Photopolymerized check valve and its integration into a pneumatic pumping system for biocompatible sample delivery.

In this paper, we present a simple check valve whose operation mimics that of venous valves. Our check valve has a mono-leaflet and is constructed via an in situ fabrication method inside the PDMS platform. For the smooth operation of the valve's leaflet, the elasticity and the shape of the leaflet and the lubrication between the leaflet and the channel surface are important. We used 4-hydroxybutyl acrylate (4-HBA) as an elastic and photopolymerizable leaflet material. We mixed the triton X-100 with the 4-HBA pre-polymer solution for the adequate lubrication of the leaflet. We constructed the micro-pumping system by combining two venous-like check valves with an oscillating polymeric diaphragm driven by pneumatic force, and measured the flow rate according to the change of pumping frequency. We also investigated the pump's feasibility as a delivery system of biocompatible materials by using mouse embryo fibroblast cells.