Apparatus and method for manufacturing radioactive nuclide, and kit for manufacturing radioactive nuclide

Abstract

To provide an apparatus for manufacturing a radioactive nuclide by which it is possible to manufacture a radioactive nuclide in a shorter recovery time and with less recovery liquid volume than conventional ones.SOLUTION: A manufacturing apparatus according to one aspect of the invention is an apparatus for manufacturing a radioactive nuclide, and includes: at least one holding body including a parent nuclide of the radioactive nuclide and an adsorbent that holds the parent nuclide of carrier-free; and a container that sparsely accommodates the holding body.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an apparatus for producing a radionuclide, a method for producing a radionuclide, and a kit for producing a radionuclide.

Background Art

[0002] In the field of nuclear medicine, radionuclides are used for applications such as treatment, diagnosis, and research. Since radionuclides decay over time, when using radionuclides with a short half-life, the nuclides may be prepared on-site in a laboratory or the like.

[0003] As a method for preparing a radionuclide on-site, an eluent is poured into a column filled with a resin adsorbed with a parent nuclide to elute and recover a daughter nuclide, which is the target radionuclide, and the parent nuclide remaining in the column is subsequently used as a source of the radionuclide. Such a method is called milking and is disclosed in, for example, Non-Patent Documents 1 to 3.

Prior Art Documents

[0004]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] ​However, in the prior art as disclosed in Non-Patent Documents 1 to 3, in order to elute a daughter nuclide sufficient for use, the eluent is slowly poured into the column, so that a long time, for example, about several minutes to several tens of minutes, is required for recovery. In addition, the amount of the recovered solution is as large as several mL to several tens of mL, and since the concentration of the daughter nuclide tends to be low, additional treatment such as concentration may be required for use. Further, in the concentration, not only the daughter nuclide but also components such as hydrochloric acid contained in the eluent are concentrated, so that the labeling of the daughter nuclide may be inhibited.

[0006] One aspect of the present invention aims to realize a production apparatus for a radionuclide that can produce a radionuclide with a shorter recovery time and a smaller amount of recovered solution as compared with the prior art.

Means for Solving the Problems

[0007] In order to solve the above problems, a production apparatus according to one aspect of the present invention is a production apparatus for a radionuclide, comprising at least one holder including a parent nuclide of the radionuclide and an adsorbent holding the carrier-free parent nuclide, and a container that loosely houses the holder.

Effects of the Invention

[0008] According to one aspect of the present invention, a radionuclide can be produced with a shorter recovery time and a smaller amount of recovered solution as compared with the prior art.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Embodiment for Carrying out the Invention

[0010] 〔Apparatus for Producing Radionuclide〕 The radionuclide production apparatus 10 according to an embodiment of the present invention will be described with reference to FIG. 1. FIG. 1 is a cross-sectional view schematically showing the radionuclide production apparatus 10 according to an embodiment of the present invention.

[0011] The production apparatus 10 is an apparatus used for producing a radionuclide. In the present embodiment, the radionuclide to be produced is 103m Rh (half-life T 1 / 2 56 minutes). As shown in FIG. 1, the production apparatus 10 includes a holder 11 and a container 12.

[0012] 103m Rh is suitable for medical applications and the like because its decay mode is desirable in treatments using Auger nuclides. On the other hand, because its half-life is short, on-site preparation is essential (see, for example, Bernhardt et al. Acta Oncol. 2001, 40, pp. 602-608, and Filosofov et al. Nucl. Med. Biol. 2021, 94-95, pp. 1-19). However, 103m Regarding Rh, it has been conventionally difficult to prepare a solution with a small liquid volume (i.e., high radioactivity concentration) that can be used for the above applications. However, in the present embodiment, 103m Rh can be produced with a short recovery time and a small amount of recovered liquid.

[0013] (Holder) The holder 11 is a member that holds the parent nuclide, which is the source of the radionuclide, and includes the parent nuclide of the radionuclide and the adsorbent that holds the parent nuclide. In the present embodiment, the holder 11 is particles with a particle diameter of about 600 μm.

[0014] The parent nuclide is a nuclide that is converted into a radionuclide by radioactive decay over time. In the present embodiment, as the parent nuclide103 Pd (half-life T 1 / 2 17 days) is adopted.

