Water-in-oil droplets are generated using Bio-rad droplet generator, and the oil phase is fluorosurfactant synthesised by myself dissolved in HFE-7500 with 2% W/W concentration. The water phase is negative control or positive control. The droplets generated were not uniform and some of them merged after ddPCR. I thought it maybe because of the low concentration, then I changed to use 4% concentration, results were similar. Therefore, how to make water-in-oil droplets generated by Bio-rad droplet generator uniform and enhance thermal stability of droplets using droplet digital PCR?