating functional group is introduced (see Patent Document 4) have been proposed. .

These solid-phase extraction agents are pulverized or spherical powders of several tens of μm, and are used by filling a reservoir made of resin (mainly made of polypropylene). To create a solid phase extraction reservoir, dry fill the reservoir with a polyethylene sintered filter (called a frit) in the bottom, and then insert the frit onto the packed bed to extract the solid phase. A cartridge is used. A typical solid phase extraction cartridge is shown in FIG. The packed state of the solid phase extraction agent packed by dry packing is not packed as densely as the packed column used in high performance liquid chromatography. Therefore, even if it seems to be uniformly packed immediately after filling, the solid phase extraction agent may move when subjected to vibration or impact, and a gap may be formed between the upper frit and the upper portion of the packed bed. If such a gap is used, there is a problem that the extraction recovery rate fluctuates and the sample solution remains in the cartridge because uniform extraction cannot be performed or rapid elution cannot be performed.

When the solid phase extraction agent is a polymer-based solid phase extraction agent, problems due to swelling and shrinkage also occur. When extracting from a water sample using a solid phase extraction cartridge, the solid phase extractant is first washed with an organic solvent and the packed bed is adjusted. Thereafter, an operation of flowing pure water or the like to match the liquidity of the sample solution is performed (this operation is called conditioning). In general, a polymer-based solid phase extractant swells in an organic solvent, but when a solid phase extractant swollen with an organic solvent is put into water, it contracts at once. That is, since the packed bed swells during conditioning and then contracts, the gaps and channeling as described above may occur. If it is used in such a state, the extraction recovery rate will be reduced and will vary. In order to solve these problems, a polymer-based solid phase extraction agent having a stable shape and free from swelling / shrinking is required.

Patent Documents 5 to 6 propose techniques that can solve the above problems. In these patent documents, a solid phase extractant in powder form is mixed with polymer fibers (pulp) and used as a solid phase extract in the form of a sheet or film by a solvent distillation method or a heat fusion method. It is disclosed. These are obtained by holding a solid-phase extractant of fine particles in a mesh-like sheet or film formed of fibers such as polytetrafluoroethylene, polyolefin, polyaramid, polyamide, polyurethane, and cellulose. The fiber serving as the holding carrier is not dissolved or swollen by the solvent used in the normal solid phase extraction process. Therefore, by using such a method, a solid-phase extract without swelling / shrinking can be produced, and upper and lower frits are not required. However, the solid-phase extract produced by such a method is a thin film having a thickness of 1 mm or less, and is packed in a cylindrical shape like a general solid-phase extraction cartridge, and is necessary by adjusting the height of the packed bed. In order to obtain a sufficient filling amount, complicated work is required. Since these thin-film solid-phase extracts are used in the same manner as ordinary filter paper, it is not possible to use an instrument common to the solid-phase extraction cartridge, so a dedicated instrument must be prepared. Furthermore, since the hole diameter is small, there is a problem that extraction processing at a high flow rate is difficult and clogging is likely to occur.

In recent years, a method for producing a monolithic filler, which is said to provide high separation at a high flow rate, has been proposed (see, for example, Patent Document 9) and has been commercialized. Various studies have also been made on polymer-based monoliths, and Patent Document 10 shows an application example in the solid-phase extraction field. According to the method for producing a polymer monolith of Patent Document 10, it is said that it is possible to produce a columnar solid-phase extraction agent having a through pore of about 0.5 to 10 μm and a mesopore of 2 to 50 nm. Although the through-pore diameter of this polymer monolith is smaller than a void filled with a general particulate solid phase extraction agent, it is presumed that it can be sufficiently used as a solid phase extraction agent. A polymer monolith is produced by a polymerization reaction in which a monomer, a crosslinking agent, a diluent, and a polymerization initiator are placed in a sealed reaction vessel, and a porous body having the same shape as that inside the reaction vessel is obtained. It is done. When used as a column for high-performance liquid chromatography or a solid-phase extraction cartridge, the produced polymer monolith is usually removed from the reaction vessel and further processed and inserted into the target column or cartridge for use. is there. However, since this is complicated, the target column or cartridge itself is used as a reaction vessel, and a monolithic solid-phase extraction agent bed is directly generated inside them. This manufacturing method has the advantage that the step of filling particles can be omitted, and at the same time, since the polymer monolith itself is a porous body, the upper and lower frits used in a normal solid phase extraction cartridge are also unnecessary. However, the method of directly producing a solid-phase extraction agent bed individually by polymerization reaction for each solid-phase extraction cartridge is cumbersome and not suitable for mass production, and the solid-phase extraction made of resin due to the increase in internal pressure due to the polymerization reaction The cartridge may be deformed. Furthermore, when it is desired to introduce various functional groups into the solid-phase extraction agent by chemical reaction to achieve higher functionality, the reaction does not proceed uniformly due to the small through-pores, and the functional group to the solid-phase extraction agent The problem that the introduction rate of is low.