[0015] In the present invention, the combination of the radionuclide / nucleophile is 103m Rh / 103 not limited to Pd. The radionuclide is selected according to the desired application from any radionuclide generated by radioactive decay over time. The nucleophile is selected from nucleophiles that can be prepared without a carrier according to the type of the radionuclide. As an example, as the combination of the radionuclide / nucleophile, 68 Ga / 68 Ge, 99 Mo / 99m Tc, 137 Cs / 137m Ba, 44 Ti / 44 Sc, 62 Cu / 62 Zn, 72 Se / 72 As, 82 Sr / 82 Rb, 113 Sn / 113m In, 144 Ce / 144 Pr, 172 Hf / 172 Lu, 188 W / 188 Re, 191 Os / 191m Ir, etc. can be mentioned.

[0016] The adsorbent is a material for holding the nucleophile. In the present embodiment, particles of an anion exchange resin are adopted as the adsorbent.

[0017] In the present invention, the adsorbent is not limited to an anion exchange resin, and a conventionally known material can be adopted as the adsorbent for milling. For example, as the adsorbent, strongly basic anion exchange resins having a trimethylammonium group or a dimethylethanolammonium group as a functional group; strongly acidic ion exchange resins having a sulfonic acid group or a carboxylic acid group as a functional group; chelating resins having a thiol group, a sulfonic acid group, a phosphonic acid group, an aminophosphonic acid group, a picolinylamine group, or a semicarbamic acid group as a functional group; inorganic oxides such as alumina, silica, zeolite, CeO2, SnO2, TiO2, ZrO2, Fe2O3, Sb2O5, WO3, and MoO3; may be mentioned.

[0018] Further, in the present invention, the shape of the adsorbent is not limited to particles. The shape of the adsorbent may be any shape that can be loosely accommodated in the container 12, and may be, for example, rod-shaped, plate-shaped, or mesh-shaped. As the shape of the adsorbent, it is preferable to select a shape with a larger specific surface area.

[0019] In the holding body 11, the adsorbent holds a no-carrier-added (nca) parent nuclide. In this specification, "holding a no-carrier-added parent nuclide" means that among the isotopes present in the element of the parent nuclide, only the isotope that produces a radionuclide (i.e., the parent nuclide, which may also be called "hot") is substantially held, and a stable isotope that does not produce a radionuclide (which may also be called "cold") is not substantially held. In the present embodiment, the holding body 11 holds 103 "hot" 102 Pd among the Pd isotopes, and does not hold 104 "cold" 105 Pd, 106 Pd, 108 Pd, and 110 Pd. Such an isotope of "hot" alone is sometimes called an "nca-parent nuclide". In the present embodiment, the holding body 11 is 103 an nca-parent nuclide generated by utilizing the 103 Rh(p,n) 103It is manufactured by immersing an adsorbent in a solution containing Pd overnight.

[0020] In the present embodiment, the adsorbent holds the parent nuclide at a content such that the radioactivity per 1 g of the carrier 11 is about 500 MBq. In the present embodiment, since the nca-parent nuclide is used as a source of radionuclides, there is no competition for adsorption to the adsorbent between "hot" and "cold" compared to the case of using a parent nuclide including "cold", and more "hot" radionuclides can be adsorbed by the adsorbent. Therefore, in the present embodiment, it is possible to use the carrier 11 having a higher radioactivity than the prior art.

[0021] Although not limiting, in the present invention, the radioactivity per 1 g of the carrier 11 is preferably 500 MBq or more, more preferably 5 GBq or more, and still more preferably 10 GBq or more. There is no particular upper limit for the radioactivity per 1 g of the carrier 11, but it may be, for example, 1 TBq or less.

[0022] Also, in the present invention, the total amount of radioactivity of the carrier 11 accommodated in the container 12 may be appropriately determined according to the desired amount according to the use of the radionuclide. For example, for experimental use with small animals, the total amount may be 50 MBq or more, for administration to humans, the total amount may be 1 GBq or more, and for tracer use, the total amount may be 2 MBq or more.

[0023] (Container) The container 12 is a member for accommodating the carrier 11 and further accommodating an eluent when using the manufacturing apparatus 10. As shown in FIG. 1, the container 12 includes an accommodation part 121, an inlet 122, an outlet 123, and two filters 124 and 125. The accommodation part 121 communicates with the inlet 122 and the outlet 123 with the filters 124 and 125 interposed therebetween, respectively. In the present embodiment, as the container 12, a column having a volume of 100 μL for the accommodation part 121 is adopted.

