A pervaporation process was implemented into microfluidic chips to purify radiopharmaceuticals for Positron Emission Tomography in continuos-flow. The chip consists of a serpentine microreactor interfaced to a polydimethylsiloxane (PDMS) 10 μm thick membrane. Thanks to different volatility of the components present in the radiopharmaceutical matrix, ethanol (EtOH) is readily removed under gentle heating and nitrogen flow conditions. Three classes of chips with different membrane surface areas (S) and internal volumes (V) have been produced and quantified their pervaporative efficiency at different residence times (Rt) and temperatures. Higher S/V chips (̴ 70 mm−1) apperared the most efficient at a very low residence time (Rt ̴ 10 s) allowing reduction of 67% at 80 °C. Chips of intermediate S/V ratios (̴ 30 mm−1) decreased the EtOH amount up to ̴ 90% at longer residence time (Rt ≥ 26 s). The …