Systems for performing two-dimensional chromatography are disclosed. The system includes a first switching valve fluidly coupled to a first separation column. The system includes a second switching valve coupled to a second separation column. The second switching valve is fluidly coupled to the first switching valve. The system includes an input/output valve in fluid communication with the first switching valve and the second switching valve that is configured to direct one or more mobile phases to the first switching valve. The system includes a sampling valve fluidly coupled to the first switching valve that includes at least one fraction capturing device. Methods of separating compounds using the systems are disclosed. Methods of retrofitting existing two-dimensional chromatography systems are also disclosed.

Systems and methods for generating radionuclides, such as radium-224. Systems herein may include a first cartridge having a first opening, a second opening, and a chamber therebetween having a first resin having affinity for thorium-228 and bismuth-212; a second cartridge having a first opening, a second opening, and a chamber therebetween having a second resin having affinity for thorium-228 and bismuth-212, a third cartridge having a first opening, a second opening, and a chamber therebetween comprising a third resin having affinity for thorium-228 and bismuth-212, a fourth cartridge having a first opening, a second opening, and a chamber therebetween having a third resin having affinity for lead-212; wherein a continuous flow path is formed from a top of the first cartridge though the second cartridge, through the third cartridge, and to a bottom of the fourth cartridge during system use.

There is provided a method of operating a liquid chromatography arrangement, the liquid chromatography arrangement comprising: a solvent pump arranged to flow a liquid solvent over a liquid chromatography column; a restrictor arranged to restrict the liquid solvent from leaving the liquid chromatography column; and a liquid pump arranged to provide liquid flow between the liquid chromatography column and the restrictor, the method comprising: flowing the liquid solvent through the liquid chromatography column using the solvent pump; and controlling a liquid pressure within the liquid chromatography column by providing a liquid flow between the liquid chromatography column and the restrictor using the liquid pump.

A target component is collected using a preparative separation and purification device having a holder for holding a trap column in which the target component has been captured, a liquid feeder for feeding a first solvent having compatibility with the water remaining in the trap column and a second solvent having low compatibility with water and high compatibility with the first solvent into the trap column, a flow-path switch for connecting the exit end of the trap column to a waste liquid flow path and a collection flow path, and a control unit for controlling the flow-path switch so that solution including water flows into the waste liquid flow path.