Rapid Prototyping of Multi-Functional and Biocompatible Parafilm-Based Microfluidic Devices by Laser Ablation and Thermal Bonding.

In this paper, we report a simple, rapid, low-cost, biocompatible, and detachable microfluidic chip fabrication method for customized designs based on Parafilm. Here, Parafilm works as both a bonding agent and a functional membrane. Its high ultimate tensile stress (3.94 MPa) allows the demonstration of high-performance actuators such as microvalves and micropumps. By laser ablation and the one-step bonding of multiple layers, 3D structured microfluidic chips were successfully fabricated within 2 h. The consumption time of this method (2 h) was 12 times less than conventional photolithography (24 h). Moreover, the shear stress of the PMMA-Parafilm-PMMA specimens (0.24 MPa) was 2.13 times higher than that of the PDMS-PDMS specimens (0.08 MPa), and 0.56 times higher than that of the PDMS-Glass specimens (0.16 MPa), showing better stability and reliability. In this method, multiple easily accessible materials such as polymethylmethacrylate (PMMA), PVC, and glass slides were demonstrated and well-incorporated as our substrates. Practical actuation devices that required high bonding strength including microvalves and micropumps were fabricated by this method with high performance. Moreover, the biocompatibility of the Parafilm-based microfluidic devices was validated through a seven-day cultivation. This reported fabrication scheme will provide a versatile platform for biochemical applications and point-of-care diagnostics.