Bispecific aptamer-initiated 3D DNA nanomotor biosensor powered by DNAzyme and entropy-driven circuit for sensitive and specificity detection of lysozyme

Dynamic DNA nanodevices have gained tremendous attention due to their extraordinary inherent functionality and advantages, however, dynamic DNA nanodevices-based biosensors are still challenging due to their high reliance on proteases and limited amplification capabilities. Herein, exploiting bispecific aptamer as initiators for the first time, we developed a three-dimensional (3D) DNA nanomotor biosensor powered by DNAzyme and entropy-driven circuit for sensitive and specific detection of lysozyme, in which walking and rolling strategies are efficiently integrated to achieve excellent signal amplification capability. Benefiting from the high selectivity of bispecific aptamer, the 3D DNA nanomotor biosensor can respond to lysozyme with high specificity and operate at high speed to release signals. The whole process is independent of protease, avoiding the influence of adverse environment on the operation stability. Under optimal conditions, it can achieve a limit of detection as low as 0.01 pg/mL with an excellent linear range of 0.05 pg/mL–500 ng/mL for lysozyme. Furthermore, the proposed strategy revealed high accuracy in the analysis of real samples, indicating a great potential for the application of nanomotor biosensors to the detection of non-nucleic acid targets.