“…Rather than rely on the continuous flow of microchannels, discrete droplet systems can carry out a variety of parallel reactions at the same time, which can reduce the consumption of samples (Kardous et al, 2014); eliminate components such as microchannels, microvalves and micropumps; and reduce the risk of cross-contamination (Wang et al, 2009). The mixing technologies of droplets on an open surface mainly include electrowetting (Mugele et al, 2006;Paik et al, 2003;C. et al, 2021), magnetic (Roy et al, 2009), acoustic (Lee et al, 2016) and thermal (Tsai and Lin, 2002).…”