Design Of Colorimetric Logic Gate And Biosensor Based On G-Quadruplex Dnazyme

DNA is not only a stable genetic material,but also has the advantages of specific hybridization,super parallel computing,high density information storage and smallness.Therefore,DNA is widely used in the field of nanotechnology.It can be used to construct manipulated nanostructures,but also can be used as a tool for molecular computing.In this study,G-quadruplex DNAzyme was used as the basic element of the molecular logic gate and biosensor to construct a simple,economical and safe colorimetric logic gate and colorimetric biosensor.The sequence design,experimental simulation,experimental design,analysis and discussion have been given.The specific research contents are as follows:Based on the formation and dissociation of G-quadruplex DNAzyme and the catalytic reaction of G-quadruplex DNAzyme,a new and efficient colorimetric logic gate model was designed,which includes YES,NOT,AND,OR,NAND,NOR gate.With the help of two DNA strands,the different states of YES gate were linked to construct the cycle transformation driven by two DNA strands as fuel.The DNA sequences were designed according to the model.The DNA sequences of logic gates were preliminarily verified by Nupack simulation and were further verified by polyacrylamide gel electrophoresis.The design of logic gates was optimized from multiple dimensions of time,temperature,and concentration.The colorimetric analysis and absorbance curves visually demonstrated the output signals of logic gates and validated the effectiveness of the colorimetric logic gate models.The colorimetric logic gate is cascaded as a basic logic unit and a novel colorimetric logic circuit and a logic computing system can be constructed.Based on the principle of catalytic reaction of G-quadruplex and the amplification technology of hybridization chain reaction(HCR),a novel,specific,and highly sensitive biosensor model was designed.According to the model,the DNA sequences were designed from three aspects: design optimization of biosensor,specific recognition and sensitivity.The DNA sequences of logic gates were preliminarily verified by Nupack simulation,and the specific recognition and high sensitivity of the biosensor for the target molecule were further verified by polyacrylamide gel electrophoresis.The design of biosensor was optimized from two dimensions of time and concentration.The absorbance curves visually demonstrated the output signals of logic gates and validated the effectiveness of the colorimetric logic gate models.The recognition of biosensor for target molecule was further validated through the absorbance curve.