The repeated fueling process actively transports molecules against a concentration gradient. To further support this observation, we conducted an experiment in which Cbz-D was added to both the sender and receiver (Fig. ). After fueling the sender, we observed a 20-30% increase in Cbz-D in the receiver over eight days, while the sender initially decreased by 50% but gradually recovered to 70-80% over eight days (Fig. ). Noteworthy, we demonstrated that chemically fueled transport can occur also across the hydrophobic barrier dichloromethane (Fig. ).