Japanese Patent No. 3274898 Patent Publication 2000-514704 Patent Publication 2002-517574 Japanese Patent Publication No. 2005-213477 Japanese Patent No. 3785438 JP 10-500058 Gazette JP-T-2001-502762 Special Table 2002-524243 JP 2007-292751 A JP 2006-15333 A JP 2008-221611 A

The present invention has been made in view of the above problems, and for solid phase extraction that is easy to handle and can meet various requirements without impairing the function of the particulate porous polymer-based solid phase extraction agent. It is an object of the present invention to provide a solid phase extraction cartridge that does not vary in adsorbent and packing density.

As a result of earnest research, the present invention has mixed a particulate porous polymer solid phase extractant with a thermoplastic resin powder to form a mixture, and this mixture is heated and sintered to obtain a porous sintered body. (Hereinafter sometimes referred to as a porous sintered body), the porous sintered body is easy to handle and meets various requirements without impairing the function of the porous polymer-based solid phase extractant. This is based on the finding of an easy-to-adsorb material for solid phase extraction. That is, when the mixture is heated and sintered, the thermoplastic resin powder in the mixture is fused near the surface layer and bonded to each other to form a porous, three-dimensional network structure. High-quality polymer-based solid-phase extractant becomes a sintered body fixed in this network structure, so it can be handled easily and meets various requirements without impairing the function of the porous polymer-based solid-phase extractant It is possible to produce an adsorbent for solid phase extraction that is easy to perform. At this time, it is expected that the surface of the powder of the polymer-based solid phase extractant and the surface of the thermoplastic resin powder are bonded together by fusion.
That is, a porous polymer-based solid phase extractant in a thermoplastic resin sintered matrix obtained by heating and sintering a mixture of a particulate porous polymer-based solid phase extractant and a thermoplastic resin powder By using a sintered solid-phase extraction adsorbent characterized by being dispersed and fixed, and a solid-phase extraction cartridge having the sintered solid-phase extraction adsorbent mounted on a reservoir or holder The above-mentioned problem is to be solved.

In the present invention, a porous polymer-based solid phase extractant having a degree of swelling of 1.0 to 2.0 determined by the following formula 1 from the bed volume when dried and the bed volume when swollen in a solvent is thermoplastic. Mixed with resin powder.

Formula 1

In the present invention, the mixing ratio of the porous polymer-based solid phase extractant mixed with the thermoplastic resin powder is 10 to 70% by weight.

The thermoplastic resin used in the present invention is mainly composed of polyethylene, polypropylene or a mixture thereof, and if necessary, an ethylene-vinyl acetate copolymer or an ethylene-vinyl alcohol copolymer. Mixtures can also be used.

In the present invention, a solid-phase extraction cartridge is prepared by mounting a sintered solid-phase extraction adsorbent having a porous polymer-based solid-phase extraction agent fixed inside a thermoplastic resin porous sintered body to a reservoir or holder. .

According to the present invention, a porous sintered polymer solid phase extractant and a thermoplastic resin powder are mixed, and a porous sintered body produced by using a fusion method is used as an adsorbent for solid phase extraction. It becomes an adsorbent for solid-phase extraction that is easy to handle and can meet various requirements without impairing the function of the porous polymer-based solid-phase extractant. By attaching this porous sintered body to an appropriate reservoir or holder, Thus, a solid phase extraction cartridge free from fluctuations in packing density due to vibration, swelling and shrinkage can be obtained simply and inexpensively.

