Abstract

High-Precision Overmolding as New Fully Automated, Integrated Method to Seal Microfluidic Devices for Demanding High-Volume Applications

Andreas Schäfert, Director Business Development Medical Devices, Wilhelm Weber GmbH

A new process is presented enabling to fabricate complete microfluidic chips within a multi-component injection molding machinery. For the production of the microfluidics chips the microchannel plate and the cover plate are produced by injection molding in 2 cavities of one rotary tool while in contrast to the conventional microchannel fabrication the channels are created by the surrounding walls defining the dimensions and shape of channels in between. Interfaces for inlet and outlet like LUER cones can be integrated into the mold. It is also possible to perform a physical surface treatment. For the bonding the rotating system places the back sheet on top of the wall structure of the front sheet and the area between the 2 sheets is overmolded while the channels remain free as they are protected by the walls produced in the first step. The polymer for overmolding can be the same or another than used for the sheets. Optionally components like electronics are implemented into the overmolding process. By this technique, a ready to use chip can produced in less than 30 seconds in one single machine. Bonding strengths and tightness have been tested successfully and first high-volume applications for medical dosing are launched.