[0024] In the present invention, the volume of the container 12 is not limited to 100 μL, and for example, it may be 1 mL or less, preferably 500 μL or less.

[0025] The accommodating portion 121 is a space for accommodating the holders 11, and in the present embodiment, ten holders 11 are accommodated. In the present embodiment, the volume of the accommodating portion 121 is sufficiently large with respect to the total volume of the holders 11 accommodated in the container 12. Therefore, the accommodating portion 121 accommodates the holders 11 in a state where the holders 11 are sparsely dispersed and has a hollow space in most of its volume. Therefore, the accommodating portion 121 can further accommodate an eluent in the method for producing a radionuclide using the production apparatus 10. The production method will be described later by changing the reference drawings.

[0026] Although not limiting, the ratio of the total volume of the accommodated holders 11 to the volume of the accommodating portion 121 of the container 12 is preferably 5% by volume or less, more preferably 1% by volume or less. The higher the ratio within this range, the more sparsely the accommodating portion 121 accommodates the holders 11. The lower limit of the ratio of the total volume is not particularly limited, but for example, the ratio of the total volume is 0.01% by volume or more.

[0027] The inlet 122 is an opening for introducing an eluent into the accommodating portion 121, and the outlet 123 is an opening for discharging the eluent from the accommodating portion 121. The filters 124 and 125 are members for preventing the holders 11 from flowing out of the accommodating portion 121 while allowing the eluent to pass through. In the present embodiment, polyethylene filters are employed as the filters 124 and 125.

[0028] In the present embodiment, a column having two openings (the inlet 122 and the outlet 123) is adopted as the container 12, but the present invention is not limited thereto. The container 12 only needs to be provided with at least one opening for introducing and discharging the eluent 13. Therefore, the container 12 may have only one opening, and the opening may also serve as the functions of the inlet 122 and the outlet 123. Further, the container 12 may further include a detachable or openable / closable cap for sealing each opening.

[0029] The container 12 may further include a shielding layer that covers the periphery of the accommodating portion 121 and shields the radiation from the holding body 11. The shielding layer can be made of, for example, lead. The manufacturing apparatus 10 according to the present embodiment is smaller than a conventional manufacturing apparatus for radioactive nuclides called a generator. Therefore, when a shielding layer is provided for the manufacturing apparatus 10, the shielding layer is also miniaturized compared to a conventional shielding layer, and it is possible to easily handle the manufacturing apparatus 10.

[0030] (Auxiliary agent) In the present embodiment, only the holding body 11 is accommodated in the container 12, but the present invention is not limited thereto. In the present invention, the manufacturing apparatus 10 may further include an auxiliary agent accommodated in the container 12. Examples of the auxiliary agent include powders of platinum group metals such as Pt and Ir. By using the powder of the platinum group metal, 103m the Rh yield is improved and the amount of breakthrough (the parent nuclide contained in the recovered solution) is reduced.

[0031] In the present embodiment, the 103m Rh / 103 To avoid adsorption inhibition of Pd, it is preferable to use a powder of a platinum group metal other than Pd and Rh. However, in an embodiment employing another combination as the radioactive nuclide / parent nuclide combination, Pd powder or Rh powder may be used as the platinum group metal powder.

[0032] [Method for manufacturing radioactive nuclide] The manufacturing method M10 of a radionuclide using the manufacturing apparatus 10 will be described with reference to FIG. 2. FIG. 2 is a flowchart showing the flow of the manufacturing method M10 of a radionuclide using the manufacturing apparatus of the radionuclide shown in FIG. 1. As shown in FIG. 2, the manufacturing method M10 includes an elution step S11 and a recovery step S12.

[0033] Each step included in the manufacturing method M10 will be described with reference to FIG. 3. FIG. 3 is a diagram schematically showing the state of the manufacturing method M10 shown in FIG. 2. (a) shows the state of the manufacturing apparatus 10 at the start, (b) shows the state after adding the eluent 13 in the elution step S11, and (c) shows the state of recovering the eluent 13 in the recovery step S12.

