A microfluidic cassette for synthesizing a radioactive tracer comprising: - A mounting card, - A microfluidic circuit, at least partly integrated into the mounting card, comprising: ∘ at least one connector for supply by a vial (Pf), configured to connect a vial to the microfluidic circuit, ∘ at least one isotope port, configured for introducing a radioisotope into the microfluidic circuit, ∘ at least one reaction chamber (R1, R2, R3, R4), connected to the at least one connector for supply by a vial and to the at least one isotope port by capillaries, ∘ at least one mixing chamber (M1, M2, M3, M4), positioned upstream of the at least one reaction chamber (R1, R2, R3, R4) and connected to the at least one reaction chamber (R1, R2, R3, R4) upstream of which it is positioned by at least one capillary, ∘ at least one formulation chamber, connected to the at least one isotope port and to the at least one connector for supply by a vial (Pf) and positioned downstream of the at least one reaction chamber (R1, R2, R3, R4), and ∘ at least one connector for connecting a syringe, positioned downstream of the at least one formulation chamber and connected to the at least one formulation chamber by at least one capillary. - A mounting card, - A microfluidic circuit, at least partly integrated into the mounting card, comprising: ∘ at least one connector for supply by a vial (Pf), configured to connect a vial to the microfluidic circuit, ∘ at least one isotope port, configured for introducing a radioisotope into the microfluidic circuit, ∘ at least one reaction chamber (R1, R2, R3, R4), connected to the at least one connector for supply by a vial and to the at least one isotope port by capillaries, ∘ at least one mixing chamber (M1, M2, M3, M4), positioned upstream of the at least one reaction chamber (R1, R2, R3, R4) and connected to the at least one reaction chamber (R1, R2, R3, R4) upstream of which it is positioned by at least one capillary, ∘ at least one formulation chamber, connected to the at least one isotope port and to the at least one connector for supply by a vial (Pf) and positioned downstream of the at least one reaction chamber (R1, R2, R3, R4), and ∘ at least one connector for connecting a syringe, positioned downstream of the at least one formulation chamber and connected to the at least one formulation chamber by at least one capillary. ∘ at least one connector for supply by a vial (Pf), configured to connect a vial to the microfluidic circuit, ∘ at least one isotope port, configured for introducing a radioisotope into the microfluidic circuit, ∘ at least one reaction chamber (R1, R2, R3, R4), connected to the at least one connector for supply by a vial and to the at least one isotope port by capillaries, ∘ at least one mixing chamber (M1, M2, M3, M4), positioned upstream of the at least one reaction chamber (R1, R2, R3, R4) and connected to the at least one reaction chamber (R1, R2, R3, R4) upstream of which it is positioned by at least one capillary, ∘ at least one formulation chamber, connected to the at least one isotope port and to the at least one connector for supply by a vial (Pf) and positioned downstream of the at least one reaction chamber (R1, R2, R3, R4), and ∘ at least one connector for connecting a syringe, positioned downstream of the at least one formulation chamber and connected to the at least one formulation chamber by at least one capillary.