Simple, Cost-Effective 3D Printed Microfluidic Components for Disposable, Point-of-Care Colorimetric Analysis

The fabrication of microfluidic chips can be simplified and accelerated by three-dimensional (3D) printing. However, all of the current designs of 3D printed microchips require off-chip bulky equipment to operate, which hindered their applications in the point-of-care (POC) setting. In this work, we demonstrate a new class of movable 3D printed microfluidic chip components, including torque-actuated pump and valve, rotary valve, and pushing valve, which can be operated manually without any off-chip bulky equipment such as syringe pump and gas pressure source. By integrating these components, we developed a user-friendly 3D printed chip that can perform general colorimetric assays. Protein quantification was performed on artificial urine samples as a proof-of-concept model with a smartphone used as the imaging platform. The protein was quantified linearly and was within the physiologically relevant range for humans. We believe that the demonstrated components and designs can expand the functionalities and potential applications of 3D printed microfluidic chip and thus provoke more investigation on manufacturing lab-on-a-chip devices by 3D printers.