[0034] (Elution step) The elution step S11 is an elution step of adding the eluent 13 to the container 12 provided in the manufacturing apparatus 10 and eluting the radionuclide from the adsorbent. As shown in FIG. 3(b), in the elution step S11, the eluent 13 is introduced into the manufacturing apparatus 10 through the inlet 122, and the accommodation portion 121 is filled with the eluent 13. Here, by previously sealing the discharge port 123 with a cap (not shown), the eluent 13 is held in the accommodation portion 121 without leaking from the accommodation portion 121.

[0035] In the present embodiment, the added eluent 13 is maintained in the accommodation portion 121 overnight. As a result, as time passes, the radioactive decay of the parent nuclide progresses, a radionuclide which is a daughter nuclide is generated, and for each of the parent nuclide and the daughter nuclide, an equilibrium state is achieved between the adsorption reaction to the adsorbent and the dissociation reaction to the eluent 13.

[0036] In the present invention, the time for maintaining the eluent 13 in the accommodation portion 121 is not limited to overnight. In the elution step S11, the eluent 13 is preferably maintained for a time of t max or more.

[0037] In this specification, t maxIt refers to the time from adding the eluent 13 to the container 12 until the concentration of the daughter nuclide reaches its maximum, and is calculated by the following formula.

[0038]

Number

[0039] In the formula, k1 represents the decay constant of the parent nuclide, and k2 represents the decay constant of the daughter nuclide. The decay constant k is equal to ln2 / T 1 / 2 and is equal to this. In this embodiment, k1 = 4.72×10 -7 ( / s), k2 = 2.06×10 -4 ( / s), and t max = 8.2 hours.

[0040] In this embodiment, a 0.1M HCl aqueous solution is adopted as the eluent 13. However, the present invention is not limited thereto, and as the eluent, an HCl aqueous solution with an appropriate concentration, pure water, etc. may be adopted.

[0041] (Recovery step) The recovery step S12 is a step of recovering the eluent 13 containing the radionuclide. As shown in FIG. 3(c), in the recovery step S12, by introducing additional eluent 13 into the production apparatus 10 through the inlet 122, the eluent 13 accommodated in the accommodation portion 121 is pushed out, and the eluent 13 discharged from the production apparatus 10 through the outlet 123 is recovered. In this embodiment, the additional eluent 13 is a 0.1M HCl aqueous solution and has the same components as the eluent 13 introduced in the elution step S11.

[0042] In this embodiment, first, 600 μL of air is introduced into the accommodation portion 121, the eluent 13 is pushed out and recovered as the recovered solution. Further, for cleaning the accommodation portion 121, 500 μL of additional eluent 13 and then 10 mL of air are introduced into the accommodation portion 121, whereby 500 μL of the eluent 13 is discharged and further recovered as the recovered solution.

[0043] In this embodiment, the additional eluent 13 and air are introduced over 5 seconds. Here, since the storage part 121 is pre-filled with the eluent 13 in most of its volume and the eluent 13 is discharged simultaneously with the introduction of the eluent 13 and air, the recovery time is the same as the introduction time, i.e., 5 seconds.

[0044] Note that in the present invention, the amount of the eluent to be recovered is not limited to that described above for this embodiment. For example, it may be 1 mL or less, preferably 500 μL or less. Similarly, the recovery time is also not limited to that described above for this embodiment. For example, it may be 5 seconds or less, preferably 2 seconds.

[0045] Also, in the present invention, the additional eluent 13 used in the recovery step S12 may be the same component as the eluent 13 used in the elution step S11, or may be a different component. For example, an HCl aqueous solution may be used in the elution step S11, and pure water may be used in the recovery step S12. Also, in the present invention, it is not necessary to use the additional eluent 13 in the recovery step S12. In this case, the stored eluent 13 may be recovered by removing the cap that seals the discharge port 123 without introducing the additional eluent 13.

[0046] (Repeating step) As shown in FIG. 2, in this embodiment, when the elution step S11 and the recovery step S12 are each performed once, the manufacturing method M10 ends. However, the present invention is not limited to this, and the elution step S11 and the recovery step S12 may be repeatedly performed at least twice each. In this case, after the recovery step S12, the next elution step S11 and the next recovery step S12 may be performed in order. Here, in the next elution step S11, for cleaning, an amount of the eluent 13 exceeding the volume of the storage part 121 may be introduced into the storage part 121, and the overflowed eluent 13 may be discarded.

