Microfluidics materials are of various types and application-specific. PDMS is one of the most preferred and cost-effective solutions for research and low-volume manufacturing. After having the mold, PDMS replicas are generated by a technique called soft-lithography. This protocol describes the preparation of PDMS microchannels using SU8 molds, 3D Printed resin molds, and/or metal molds by the soft lithography technique, SLA printing, or CNC machining.
Microfluidics materials are of various types and application-specific. PDMS is one of the most preferred and cost-effective solutions for research and low-volume manufacturing. After having the mold, PDMS replicas are generated by a technique called soft-lithography. This protocol describes the preparation of PDMS microchannels using SU8 molds, 3D Printed resin molds, and/or metal molds by the soft lithography technique, SLA printing, or CNC machining.
This paper presents a novel latchable phase-change actuator that can potentially be used for flow valving and gating in portable lab-on-a-chip systems, where minimal energy consumption is required. The actuator exploits a low melting-point paraffin wax, whose solid-liquid phase changes allow the closing and opening of fluid flow through deformable microchannels. Flow switching is initiated by melting of paraffin, with an additional pneumatic pressure required for flow switching from open to closed state. After paraffin solidifies the switched state is subsequently maintained passively without further consumption of energy. The actuator can be fabricated from PDMS through the multilayer soft lithography technique. Testing results demonstrate that the actuator has a response time about 60-100 sec for flow switching, and can passively hold a microvalve closed under pressures up to 35 kPa.
Micro/Nano Patterning on Polymers Using Soft Lithography Technique