FIG. 1 shows a configuration example of a general solid phase extraction cartridge. FIG. 2 shows a configuration example of a solid phase extraction cartridge using a sintered solid phase extraction adsorbent. FIG. 3 shows a configuration example of a cartridge for solid phase extraction using a multilayer sintered solid phase extraction adsorbent in which a porous sintered body layer having different pore diameters is integrally formed on the upper and lower sides. FIG. 4 shows a configuration example of a Luer type solid phase extraction cartridge using a sintered type solid phase extraction adsorbent. FIG. 5 shows a configuration example of a flat plate type solid phase extraction cartridge using a sintered solid phase extraction adsorbent. FIG. 6 shows a diagram showing the operation steps of the solid phase extraction method. FIG. 7 shows a configuration example of a suction manifold used in the solid phase extraction method. FIG. 8 is a graph showing comparison of metal adsorption characteristics at each pH between the adsorbent A for solid phase extraction of Example 1 and the chelate resin particles a. FIG. 8a shows a comparison of adsorption characteristics of pentavalent arsenic As (V) at each pH. FIG. 8b shows a comparison of adsorption characteristics of cadmium Cd at each pH. FIG. 8c shows a comparison of adsorption characteristics of cobalt Co at each pH. FIG. 8d shows a comparison of adsorption characteristics of trivalent chromium Cr (III) at each pH. FIG. 8e shows a comparison of the adsorption characteristics of copper Cu at each pH. FIG. 8f shows a comparison of adsorption characteristics of iron Fe at each pH. FIG. 8g shows a comparison of adsorption characteristics of manganese Mn at each pH. FIG. 8h shows a comparison of adsorption characteristics of molybdenum Mo at each pH. FIG. 8 i shows a comparison of the adsorption characteristics of nickel Ni at each pH. FIG. 8 j shows a comparison of the adsorption characteristics of lead Pb at each pH. FIG. 8k shows a comparison of adsorption characteristics of vanadium V at each pH. FIG. 8l shows a comparison of adsorption characteristics of zinc Zn at each pH.

In the present invention, after mixing the particulate porous polymer-based solid phase extractant and the thermoplastic resin powder, the mixture is heated and sintered by a known method, and cooled to form a porous sintered body. This sintered body is used as an adsorbent for solid phase extraction, and this porous sintered body is attached to an appropriate reservoir or holder to form a solid phase extraction cartridge.

The material of the porous polymer-based solid phase extractant used in the present invention is not particularly limited. Existing hydrophobic resins, hydrophilic resins, ion exchange resins, chelate resins, and the like can be used. Further, the shape thereof is not particularly limited, and may be irregular particles obtained by pulverization of a resin obtained by a known bulk polymerization method, or spherical particles obtained by a known suspension polymerization method.

In general, a polymer-based adsorbent has a characteristic of swelling in a good solvent. Hydrophobic polymer-based solid phase extractants are highly swollen in organic solvents, and ion exchange resins and chelate resins are highly swollen in water. On the basis of the dry volume, the swelling volume in a good solvent may be several times or more. Swelling increases the pore size of the adsorbent and at the same time increases the specific surface area. However, the specific surface area in the non-swelled state is very small, tens of m ² / g or less, so the functions of the particles are fully demonstrated. Can not do it. Although the porous sintered body also has pores, the specific surface area is low, so mixing such particles with a small specific surface area with the thermoplastic resin powder does not provide sufficient function as a porous sintered body. . At this time, if the particles held inside the porous sintered body can swell, the specific surface area will be greatly increased, but the periphery of the particles is sufficiently fixed by fusion with the thermoplastic resin. Cannot swell. Even if a part swells and widens the pores, the pores formed by the porous sintered body are blocked. Furthermore, if the swelling / shrinking is repeated, the fused state with the thermoplastic resin may be lost, and detachment / leakage may occur from the porous sintered body. In order to solve these problems, it is necessary to use particles having a small degree of swelling and a large specific surface area.

In the present invention, the porous polymer-based solid phase extractant mixed with the thermoplastic resin has a low degree of swelling in order to stably fix it in the porous sintered body and to ensure the liquid permeation characteristics during use. Is used. The degree of swelling of the porous polymer-based solid phase extractant can be obtained from the above formula 1 from the bed volume when dried and the bed volume when swollen in a solvent. In the present invention, a polymer carrier having a degree of swelling of 1.0 to 2.0, preferably 1.0 to 1.8 is used. The pore size and specific surface area of the porous polymer-based solid phase extractant are not particularly limited because they depend on the properties of the components to be adsorbed and the coexisting components. Those having a pore diameter of 4 to 50 nm and a specific surface area of 100 to 1000 m ² / g are used.

In the present invention, the amount of the porous polymer solid-phase extractant mixed with the thermoplastic resin powder is 10 to 70% by weight, preferably 10 to 60% by weight. When the addition amount is less than 10% by weight, the amount of the porous polymer-based solid phase extractant fixed in the porous sintered body is small, and the extraction function cannot be sufficiently exhibited. Moreover, when the addition amount of a porous polymer type solid-phase extraction agent exceeds 70 weight%, the moldability of a porous sintered body will fall or physical properties, such as intensity | strength and a softness | flexibility, will fall.

The adsorbent for sintering type solid phase extraction of the present invention is heated and sintered after mixing the porous polymer solid phase extractant and the thermoplastic resin powder. Thermal denaturation becomes a problem. In general, polymer-based solid-phase extraction agents have low heat resistance, and thus polyethylene or polypropylene having a relatively low melting point is used as a thermoplastic resin material in order to prevent this thermal denaturation. These thermoplastic resin powders can be used alone or in combination. These materials have strong water repellency, but in order to improve wettability and further improve flexibility, powders of ethylene-vinyl acetate copolymer and ethylene-vinyl alcohol copolymer are mixed. can do.