[0047] [Kit] A kit for producing a radionuclide by implementing the production method M10 also falls within the scope of the present invention. In the present embodiment, the kit includes a production apparatus 10, an eluent 13 enclosed in a container separate from the production apparatus 10, a recovery container for recovering the eluent 13 containing the parent nuclide, and an instruction manual for explaining the production method M10 to the user.

[0048] In the present embodiment, the instruction manual is a paper medium with instructions for the user printed on the paper surface, but the present invention is not limited to this. The instruction manual may be, for example, an electronic medium that stores instructions for the user, or instead of explaining the production method M10, it may be an information medium that explains a method of accessing a medium (such as a URL) that can be viewed on the Internet and that explains the production method M10.

[0049] Note that in the kit according to the present embodiment, the eluent 13 is enclosed in a container separate from the production apparatus 10 for storage and distribution, but the present invention is not limited to this. The eluent 13 may be stored and distributed in a state of being housed in the container 12 of the production apparatus 10.

[0050] 〔Summary〕 As understood from the above description, the present invention includes the following aspects.

[0051] Aspect 1: A production apparatus (10) for a radionuclide, comprising at least one holder (11) containing a parent nuclide of the radionuclide and an adsorbent holding the carrier-free parent nuclide, and a container (12) that loosely houses the holder.

[0052] According to such an embodiment, during the production of a radionuclide, the production apparatus can simultaneously maintain in a container a holding body with reduced volume by holding a carrier-free parent nuclide and an eluent having a larger volume relative to the holding body. Under such conditions, since the holding body is in contact with the eluent for a long time, for each of the parent nuclide and the daughter nuclide (radionuclide), an equilibrium state according to the partition coefficient occurs between a small amount of the holding body and a large amount of the eluent. On the other hand, in a conventional production apparatus, by densely filling an adsorbent in a container, separation according to the difference in partition coefficient is performed in a pseudo multi-stage manner in a flow path. Therefore, compared with the conventional production apparatus, in the production apparatus of this embodiment where only one-stage separation occurs, it has been conventionally considered that a large amount of the parent nuclide is mixed into the recovered liquid and it is unsuitable for the production of radionuclides. However, the inventor has found that even in the production apparatus of this embodiment, the mixing of the parent nuclide remains within an acceptable range for practical use. This may be due to the fact that the parent nuclide and the daughter nuclide form radio colloids in the eluent and behave differently from general substances in the solution. And, in the case of the production apparatus of this embodiment, since it is possible to fill the container with the eluent in an equilibrium state in advance before the recovery step, compared with the conventional case, it is possible to produce radionuclides with a smaller amount of the recovered liquid and a shorter recovery time.

[0053] Aspect 2: The production apparatus according to Aspect 1, wherein the radioactivity per 1 g of the holding body is 5 GBq or more.

[0054] According to such an embodiment, a holding body showing a higher radioactivity compared with the conventional case serves as a supply source of the radionuclide. Therefore, the radionuclide can be produced as a recovered liquid with a high concentration.

[0055] Aspect 3: The production apparatus according to Aspect 1 or 2, wherein the ratio of the total volume of the holding body accommodated in the container to the volume of the container is 5% by volume or less.

[0056] According to such an aspect, in the manufacturing apparatus, the container houses the holder in a more sparsely dispersed state. Therefore, the equilibrium between the holder for the daughter nuclide and the eluent tends to shift more towards the dissociation state, and the radionuclide can be produced as a recovery solution with a high concentration.

[0057] Aspect 4: A manufacturing apparatus according to any one of Aspects 1 to 3, wherein the volume of the container is 1 mL or less.

[0058] According to such an aspect, the volume of the container is smaller compared to the conventional case. Therefore, the amount of the recovery solution can be made smaller. Further, since the volume of the container is small, the amount of the eluent remaining in the container at the time of recovery is reduced, so the yield is improved.

[0059] Aspect 5: The radionuclide is 103m Rh, and the parent nuclide is 103 Pd. A manufacturing apparatus according to any one of Aspects 1 to 4.

[0060] According to such an aspect, 103m Rh can be produced with a short recovery time and a small amount of the recovery solution.

