*Article* **A Universal Cassette-Based System for the Dissolution of Solid Targets**

**Gabriele Sciacca 1,2,\* ,† , Petra Martini 3,† , Sara Cisternino 1,2 , Liliana Mou <sup>1</sup> , Jonathan Amico <sup>4</sup> , Juan Esposito <sup>1</sup> , Giancarlo Gorgoni <sup>4</sup> and Emiliano Cazzola <sup>4</sup>**


**Abstract:** Cyclotron-based radionuclides production by using solid targets has become important in the last years due to the growing demand of radiometals, e.g., <sup>68</sup>Ga, <sup>89</sup>Zr, 43/47Sc, and 52/54Mn. This shifted the focus on solid target management, where the first fundamental step of the radiochemical processing is the target dissolution. Currently, this step is generally performed with commercial or home-made modules separated from the following purification/radiolabelling modules. The aim of this work is the realization of a flexible solid target dissolution system to be easily installed on commercial cassette-based synthesis modules. This would offer a complete target processing and radiopharmaceutical synthesis performable in a single module continuously. The presented solid target dissolution system concept relies on an open-bottomed vial positioned upon a target coin. In particular, the idea is to use the movement mechanism of a syringe pump to position the vial up and down on the target, and to exploit the heater/cooler reactor of the module as a target holder. All the steps can be remotely controlled and are incorporated in the cassette manifold together with the purification and radiolabelling steps. The performance of the device was tested by processing three different irradiated targets under different dissolution conditions.

**Keywords:** dissolution system; radiopharmaceutical; solid targets; automation; radiometals production; cyclotron production; radiochemistry; manganese-52; zirconium-89; technetium-99m