The particle diameters of the porous polymer solid phase extractant and the thermoplastic resin powder used in the present invention are not particularly limited, and any particle diameter can be used. The average particle diameter of the phase extractant is 5 to 300 μm, and the average particle diameter of the thermoplastic resin powder is 20 to 800 μm. When the average particle size of the porous polymer-based solid phase extractant is small, leakage from the porous sintered body may occur. In such a case, it is possible to prevent dropping of the porous polymer-based solid phase extractant by increasing the melting degree of the thermoplastic resin, but the porosity of the obtained porous sintered body is reduced, It becomes a porous sintered body with poor permeability. Therefore, usually, a thermoplastic resin powder having an average diameter of 0.5 to 4 times the average diameter of the porous polymer solid phase extractant to be mixed is used. On the other hand, if the particle size of the porous polymer-based solid phase extractant is too large, the degree of fusion with the thermoplastic resin powder will be low, resulting in a porous sintered body with insufficient strength and flexibility. . The shape of the thermoplastic resin powder may be an irregular crush type or a spherical shape.

The adsorbent for sintered solid phase extraction of the present invention is produced by applying a known method for producing a porous sintered body of plastic. That is, 1) a step of preparing a porous polymer-based solid phase extractant having a reactive functional group having a desired function, and 2) particles of the porous polymer-based solid phase extractant and thermoplastic resin powder 3) Step of filling the cavity of the mold with a mixture of the porous polymer-based solid phase extractant and the thermoplastic resin powder while vibrating 4) Filling the mixture of the particles and the powder Placing the molded mold in a constant temperature furnace set to a temperature near the melting point of the thermoplastic resin and heating the mold for a predetermined time, and 5) molding the porous sintered body by cooling the mold It is manufactured by the step of taking out the sintered body.

The pore diameter of the porous sintered body in the adsorbent for sintered solid phase extraction of the present invention is determined by the average particle diameter and particle size distribution of the thermoplastic resin powder used. In order to adjust the filtration accuracy and liquid passing accuracy of the porous sintered body, a multilayer sintered body as shown in Patent Document 11 can be used. In other words, the lower part of the mold is filled with a thermoplastic resin powder having a particle size that can achieve the target filtration accuracy in an amount to obtain the target thickness, and the porous sintered body is formed by heat fusion in a constant temperature furnace. After molding, a method is used in which the mold is once opened, filled with a certain amount of the mixture of particles and powder of the present invention, and heated again in a constant temperature furnace for a predetermined time to form a porous sintered body. By this method, a porous sintered body having a porous sintered body layer having different pore diameters on the lower surface (or upper surface) can be obtained.

The adsorbent for sintered solid phase extraction of the present invention is used as a cartridge for solid phase extraction by being mounted on a reservoir or holder having an appropriate shape and capacity. FIG. 2 shows an example when the adsorbent 12 for solid-phase extraction of the present invention is inserted into a syringe-type reservoir 1. At this time, if the permeability and filtration accuracy of the adsorbent for sintering type solid phase extraction of the present invention become a problem, as shown in FIG. 1, the same as the solid phase extraction cartridge filled with the particulate solid phase extraction agent 11 is used. Frits (2 and 3) may be inserted at the top or bottom, or both, to provide adequate permeability or filtration accuracy. Further, as shown in FIG. 3, a sintered solid phase extraction adsorbent 13 in which porous sintered body layers 13a and 13b are integrally formed on the upper part, the lower part, or both can also be used. In addition, as shown in FIG. 4, a luer type solid phase extraction cartridge in which an adsorbent 14 for sintered solid phase extraction is inserted into a reservoir 4b that uses a cap 4a having a female luer part instead of an open shape at the top. As shown in FIG. 5, a flat plate type solid phase extraction cartridge or the like having a flat plate type holder 5 having a filter holder-like structure and a sintered solid phase extraction adsorbent 15 formed in a flat plate shape. Is also easy.

In the present invention, the material of the reservoir or holder for solid phase extraction is not particularly limited, and stainless steel, glass, or plastic can be used as necessary. Usually, since it is used as a disposable cartridge, an inexpensive plastic such as polypropylene is used.

