Easy-to-perform and cost-effective fabrication of continuous-flow reactors and their application for nanomaterials synthesis.

The translation of continuous-flow microreactor technology to the industrial environment has been limited by cost and complexity of the fabrication procedures and the requirement for specialised infrastructure. In the present study, we have developed a significantly more cost-effective and easy-to-perform fabrication method for the generation of optically transparent, continuous-flow reactors. The method combines 3D printing of master moulds with sealing of the PDMS channels' replica using a pressure-sensitive adhesive tape. Morphological characterisation of the 3D printed moulds was performed and reactors were fabricated with an approximately square-shaped cross-section of 1 mm2 . Notably, they were tested for operation over a wide range of volumetric flow rates, up to 20 ml/min. Moreover, the fabrication time (i.e., from design to the finished product) was <1 day, at an average material cost of ∼£5. The flow reactors have been applied to the production of both inorganic nanoparticles (silver nanospheres) and organic vesicular systems (liposomes), and their performance compared with reactors produced using more laborious fabrication methods. Numerical simulations were performed to characterise the transport of fluids and chemical species within the devices. The developed fabrication method is suitable for scaled-up fabrication of continuous-flow reactors, with potential for application in biotechnology and nanomedicine.