Surfactant and oil formulations for monodisperse droplet emulsion PCR

Emulsion PCR has become a popular and widely applied method in biological research and clinical diagnostics to provide evenly amplified products and perform highly quantitative counting of target sequences. However, there is still a lack of information to support further development of appropriate water-in-oil emulsion formulations, which need to be both thermally and mechanically stable for digital amplification reactions. Here, we present a systematic survey of the oil and surfactant components of stable monodisperse w/o emulsions suitable for use with our previously developed micro-capillary array (MiCA)-based centrifugal emulsion generation method. Our findings show that a binary formula consisting of isopropyl palmitate and a silicone copolymer demonstrated the best performance, and provided a general guideline for the development of emulsion systems for digital PCR and emulsion amplification applications.