The solid phase extraction cartridge of the present invention can be used in the same manner as an ordinary solid phase extraction cartridge. That is, as shown in FIG. 6, 1) conditioning is performed using an appropriate solvent / solution, and activation (hydration, solvation) of the solid-phase extraction agent is performed. Pass the sample at a flow rate to extract and concentrate the substance to be measured in the sample solution. 3) Wash out unnecessary components extracted in the solid-phase extractant using an appropriate solvent and solution. 4) Use an appropriate eluent. The measurement target component extracted and concentrated in the solid phase extraction agent is eluted, and 5) the solution containing the eluted measurement target component is measured with an appropriate instrument. Conditioning liquid, sample solution, washing liquid, eluent, etc. can be sent manually to the cartridge for solid phase extraction using a syringe or the like. It is also possible to use a liquid pump or a solid phase extraction manifold 21 as shown in FIG.

In FIG. 7, the solid phase extraction cartridge 6 is set in the solid phase extraction manifold 21. An eluate receiver (for example, a test tube or a beaker) 23 is set in the solid phase extraction manifold 21. Next, suction is started by an aspirator or the like, the inside of the manifold 21 is depressurized, and the specific depressurization is held. Next, conditioning is performed by passing 10 mL each of the solid phase extraction cartridge 6 in the order of, for example, acetonitrile, water, 3M nitric acid, water, and 0.1M ammonium acetate buffer (pH 5). At this time, liquid is passed by opening and closing the cock 22. Thereafter, the sample solution is introduced into the cartridge for solid phase extraction 6 and allowed to flow therethrough, and the target component is adsorbed on the adsorbent for sintering type solid phase extraction of the cartridge for solid phase extraction 6. When the sample has passed through the solid-phase extraction cartridge 6, an appropriate solvent is passed through to wash out unnecessary components adsorbed in the sintered solid-phase extraction adsorbent, and this washing solution removes the solid-phase extraction cartridge 6. After the removal, the cock is closed and the solid phase extraction cartridge 6 is moved to the adjacent cock and attached. Further, in order to elute the adsorbed components, an appropriate solvent is passed through the solid phase extraction cartridge 6 by opening and closing the cock. The eluted component is guided to the eluate receiver 23. Thereafter, the receiver 23 is taken out and further necessary operations such as analysis are performed.
Next, the present invention will be described with reference to examples, but the present invention is not limited to the examples.

Production of Adsorbent A for Sintered Solid Phase Extraction (1) Synthesis of Chelate Resin Particles a The synthesis of the porous polymer carrier was carried out by suspension polymerization. A mixture of 80 g of glycidyl methacrylate, 120 g of ethylene dimethacrylate, 200 g of butyl acetate and 2 g of 2,2′-azobisisobutyronitrile is added to 2,000 mL of a 0.1% aqueous polyvinyl alcohol solution, resulting in an oil droplet diameter of 60 μm. Was stirred as such. Thereafter, a polymerization reaction was carried out at 70 ° C. for 6 hours. The produced copolymer particles were collected by filtration and washed with water and methanol in this order. After air drying for one day, classification was performed to obtain 80 g of a 32-90 μm porous polymer carrier. 70 g of the obtained porous polymer carrier is added to a solution obtained by dissolving 80 g of pentaethylenehexamine in 200 mL of isopropyl alcohol and 800 mL of water, and reacted at 50 ° C. for 6 hours to perform polyamination to obtain a polyaminated resin. The polyaminated resin was collected by filtration and washed with water, methanol and water in this order. The whole amount of the washed polyaminated resin was placed in a solution of 150 g of sodium chloroacetate in 1,000 mL of 1M NaOH and reacted at 40 ° C. for 6 hours to carry out carboxymethylation. The reaction product was filtered and sufficiently washed with water, then replaced with methanol, and dried to obtain chelate resin particles a.

(2) Characteristic evaluation of chelate resin particle a Specific surface area and average pore diameter (measured by Beckman Coulter SA3100 Surface Area Analyzer) of the chelate resin particle a obtained in the above (1) were 180 m ² / g and 12.1 nm, respectively. Met. Moreover, the swelling degree calculated | required from the bed volume of the dry state and the methanol swelling bed volume was 1.18, and it was confirmed that the swelling degree is low. 250 mg of this chelate resin particle a is taken, filled into a syringe barrel reservoir made of polypropylene having an inner diameter of 8.9 mm and a height of 64 mm with a filter having a pore diameter of 20 μm inserted in the lower part, and the same filter is also inserted in the upper part of the filling bed. A cartridge for solid phase extraction was prepared. The solid phase extraction cartridge was conditioned by passing 10 mL each in the order of acetonitrile, water, 3M nitric acid, water and 0.1M ammonium acetate buffer (pH 5). Then, 3 mL of 0.5 M copper sulfate solution adjusted with 0.05 M ammonium acetate buffer (pH 5) was passed through to saturate the chelating functional group with copper, and then washed with 10 mL of water and 5 mL of 0.005 M nitric acid. did. The adsorbed copper was eluted with 3 mL of 3M nitric acid, the volume of the eluate was adjusted to 10 mL, and the absorbance of copper at 805 nm was measured with an absorptiometer to determine the amount of adsorbed copper. As a result, the adsorption amount of copper was 0.44 mmol Cu / g, indicating a sufficient metal adsorption ability. Further, when the flow rate of pure water under a reduced pressure of −30 kPa was measured using this chelate resin particle a-filled solid phase extraction cartridge, it was 44 mL / min.

