Microfabricated Platform for Nanoscale Flow Sensing and Control

In this paper we describe a microfabricated platform for nanoscale flow sensing and control. Two custom-built pneumatically-driven pumps were used to deliver two different fluids into our microfluidic chip. The two liquids were mixed on-chip and the flow rate and composition of the resulting liquid was measured. Flow rate measurements were accurate within a few nL/min and the composition within 0.2%. In this paper, composition is defined as the makeup (by volume and expressed as a percentage) of a binary mixture. Feedback from the sensors was used to control the pumps in order to produce the desired flow profiles.