Strand displacement amplification (SDA) is an isothermal DNA amplification technique. Herein, we developed a novel SDA system, designated All-U-Want SDA (AUW-SDA), which was used as a signal amplification strategy for the construction of nucleic acid detection biosensors. AUW-SDA is capable of target turnover and can be utilized for detection of nucleic acid sequences without available 3'-ends. Of particular significance is the ability of AUW-SDA to generate a substantial number of programmable sequences in accordance with the specifications of the sensor signal output methods, irrespective of the sequence of the target nucleic acid. We used the