[0061] Aspect 6: A manufacturing method (M10) of a radionuclide, including an elution step (S11) of adding an eluent (13) to the container provided in the manufacturing apparatus according to any one of Aspects 1 to 5 and eluting the radionuclide from the adsorbent, and a recovery step (S12) of recovering the eluent containing the radionuclide.

[0062] According to such an aspect, the radionuclide can be produced with a smaller amount of the recovery solution and a shorter recovery time compared to the conventional case.

[0063] Aspect 7: In the elution step, the eluent added to the container is maintained for a time of t max or more of the radionuclide. The manufacturing method according to Aspect 6.

[0064] According to such an embodiment, in the elution step, an equilibrium state is sufficiently achieved in the eluent. Therefore, a radionuclide can be produced as a high-concentration recovered solution.

[0065] Aspect 8: The production method according to Aspect 6 or 7, wherein in the recovery step, the amount of the eluent to be recovered is 1 mL or less and the recovery time is 5 seconds or less.

[0066] According to such an embodiment, a radionuclide can be produced with a smaller amount of the recovered solution as compared with the conventional case.

[0067] Aspect 9: The production method according to any one of Aspects 6 to 8, wherein the elution step and the recovery step are repeated.

[0068] According to such an embodiment, the radionuclide generated from the parent nuclide remaining in the holder after one recovery step can be repeatedly recovered, and efficient production of the radionuclide can be realized in terms of economy.

[0069] Aspect 10: A kit for producing a radionuclide, comprising the production apparatus according to any one of Aspects 1 to 5 and an eluent.

[0070] According to such an embodiment, a radionuclide can be produced with a smaller amount of the recovered solution and a shorter recovery time as compared with the conventional case.

[0071] 〔Supplementary Notes〕 The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

Examples

[0072] One example of the present invention will be described below. In this example, a production apparatus for a radionuclide according to the prior art and a production apparatus for a radionuclide according to one aspect of the present invention were fabricated, and a production method for a radionuclide was implemented using each production apparatus.

[0073] [Example 1] (Pretreatment of adsorbent) As the adsorbent, particles of strongly basic anion exchange resin DIAION TM SA11AL (manufactured by Mitsubishi Chemical Corporation) were used. After thoroughly rinsing the resin with pure water, it was immersed in 1M HCl aqueous solution overnight. Then, the resin was rinsed with ultrapure water (UPW) until the rinsing solution became neutral after rinsing. The rinsed resin was immersed in 0.1M HCl aqueous solution overnight.

[0074] (Adsorption of nucleophilic species) 103 2 mL of 0.1M HCl aqueous solution containing Pd (i.e., nucleophilic species without carrier) and 10 to 20 particles of the pretreated resin were placed in a 5 mL sampling tube and shaken overnight with a shaker. After placing the resin in a small column (volume 100 μL), 6 mL of 0.1M HCl aqueous solution was passed through the column to wash away the Pd 103 that remained on the resin surface and did not adsorb to the resin. Thus, a production apparatus of Example 1 was obtained in which 2 mg of a retainer with a radioactivity of 5 GBq per gram was accommodated in the small column. In the production apparatus of Example 1, the proportion of the resin particles accommodated in the volume of the small column was about 1% by volume.

[0075] [Example 2] In the production apparatus of Example 1, 5 mg of Pt powder was further added to the small column to obtain a production apparatus of Example 2.

[0076] [Comparative Example 1] (Pretreatment of adsorbent) As the adsorbent, particles of strongly basic anion exchange resin DIAION TM SA11AL (manufactured by Mitsubishi Chemical Corporation) were used. After thoroughly rinsing the resin with pure water, it was immersed in 1M HCl aqueous solution overnight. Then, the resin was rinsed with ultrapure water (UPW) until the rinsing solution became neutral after rinsing.

[0077] (Adsorption of nucleophilic species) The column was packed with 3 mL of the pretreated resin, and then 20 mL of 0.1 M HCl aqueous solution was loaded onto the column at a flow rate of 0.5 mL / min. 103 5 mL of 0.1 M HCl aqueous solution containing Pd was loaded onto the column at a flow rate of 0.2 mL / min. 103 Finally, 10 mL of 0.1 M HCl aqueous solution was loaded onto the column, and the Pd that was not retained by the resin was removed. 103 The Pd was washed away. As a result, 2.8 g of the support having a radioactivity of 3.6 MBq per gram was packed in the column, and the production apparatus of Comparative Example 1 was obtained. In the production apparatus of Comparative Example 1, the proportion of the resin contained in the column was about 70 volume % of the volume of the column.