(3) Production of Adsorbent A for Sintering Solid Phase Extraction 25 g of the chelate resin particles a obtained in the above (1) and 25 g of polyethylene powder (average particle diameter 125 μm) were mixed to obtain a mixture. A part of this mixture was filled while vibrating in a mold cavity from which a cylindrical molded body having a diameter of 9 mm and a height of 10 mm was obtained. Thereafter, the mold was covered and heated in a constant temperature oven at 130 ° C. for 20 minutes. After the heating, the mold was air-cooled, the molded product was taken out, and a cylindrical sintered adsorbent A for solid phase extraction was obtained. Since the average weight of the cylindrical adsorbent A for solid phase extraction is 0.22 g / piece and the mixing amount of the chelate resin particles a is 50%, 0.11 g of the chelate resin particles a is included. Will be.

(4) Characteristic evaluation of adsorbent A for sintering type solid phase extraction The adsorbing material A for sintering type solid phase extraction obtained in (3) above is an injection cylinder made of polypropylene having an inner diameter of 8.9 mm and a height of 64 mm. A solid phase extraction cartridge was prepared by inserting into a mold reservoir, and the amount of copper adsorbed was examined by the same method as in (2) above. The amount of copper adsorption was 0.21 mmol Cu / g, indicating a sufficient metal adsorption capacity. Since the mixing amount of the chelate resin particles a in the adsorbent A for solid-phase extraction is 50%, it means that 95.5% of the adsorption capacity of the chelate resin particles a is maintained. There was no significant functional degradation due to fusion with the metal, and sufficient metal adsorption capacity was exhibited. Moreover, when the flow rate of pure water under a reduced pressure of −30 kPa was measured using this adsorbent A-inserted solid phase extraction cartridge for sintered solid phase extraction, it was 39 mL / min. Although the liquid passing speed was slightly lower than that of the obtained chelate resin particle a-filled solid phase extraction cartridge, it was in a sufficiently usable range. The effluent at the time of this evaluation test was measured using a Beckman Coulter Multisizer 3 Coulter Counter, but no leakage of chelate resin particles was observed. Furthermore, the flow of 60 mL of water-60 mL of methanol was repeated 5 times, but no volume change was observed.

Evaluation test 1

Adsorption characteristic evaluation of adsorbent A for sintered solid phase extraction Solid phase extraction cartridge filled with chelate resin particles a obtained in (2) above, and sintered solid phase extraction obtained in (4) above Metal adsorption characteristics at various pH values were examined using a solid-phase extraction cartridge in which the adsorbent A was inserted. According to the above (2), after conditioning each cartridge for solid phase extraction, a mixed metal standard solution (pentavalent arsenic As (pentavalent), cadmium Cd, cobalt Co, trivalent chromium Cr) adjusted to various pHs. (III), copper Cu, iron Fe, manganese Mn, molybdenum Mo, nickel Ni, lead Pb, vanadium V, zinc Zn, each 0.1 mg / L) were passed through to adsorb the metal. The adsorbed metal was eluted with 3 mL of 3M nitric acid, and the metal concentration in the eluate was measured to determine the recovery rate. A PerkinElmer Optima 3000 DV ICP emission spectroscopic analyzer was used for the measurement of the metal concentration. The result is shown in FIG. The adsorption characteristics of the adsorbent A for sintering type solid phase extraction are almost the same as those of the mixed chelate resin particles a, and the adsorbing material for sintering type solid phase extraction according to the present invention is fixed in the porous sintered body. It was found that the adsorption characteristics of the functional resin particles made were not changed.

Preparation of adsorbent B for sintered solid phase extraction (1) Synthesis of chelate resin particles b A porous polymer carrier was synthesized under the same conditions as in (1) except that 60 g of glycidyl methacrylate and 140 g of ethylene dimethacrylate were used. And classified into 45 to 90 μm. Using this porous polymer carrier, chelate resin particles b were synthesized under the same conditions as in Example 1 (1). The resulting chelate resin particles b had a specific surface area of 232 m ² / g, an average pore diameter of 11.6 nm, and a degree of swelling of 1.17. Moreover, when the copper adsorption amount was calculated | required by the method similar to said (2), it was 0.33 mmol Cu / g.

