Figure 4. Tunable threshold can be implemented with drain templates at the cost of amplification rate:

50 nM of autocatalytic template βtoβ was incubated with 20, 25 or 30 nM of drain template drainβ and various concentrations of trigger β; the hashed bars indicate the range, within which the threshold trigger concentration required to switch the system to the high state can be found; the blue dots and error bars, respectively, indicate the mean and s.d. of the maximum amplification rate Vmax measured in the presence of 1, 3 and 9 nM of trigger β.