Vapor-tight ice-valving in centrifugal microfluidics for PCR applications

Abstract

This paper reports a novel application of ice-valving in a centrifugal platform and its utilization for PCR amplification. These ice-valves form as a result of freezing small plugs of fluid in the channels directly above cooled thermoelectric modules. A reversible, vapor-tight seal, strong enough to withstand the sustained high temperatures due to PCR thermocycling can be formed in as little as 5 seconds. In order to demonstrate the effectiveness of these vapor-tight valves, PCR thermocycling was performed on a stationary centrifugal disc (CD), with no appreciable sample fluid loss.