Method and system for ultra-high dynamic range nucleic acid quantification

Abstract

A method of quantifying nucleic acids in a sample includes generating a plurality of droplets in oil within a microfluidic device, wherein at least some of the droplets comprise a nucleic acid, amplification reagents, and a fluorescent probe or dyes contained therein. The droplets are delivered to a collection chamber to form an array of droplets. The droplets are subject to thermal cycling within the collection chamber a plurality of times to perform nucleic acid amplification within the droplets. The array of droplets is imaged during the plurality of thermal cycles as well as at a thermal cycle endpoint. An initial concentration of nucleic acid in the sample is calculated based on at least one of: a ratio of aqueous phase droplets exhibiting fluorescence within the array at the thermal cycle endpoint or a cycle threshold (Ct) of one or more aqueous phase droplets within the array.