(2) Production and evaluation of adsorbent B for sintered solid phase extraction 10 g of chelate resin particles b obtained in (1) above, 20 g of polyethylene powder (average particle size 125 μm), and ethylene-vinyl acetate copolymer After mixing 20 g of powder (average particle size 120 μm), it was molded by the same method as in Example 1 (3) to obtain a cylindrical sintered adsorbent B for solid phase extraction having a diameter of 9 mm and a height of 10 mm. . The amount of metal adsorption of this adsorbent B for solid phase extraction was measured according to (4) above. The amount of copper adsorbed was 0.05 mmol Cu / g. Since the mixing amount of the chelate resin particles b in the adsorbent B for sintering type solid phase extraction is 20%, 75.8% of the adsorption capacity of the chelate resin particles a was maintained. It was found that the adsorbent B for sintered solid phase extraction mixed with the ethylene-vinyl acetate copolymer powder rapidly penetrates water even in a dry state and has an effect of improving wettability.

Preparation of adsorbent C for sintered solid phase extraction (1) Synthesis of hydrophobic solid phase extractant c into which anion exchange groups have been introduced 30 g of glycidyl methacrylate, 170 g of divinylbenzene, 180 g of toluene, 20 g of n-dodecane and 2,2 A mixture of 2 g of '-azobisisobutyronitrile was added to 2,000 mL of a 0.1% aqueous polyvinyl alcohol solution, and the mixture was stirred so that the oil droplet diameter was 40 μm. Thereafter, a polymerization reaction was carried out at 80 ° C. for 6 hours. The produced copolymer particles were collected by filtration and washed with water and methanol in this order. After air drying for one day, classification was performed to obtain 75 g of a porous polymer carrier having a size of 32 to 63 μm. 70 g of the obtained porous polymer carrier was added to a solution of 70 g of N, N-dimethylethylamine dissolved in 200 mL of isopropyl alcohol and 800 mL of water, and reacted at 40 ° C. for 6 hours to introduce a quaternary ammonium group. The obtained resin was collected by filtration, washed with water and methanol in this order, and dried to obtain a hydrophobic solid phase extractant c.

(2) Characteristic Evaluation of Hydrophobic Solid-Phase Extracting Agent c Introduced with Anion Exchange Group The specific surface area and average pore diameter of the chelate resin particles a obtained in Example 1 (1) are 645 m ² / g and 5 respectively. .2 nm. Moreover, the swelling degree calculated | required from the bed volume of the dry state and the methanol swelling bed volume was 1.71. It was 0.34 meq / g when the ion exchange capacity | capacitance of the hydrophobic solid-phase extraction agent c which introduce | transduced this anion exchange group was measured by the back titration method. Further, using a solid phase extraction cartridge in which 60 mg of the hydrophobic solid phase extraction agent c introduced with the anion exchange group was filled in the same syringe barrel reservoir as in Example 1 (2), the pressure was reduced to −30 kPa. The flow rate of pure water was measured at 38 mL / min.

(3) Production and evaluation of adsorbent C for sintering type solid-phase extraction 25 g of hydrophobic solid-phase extraction agent c introduced with the anion exchange group obtained in (2) above and polyethylene powder (average particle size 125 μm) ) After mixing 25 g, filling the cavity of the mold to obtain a cylindrical molded body having a diameter of 9 mm and a height of 5 mm while vibrating, under the same conditions as in Example 1 (3), a cylindrical sintered mold Adsorbent C for solid phase extraction was obtained. Since the average weight of this columnar sintered solid-phase extraction adsorbent C is 0.12 g / piece, and the mixing amount of the hydrophobic solid-phase extraction agent c into which an anion exchange group is introduced is 50%, This means that 0.06 g of a hydrophobic solid phase extraction agent c into which an anion exchange group has been introduced is contained. It was 0.15 meq / g when the ion exchange capacity of this adsorbent C for solid phase extraction was measured by a back titration method. Since the mixed amount of the hydrophobic solid phase extraction agent c introduced with the anion exchange group in the adsorbent C for sintering type solid phase extraction is 50%, the hydrophobic solid phase extraction agent introduced with the anion exchange group is 50%. 88.2% of the ion exchange capacity of c was maintained. This adsorbent C for solid phase extraction is inserted into the same syringe cylinder reservoir as in Example 1 (4) to produce a solid phase extraction cartridge, and pure water is passed under a reduced pressure of −30 kPa. The liquid passing speed at this time was 32 mL / min, which was in a sufficiently usable range. In addition, no leakage of particles was observed in the effluent. Furthermore, no volume change was observed even when the water-methanol flow was repeated.

