Construction of logic gates with the fluorene-based small molecule/DNA probes

Fluorene-based small molecules (FSMs) have optical properties and can interact with DNA. In this paper, the integrated INH and AND gates operating in parallel are developed with the fluorene-based small molecule (FSM)/DNA probe. They are activated by taking advantage of the two-step fluorescence resonance energy transfer (FRET) process and the sequence-recognition mechanism of DNA. Then, a NOT gate is obtained with a molecular beacon-like probe (FSM-MB) by using the FSM as the fluorophore. Moreover, the NOT gate based on the FSM-MB probe can be used as a biosensor and has potential applications in label-free detection of target molecules.