Figure 3.

(A) The principle of the “aptamer mixing method”. It can be seen that the detection ranges of aptamers, which have a high affinity (marked in red), medium affinity (marked in green) and low affinity (marked in blue) to the same biotarget, are narrow. However, the equivalent detection range of their mixture is wide. (B) The principle of the “conformation changing method”. By inducing the aptamer to change to the conformation with high affinity (Conformation 1), and the conformation with low affinity (Conformation 2), the detection range of the aptamer can shift to the low detection concentration area (Range 1) and the high detection concentration area (Range 2) respectively.