Patent Number: 059321784
Section: summary

REFERENCE TO PATENTS, APPLICATIONS AND PUBLICATIONS PERTINENT TO THE INVENTION As far as we know, there is available the following prior art document pertinent to the present invention: Japanese Patent Provisional Publication No. 6-157,572 laid open as of Jun. 3, 1994 The contents of the prior art disclosed in the above-mentioned prior art document will be discussed later under the heading of "BACKGROUND OF THE INVENTION". BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a synthesizer of fluoro-deoxy glucose (hereinafter referred to as "FDG") used as a labeled compound in a positron emission tomography (hereinafter referred to as "PET") system. RELATED ART STATEMENT As a method for observing and diagnosing the state in a human body by means of an image in the medical field, the image diagnosis based on a PET system using a substance emitting positron is now attracting the general attention. According to the image diagnosis based on the PET system, it is possible to obtain not only a formal image of diseases such as a cancer but also a functional image of the motion of blood or oxygen in a human body, thus displaying a remarkable power in the diagnosis of a brain damage or a cardial malady. The PET system is an image diagnosis system using a radioactive isotope having a short half-value period, and substantially comprises the following steps of: (1) accelerating ions to a high energy in a cyclotron; PA1 (2) producing a radionuclide by irradiating the thus accelerated ions to a material referred to as a target in a target box which is a reactor; PA1 (3) using the thus produced radionuclide as a raw material, and preparing a compound labeled with a radioactive isotope capable of being administered to a human body in a labeled compound synthesizer; and PA1 (4) administering the thus prepared labeled compound to a human body, detecting a distribution of the labeled compound incorporated in the human body by means of a scanner, and converting the result of detection into an image by a computer. As a labeled compound for the PET system, there is known fluoro-deoxy-glucose, i.e., FDG. FDG is a labeled compound in which a part of glucose is substituted with an .sup.18 F! fluoride ion which is a positron emission nuclide (the half-value period thereof being 119.7 minutes), and is used for the diagnosis of a brain function and a malignant tumor. As a method for synthesizing FDG, there is known the method proposed by Hamacher et al. This method of synthesis comprises a step of a labeling reaction for combining an .sup.18 F! fluoride ion which is a radioactive isotope (also referred to as a radionuclide or a positron emission nuclide) with a compound, and a step of a hydrolysis reaction for separating a protecting group (usually, an acetyl group) from a reaction intermediate product obtained from the labeling reaction. A method for synthesizing FDG (hereinafter referred to as the "prior art") is disclosed in Japanese Patent Provisional Publication No. 6-157,572 laid open as of Jun. 3, 1994, which will be described with reference to FIG. 1: Proton particles accelerated in a cyclotron (not shown) are irradiated onto O-18(.sup.18 O) water in a target box 1 to produce an .sup.18 F! fluoride ion. The O-18(.sup.18 O) water containing the thus produced .sup.18 F! fluoride ion (hereinafter referred to as the "target water") is taken out from the target box 1, and, as shown in FIG. 1, sent to a target water container 2. Then, the target water is passed through an anion-exchange resin 3 from the target water container 2 to trap the .sup.18 F! fluoride ion in the target water by means of the anion-exchange resin, and the remaining target water is recovered in a target water recovery container 4. Then, a potassium carbonate aqueous solution is sucked up from a potassium carbide aqueous solution container 5 by means of a syringe 6, and is passed through the anion-exchange resin 3 to extract the .sup.18 F! fluoride ion trapped by means of the anion-exchange resin 3. The thus extracted .sup.18 F! fluoride ion is sent to a reaction vessel 7. Then, an acetonitrile solution of kryptofix 222 is sent from a kryptofix 222 container 8 to the reaction vessel 7. Subsequently, the reaction vessel 7 thus receiving the .sup.18 F! fluoride ion and the acetonitrile solution of kryptofix 222 is heated to evaporation-eliminate moisture in the reaction vessel 7. Then, after the elimination of moisture in the reaction vessel 7, acetonitrile is sucked up from an acetonitrile container 9 by means of a syringe 10, and is sent to the reaction vessel 7. Then, the reaction vessel 7 is heated again to ensure a sufficient evaporation-elimination of moisture in the reaction vessel 7. Then, after the sufficient evaporation-elimination of moisture in the reaction vessel 7, an acetonitrile solution of 1,3,4,6-tetra-O-acetyl-2-O-trifluoromethane-sulfonyl-.beta.-D-mannopyranos e (hereinafter referred to as "triflate"), which is a reaction substrate, is sent from a triflate container 11 to the reaction vessel 7. In the reaction vessel 7, a labeling reaction of triflate is performed at a temperature of about 80.degree. C. for about five minutes. Then, after the completion of the labeling reaction, water is sucked up from a water container 12 by means of a syringe 13, and is sent to the reaction vessel 7. Then, the solution present in the reaction vessel 7 is passed through a SepPak C-18 cartridge 14 from the reaction vessel 7 to cause the cartridge 14 to trap 4-acetyl-FDG which is a reaction intermediate product in the solution. A waste liquid containing non-reacting .sup.18 F! fluoride ion and kryptofix 222 is sent to a waste liquid recovery container 15. Thus, 4-acetyl-FDG is separated from non-reacting .sup.18 F! fluoride ion and kryptofix 222. Then, acetonitrile is sucked up from the acetonitrile container 9 by means of the syringe, and the separated reaction intermediate product, i.e., 4-acetyl-FDG, extracted from the SepPak C-18 cartridge 14, is sent again to the reaction vessel 7. Subsequently, the reaction vessel 7 receiving