Stable Colloidosomes Formed by Self-Assembly of Colloidal Surfactant for Highly Robust Digital PCR

As the third-generation nucleic acid amplification technology, digital polymerase chain reaction (PCR) has been widely adopted in the analysis of nucleic acids. However, further application of this powerful technology is hindered due to the limitation of surfactants. Here, for the first time, we propose the use of colloidosomes self-assembled from fluorinated silica nanoparticle for digital PCR to address this limitation. A one-step fluorinated silica nanoparticle synthesis method is proposed, which is much more convenient and reproducible compared with the synthesis of conventional fluorine-based surfactants. Fluorinated silica nanoparticles facilitate the formation of colloidosomes with excellent stability capable of enduring the rapid temperature changes associated with the PCR and avoiding material exchange (cross-talk) between droplets for high-fidelity analysis. The colloidosome digital PCR method was developed using these colloidosomes as highly parallel reactors for single-copy nucleic acid amplification and rare mutant detection. The method is robust and accurate, and it offers possibilities for a great variety of applications, such as gene expression studies, single cell analysis, and circulating tumor DNA detection.