3D Stereolithography (SLA) Printing-Based Micro-Fabrication Using Custom Polymer Resin Chemistry for Rapid Prototyping of Microfluidic Chips and Component

We report the use of an off the shelf and inexpensive desktop masked stereolithography (MSLA) based 3D printer to (i) fabricate complex structures with sub 100 micron-sized features with 3D printed molds for conventional PDMS casting, (ii) fabricate unibody chips with imbedded channels, and (iii) Engineer a finger-actuated displacement pump that can transport and meter precise quantities of fluids into a microfluidic chip. Parameters such as print direction, support structure, and light exposure time were found to be important factors that determine the optimal conditions to achieve the smallest possible print resolution consistently. We also present a custom UV curable resin that enables us to fabricate transparent prints with tunable compressibility and porosity. We demonstrate the fabrication of multi-layered microfluidic channels, droplet generators, and DNA amplification chips. The convenience and swiftness of our proposed technique enables one to go from an “idea stage” to a “fabricated microfluidic chip” within ~hours as opposed to traditional clean room-based microfabrication (~days), which could drastically lower the barrier to entry and greatly accelerate lab-on-a-chip research.