A method for producing 225.sup.A including: a method (X) for purifying a .sup.226Ra-containing solution, including an adsorption step of allowing a .sup.226Ra ion to adsorb onto a carrier having a function of selectively adsorbing a divalent cation by bringing a .sup.226Ra-containing solution into contact with the carrier under an alkaline condition, and an elution step of eluting the .sup.226Ra ion from the carrier under an acidic condition; a method for producing a .sup.226Ra target, including an electrodeposition liquid preparation step of preparing an electrodeposition liquid by using a purified .sup.226Ra-containing solution obtained by the method (X), and an electrodeposition step of electrodepositing a .sup.226Ra-containing substance on a substrate by using the electrodeposition liquid; and a step of irradiating a .sup.226Ra target produced by the method for producing a .sup.226Ra target with at least one selected from a charged particle, a photon, and a neutron by using an accelerator.

A radioactive fine particle manufacturing system and method to manufacture physically stable radioactive fine particles, and which enables performance evaluation of a radioactivity measuring instrument employing a physical indicator, by controlling radioactivity concentration, and facilitating performance evaluation of the overall radioactivity measuring instrument. The radioactive fine particle manufacturing system includes a radioactive gas generating system, a specific particle-sized aerosol generating system and a mixing chamber, to manufacture radioactive fine particles employing natural radioactive nuclides, and uses. .sup.220Rn to manufacture radioactive fine particles using physically stable progeny nuclides. In the mixing chamber, the progeny nuclides are caused to attach only to an aerosol having a specific particle size, to generate radioactive fine particles having a specific particle size.

A radioactive fine particle manufacturing system and method to manufacture physically stable radioactive fine particles, and which enables performance evaluation of a radioactivity measuring instrument employing a physical indicator, by controlling radioactivity concentration, and facilitating performance evaluation of the overall radioactivity measuring instrument. The radioactive fine particle manufacturing system includes a radioactive gas generating system, a specific particle-sized aerosol generating system and a mixing chamber, to manufacture radioactive fine particles employing natural radioactive nuclides, and uses. .sup.220Rn to manufacture radioactive fine particles using physically stable progeny nuclides. In the mixing chamber, the progeny nuclides are caused to attach only to an aerosol having a specific particle size, to generate radioactive fine particles having a specific particle size.

An object of the present invention is to provide a method for purifying efficiently and easily a .sup.226Ra-containing solution obtained when .sup.225Ac is produced from a .sup.226Ra target, a method for producing a .sup.226Ra target by using the purified .sup.226Ra-containing solution obtained by the above purification method, and a method for producing .sup.225Ac including these above methods. The method for purifying a .sup.226Ra-containing solution according to the present invention is characterized by including an adsorption step (R1) of allowing .sup.226Ra ions to adsorb onto a carrier having a function of selectively adsorbing divalent cations by bringing a .sup.226Ra-containing solution (a) into contact with the carrier under an alkaline condition; and an elution step (R2) of eluting the .sup.226Ra ions from the carrier under an acidic condition.

An object of the present invention is to provide a method for purifying efficiently and easily a .sup.226Ra-containing solution obtained when .sup.225Ac is produced from a .sup.226Ra target, a method for producing a .sup.226Ra target by using the purified .sup.226Ra-containing solution obtained by the above purification method, and a method for producing .sup.225Ac including these above methods. The method for purifying a .sup.226Ra-containing solution according to the present invention is characterized by including an adsorption step (R1) of allowing .sup.226Ra ions to adsorb onto a carrier having a function of selectively adsorbing divalent cations by bringing a .sup.226Ra-containing solution (a) into contact with the carrier under an alkaline condition; and an elution step (R2) of eluting the .sup.226Ra ions from the carrier under an acidic condition.

An isotope production system, emanation generator, and process are disclosed for production of high-purity radioisotopes. In one implementation example, high-purity Pb-212 and/or Bi-212 isotopes are produced suitable for therapeutic applications. In one embodiment the process includes transporting gaseous radon-220 from a radium-224 bearing generator which provides gas-phase separation of the Rn-220 from the Ra-224 in the generator. Subsequent decay of the captured Rn-220 accumulates high-purity Pb-212 and/or Bi-212 isotopes suitable for direct therapeutic applications. Other high-purity product isotopes may also be prepared.

An isotope production system, emanation generator, and process are disclosed for production of high-purity radioisotopes. In one implementation example, high-purity Pb-212 and/or Bi-212 isotopes are produced suitable for therapeutic applications. In one embodiment the process includes transporting gaseous radon-220 from a radium-224 bearing generator which provides gas-phase separation of the Rn-220 from the Ra-224 in the generator. Subsequent decay of the captured Rn-220 accumulates high-purity Pb-212 and/or Bi-212 isotopes suitable for direct therapeutic applications. Other high-purity product isotopes may also be prepared.

A method for producing 225.sup.A including: a method (X) for purifying a .sup.226Ra-containing solution, including an adsorption step of allowing a .sup.226Ra ion to adsorb onto a carrier having a function of selectively adsorbing a divalent cation by bringing a .sup.226Ra-containing solution into contact with the carrier under an alkaline condition, and an elution step of eluting the .sup.226Ra ion from the carrier under an acidic condition; a method for producing a .sup.226Ra target, including an electrodeposition liquid preparation step of preparing an electrodeposition liquid by using a purified .sup.226Ra-containing solution obtained by the method (X), and an electrodeposition step of electrodepositing a .sup.226Ra-containing substance on a substrate by using the electrodeposition liquid; and a step of irradiating a .sup.226Ra target produced by the method for producing a .sup.226Ra target with at least one selected from a charged particle, a photon, and a neutron by using an accelerator.

An isotope production system, emanation generator, and process are disclosed for production of high-purity radioisotopes. In one implementation example, high-purity Pb-212 and/or Bi-212 isotopes are produced suitable for therapeutic applications. In one embodiment the process includes transporting gaseous radon-220 from a radium-224 bearing generator which provides gas-phase separation of the Rn-220 from the Ra-224 in the generator. Subsequent decay of the captured Rn-220 accumulates high-purity Pb-212 and/or Bi-212 isotopes suitable for direct therapeutic applications. Other high-purity product isotopes may also be prepared.

An isotope production system, emanation generator, and process are disclosed for production of high-purity radioisotopes. In one implementation example, high-purity Pb-212 and/or Bi-212 isotopes are produced suitable for therapeutic applications. In one embodiment the process includes transporting gaseous radon-220 from a radium-224 bearing generator which provides gas-phase separation of the Rn-220 from the Ra-224 in the generator. Subsequent decay of the captured Rn-220 accumulates high-purity Pb-212 and/or Bi-212 isotopes suitable for direct therapeutic applications. Other high-purity product isotopes may also be prepared.