the above-mentioned acetonitrile and reaction intermediate product is heated to evaporation-eliminate acetonitrile as an organic solvent. Then, a hydrochloric acid aqueous solution is sucked up from a hydrochloric acid aqueous solution container 16 by means of a syringe 17, and added into the reaction vessel 7. Then, the reaction vessel 7 thus added with the hydrochloric acid aqueous solution is heated at a temperature of about 130.degree. C. for 10 to 20 minutes to perform a hydrolysis reaction. Then, after the completion of the hydrolysis reaction, water is sucked up from the water container 12, and is added into the reaction vessel 7. The thus processed solution in the reaction vessel 7 is then passed sequentially through an ion retardation resin column 18 and a refining column 19, and the synthesized FDG is received in an FDG container 20. There is also known a method of obtaining a synthesized FDG through the same process as in the prior art except that tetrabutyl ammonium hydrocarbonate (abbreviated as "TBAHCO.sub.3 ") is used in place of kryptofix 222 in the prior art. In the prior art, a phase transfer catalyst comprising kryptofix 222 or tetrabutyl ammonium hydrocarbonate is added into the reaction vessel during the labeling reaction. The added catalyst therefore remains in the reaction vessel after the completion of the labeling reaction, thus requiring a process for eliminating this phase transfer catalyst. In addition, because of the use of the foregoing phase transfer catalyst, it is necessary to completely eliminate water hindering the labeling reaction through evaporation, and this takes much time. Furthermore, a process using an anion-exchange resin is necessary for recovery of the target water, this poses a problem of a complicated FDG synthesizing process. Since the .sup.18 F! fluoride ion has a half-value period of about two hours, more processes or more complicated processes lead to a longer period of time for the synthesis, thus resulting in a reduced yield of FDG. Under such circumstances, there is an increasing demand for development of an FDG synthesizer, in which a synthesizing process is simplified, with an improved yield of a synthesized product, and the time of synthesis is reduced, but such an FDG synthesizer has not as yet been proposed. SUMMARY OF THE INVENTION An object of the present invention is therefore to provide an FDG synthesizer, in which a synthesizing process is simplified, with an improved yield of a synthesized product, and the time of synthesis is reduced. In accordance with one of the features of the present invention, there is provided an FDG synthesizer, which comprises: a labeling reaction resin column comprising a column filled with a polymer-supported phase-transfer catalyst resin for trapping an .sup.18 F! fluoride ion contained in target water, and performing a labeling reaction between the thus trapped .sup.18 F! fluoride ion and triflate, on the one hand, and a hydrolysis reaction vessel for receiving a reaction intermediate product obtained from said labeling reaction, and performing a hydrolysis reaction by adding a strong acidic aqueous solution or a strong alkaline aqueous solution, on the other hand. In accordance with another one of the features of the present invention, there is provided an FDG synthesizer, wherein: said polymer-supported phase-transfer catalyst resin comprises a phosphonium salt fixed to a polystyrene resin or a pyridinium salt fixed to a polystyrene resin. In accordance with another one of the features of the present invention, there is provided an FDG synthesizer, wherein: said hydrolysis reaction vessel comprises a cation-exchange resin column, and said reaction intermediate product obtained from said labeling reaction is brought into contact with a cation-exchange resin adjusted to an H.sup.+ type in said cation-exchange resin column to perform said hydrolysis reaction. In accordance with another one of the features of the present invention, there is provided an FDG synthesizer, wherein: said hydrolysis reaction vessel comprises a cation-exchange resin column having a heating means and a flow rate control means of said reaction intermediate product containing an organic solvent, and in said cation-exchange resin column, said reaction intermediate product containing said organic solvent obtained from said labeling reaction is heated, to evaporation-eliminate said organic solvent, and at the same time, said reaction intermediate product after the elimination of said organic solvent is brought into contact with a cation-exchange resin adjusted to an H.sup.+ type to perform said hydrolysis reaction, thereby simultaneously performing said elimination of organic solvent and said hydrolysis reaction in said cation-exchange resin column. In accordance with another one of the features of the present invention, there is provided an FDG synthesizer, which comprises: (a) a cartridge-type labeling reaction resin column, (b) a cartridge-type cation-exchange resin column, and (c) a disposable cartridge base into which paths and switchover valves for communicating said labeling reaction resin column and said cation-exchange resin column are incorporated; said cartridge-type labeling reaction resin column comprising a disposable column filled with a polymer-supported phase-transfer catalyst resin, said cartridge-type labeling reaction resin column being one-touch-releasably attachable to said cartridge base, trapping an .sup.18 F! fluoride ion contained in a target water, and performing a labeling reaction between the thus trapped .sup.18 F! fluoride ion and triflate; and said cartridge-type cation-exchange resin column comprising a disposable column filled with a cation-exchange resin adjusted to an H.sup.+ type, said cartridge-type cation-exchange resin column being one-touch-releasably attachable to said cartridge base, and bringing a reaction intermediate product obtained from said the labeling reaction into contact with said cation-exchange resin adjusted to the H.sup.+ type in said cation-exchange resin column to perform a hydrolysis reaction.