Ma et al. have thoroughly investigated the injection molding of PMMA-based microfluidic devices using a horizontal single screw injection molding machine capable of performing each injection cycle in 45 s (Figure ) . They set the injection pressure at 120 MPa and the speed ranged between 200 mm/s to 400 mm/s. The injection was performed at 60 ℃ using an oil mold temperature controller. In another study, Kim et al. applied 5.5 MPa injection pressure and clamping force of 130 tons to create PS microfluidic channels at 220 ℃ in 15 s, and used the device for single cell analysis . Using the same injection molding parameters, Ko et al. fabricated an open circular microfluidic chip made of PS for ocular angiogenesis applications . Injection molding was also adopted in Viehrig et al.'s work to form nanocones in COC through a nickel master mold (Figure ) . The device was employed for SERS sensing applications.