A droplet generating system includes a reservoir configured to receive an organic fluid and an aqueous fluid, a barrier separating the reservoir into a first reservoir portion and a second reservoir portion, a tube, and an indexer. The barrier is capable of preventing the aqueous fluid from entering the second reservoir portion from the first reservoir portion. The tube is disposed near the barrier, and the tube has a microfluidic channel. The indexer guides the aqueous fluid and the organic fluid into the microfluidic channel so as to form droplets of the aqueous fluid.