[0078] [Test Example 1] Radioactive nuclides were produced using the production equipment that was fabricated.

[0079] 100 μL of 0.1 M HCl aqueous solution was loaded as an eluent into the small column of the production apparatus of Example 1 and left to stand overnight. Then, 600 μL of air, 500 μL of 0.1 M HCl aqueous solution, and 10 mL of air were passed through the small column in order for a total of about 2 seconds, and the discharged solution was collected. The amount of the collected solution and the collection time are shown in Table 1.

[0080] Also, 103m The Rh yield was measured in the production equipment before loading the eluent. 103m Rh activity in the collected solution immediately after collection 103m The activity ratio of Rh was calculated using the following formula. 103m The Rh yield is shown in Table 1.

[0081] Y = (I2-I3 / 2) / (I1 / 2) In the formula, Y is 103m I1 represents the Rh yield. I2 represents the peak intensity at 39.7 keV in the gamma-ray spectrum of the small column measured using a germanium semiconductor detector before loading the eluent. Since permanent equilibrium is established between the parent nuclide and the support containing the resin, both nuclides 103 Pd and 103mThe radioactivity of Rh is equal to each other, and the contributions of both nuclides to the peak intensity of the measured gamma-ray spectrum are also equal to each other. Therefore, 50% of the peak intensity at 39.7 keV can be regarded as 103m the activity of Rh. I2 represents the peak intensity at 39.7 keV in the gamma-ray spectrum of the recovered solution measured immediately after recovery. I3 represents the peak intensity at 39.7 keV in the gamma-ray spectrum of this recovered solution measured 2 days after recovery.

[0082] Also, the 103 Pd mixing ratio in the recovered solution was calculated using the following method. Specifically, 100 μL of the recovered solution was mixed with 10 mL of a liquid scintillation cocktail, and signals in the energy region of 35 keV to 100 keV were measured using a liquid scintillation counter. Here, the emission rates of the electron beams belonging to this energy region are almost equal for both nuclides. Therefore, by fitting the decay curve with the following formula and estimating the signal value immediately after recovery, the ratio of 103 Pd mixed into the recovered solution from the radioactivity of both nuclides was calculated. The calculated 103 Pd mixing ratio is shown in Table 1.

[0083] [Number]

[0084] In the formula, A product represents the signal value. λ A and λ B respectively represent 103 the decay constants of Pd and 103m Rh. N A0 and N B0 respectively represent the number of 103 Pd and 103m Rh particles in the recovered solution immediately after recovery.

[0085] In addition, the same tests were conducted using the production apparatuses of Example 2 and Comparative Example 1, respectively, instead of the production apparatus of Example 1. Further, the same tests were conducted using the production apparatus of Example 2 instead of the production apparatus of Example 1 and using UPW instead of the 0.1 M HCl aqueous solution as the eluent.

[0086] The results of each test are shown in Table 1. In Table 1, the 103m Rh recovery rate of Comparative Example 1 is a value considering the decay during the inevitable recovery time of 14 minutes 103m Rh(T 1 / 2 56 minutes). The breakthrough increase rate represents the ratio of the breakthrough of each example to the breakthrough of Comparative Example 1. The concentration increase rate represents the ratio of the concentration of Rh in the recovery solution of each example to the concentration of Rh in the recovery solution of Comparative Example 1. Further, each test was repeated 7 times with the same operation, and the average value and standard deviation of the results are shown in Table 1. The breakthrough increase rate and the concentration increase rate were calculated by the following formulas. 103m The breakthrough increase rate = (CR1 / CR2) × (Y1’ / Y2’) 103m In the above formula, CR1 represents the Pd contamination rate of the analysis target, CR2 represents the Pd contamination rate of Comparative Example 1. Y1’ represents the Rh recovery rate of the analysis target without considering the decay during the recovery time, which is equal to the Rh recovery rate described in Table 1 for Examples 1 and 2. Y2’ represents the Rh recovery rate of Comparative Example 1 without considering the decay during the recovery time, which is 39%.

