The microfluidic device consists of three-inlet channelsone central channel (inlet 1) for the central flow and two side channels (inlets 2 and inlet 3) for the sheath flowsand one outlet where the product is released (Figure and). This inlet configuration facilitates a coaxial integration of the central flow within the sheath flows and a concentric arrangement of the RD zone at the liquid-liquid interface between the central flow and the sheath flow (Figure ). This flow configuration can enable precise control over reagents diffusion along the main microfluidic channel by adjusting the flow rate ratio (FRR = sheath flow rate /central flow rate).