Evaluation test 2

Adsorption characteristic evaluation of adsorbent B for sintering type solid phase extraction Solid phase extraction cartridge filled with 60 mg of hydrophobic solid phase extraction agent c introduced with anion exchange group prepared in (3) above, and Example 2 ( Using the solid-phase extraction cartridge inserted with the cylindrical sintered solid-phase extraction adsorbent C having a diameter of 9 mm and a height of 5 mm prepared in 1), the solid phase extraction of the drug was performed and the recovery rates were compared. It was. A sample prepared by dissolving the drug shown in Table 1 in 10 mL of 1 mol / L sodium acetate buffer was used.

The solid phase extraction cartridge was conditioned by passing 2 mL of methanol, 2 mL of pure water, and 1 mL of 2 mol / L sodium acetate buffer, and the whole sample solution was injected. Subsequently, 2 mL of a mixed solution of 95: 5 = 0.1 mol / L sodium acetate buffer: methanol was passed through the cartridge for washing. Thereafter, 2 mL of methanol was passed through to elute the drug adsorbed on the solid phase extractant. The acidic substance was eluted by passing 4 mL of 2% formic acid-methanol solution. Each drug concentration in the eluate was measured under the conditions shown in Table 2 using HPLC, and the adsorption recovery rate was determined. Table 3 shows the recovery rate of each drug.

From the results in Table 3, the columnar sintered solid-phase extraction adsorbent C can adsorb and recover almost 100% of neutral compounds, basic compounds and acidic compounds. It was found that the characteristics of the introduced hydrophobic solid phase extractant c can be sufficiently exhibited.

According to the present invention, a porous polymer such as a hydrophobic resin, a hydrophilic resin, a chelate resin, or an ion exchange resin can be obtained by a simple method of thermal fusion between a porous polymer-based solid phase extractant and a thermoplastic resin powder. It is possible to obtain a solid-phase extraction cartridge equipped with a high-performance adsorbent for sintered solid-phase extraction, which retains the system solid-phase extraction agent at a high level and does not cause problems such as fluctuations in packing density. The adsorbent for sintered solid-phase extraction of the present invention has a variety of shapes such as a flat plate shape, a disk shape, a columnar shape, a prism shape, a hollow cylindrical shape, a rectangular tube shape, and a cup shape in which one end is closed. In addition to extraction / concentration of components to be measured in liquid samples, it can be used as a cartridge for collecting atmospheric components, etc., before being used for chemical analysis. It can be widely used as a treating agent.

1: syringe type reservoir 2: upper frit 3: lower frit 4: lure type reservoir, 4a: cap, 4b: body 5: flat plate holder, 5a: cap, 5b: body 6: cartridge for solid phase extraction 11: particles Solid-phase extraction agent 12: Sintered solid-phase extraction adsorbent 13 of the present invention: Sintered solid-phase extraction adsorbent 13a of the present invention in which a porous sintered body layer is integrally formed at the upper and lower portions: Upper porous Sintered body layer, 13b: Lower porous sintered body layer 14: Adsorbent for sintered solid phase extraction 15 of the present invention 15: Adsorbent for sintered solid phase extraction of the present invention formed into a flat plate shape 21: Solid phase Extraction suction manifold 22: Stop cock 23: Eluate receiver ●: Metal adsorption recovery rate of sintered solid phase extraction adsorbent A of Example 1 Δ: Metal of chelate resin particles a of Example 1 Adsorption recovery rate

Claims (5)

Particulate porous polymeric solid phase extraction agent and the thermoplastic resin powder multi porous polymeric solid phase extraction agent in the sintered matrix of the thermoplastic resin obtained by heating and sintering a mixture of A sintered solid-phase extraction adsorbent characterized by being dispersed and fixed. The degree of swelling determined by the following formula 1 from the bed volume when the porous polymer-based solid phase extractant mixed with the thermoplastic resin powder is swelled with a solvent is 1.0 to 2 The adsorbent for sintering type solid phase extraction according to claim 1, which is 0.0.
  The sintered solid phase according to claim 1 or 2, wherein a mixing ratio of the porous polymer solid phase extractant mixed with the thermoplastic resin powder is 10 to 70 wt%. Adsorbent for extraction.   The adsorbent for sintered solid phase extraction according to claim 1, wherein the thermoplastic resin is mainly composed of polyethylene, polypropylene, or a mixture thereof. 5. A solid phase extraction cartridge comprising a reservoir or a holder mounted with a sintered solid phase extraction adsorbent in which a porous polymer solid phase extraction agent is fixed in the thermoplastic resin porous sintered body according to claim 1. .