[0087] The breakthrough increase rate = (CR1 / CR2) × (Y1’ / Y2’) In the above formula, CR1 represents the 103 Pd contamination rate of the analysis target, CR2 represents the 103 Pd contamination rate of Comparative Example 1. Y1’ represents the 103m Rh recovery rate of the analysis target without considering the decay during the recovery time, which is equal to the 103m Rh recovery rate described in Table 1 for Examples 1 and 2. Y2’ represents the 103m Rh recovery rate of Comparative Example 1 without considering the decay during the recovery time, which is 39%.

[0088] The concentration increase rate = (Y1 / Y2) × (V2 / V1) In the above formula, Y1 represents the 103m Rh recovery rate of the analysis target, Y2 represents the 103m Rh recovery rate of Comparative Example 1. V1 represents the volume of the recovery solution of the analysis target, V2 represents the volume of the recovery solution of Comparative Example 1.

[0089]

Table 1

[0090] As shown in Table 1, in Examples 1 and 2, compared with Comparative Example 1, 103m Rh could be produced with a shorter recovery time and a smaller amount of recovered liquid. Also, in Examples 1 and 2, compared with Comparative Example 1, 103 while the Pd mixing rate and breakthrough in the recovered liquid slightly deteriorated, the degree of deterioration (about 0.2% increase in the mixing rate, about 2 - 3 increase rate in breakthrough) was significantly exceeded 103m and the Rh yield and concentration were improved (about 20% increase in the yield, 13 - 17 increase rate in the concentration). From these results, it was found that the production apparatuses of Examples 1 and 2 were sufficiently practical.

[0091] 〔Test Example 2〕 In Test Example 1, the breakthrough per production of a radionuclide was about 0.05% in Comparative Example 1 and about 0.15% in Example 1. Also, the yield of the radionuclide was 33% in Comparative Example 1 and 54% in Example 1. Therefore, under the assumption that the breakthrough and yield were constant, for each number of uses of the production apparatus, the ratio of the parent nuclide remaining in the production apparatus (with the value before use being 100) was simulated, and the amount of the radionuclide obtained from the decreased parent nuclide was simulated. The simulation results are shown in Table 2.

[0092]

Table 2

[0093] As shown in Table 2, in Example 1, although the ratio of the remaining parent nuclide gradually decreased compared with Comparative Example 1, due to the high yield in Example 1, the ratio of the obtained radionuclide was stably at a higher level. From these results, it was found that the production apparatus according to the present invention was also suitable for a method of use for producing radionuclides repeatedly such as milling.

Industrial Applicability

[0094] The present invention can be used for the production of radionuclides for applications such as treatment, diagnosis, research, etc.

Explanation of Signs

[0095] 10 Manufacturing apparatus 11 Holder 12 Container 13 Eluent 121 Accommodation part 122 Inlet 123 Outlet 124, 125 Filters

Claims

1. An apparatus for producing a radionuclide, comprising: at least one holder containing a parent nuclide of the radionuclide and an adsorbent holding the carrier-free parent nuclide; a container that loosely houses the holder. The production apparatus.

2. The radioactivity per gram of the holder is 5 GBq or more. The production apparatus according to Claim 1.

3. The ratio of the total volume of the holders accommodated in the container to the volume of the container is 5% by volume or less. The production apparatus according to Claim 1.

4. The volume of the container is 1 mL or less. The production apparatus according to Claim 1.

5. The radioactive nuclide is １０３ｍ Rh, and the parent nuclide is １０３ Pd. The production apparatus according to Claim 1.

6. A method for producing a radionuclide, comprising: an elution step of adding an eluent to the container provided in the production apparatus according to any one of Claims 1 to 5 to elute the radionuclide from the adsorbent; a recovery step of recovering the eluent containing the radionuclide. The production method.

7. In the elution step, maintain the eluent added to the container for a time of t ｍａｘ or longer. The production method according to Claim 6.

8. In the recovery step, the amount of the eluent recovered is 1 mL or less, and the recovery time is 5 seconds or less. The production method according to Claim 6.

9. The elution step and the recovery step are repeated. The production method according to Claim 6.

10. A kit for producing a radionuclide, comprising: the production apparatus according to any one of Claims 1 to 5 and an eluent. The kit.

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