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Published on: October 6, 2022
Highly Sensitive Biosensing Applications of a Magnetically Immobilizable Covalent G-Quadruplex-Hemin DNAzyme
Yun Chen1, Dehui Qiu1, Xiaobo Zhang1
1State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China.
Abstract:
G-quadruplex/hemin (G4/hemin) DNAzymes are biosensing systems, but their application remains limited by an overall low activity and a rather high level of unwarranted background reactions. Here, these issues were addressed through the rational design of F3T-azaC-hemin, a G4-based construct in which the hemin is covalently linked to the G4 core and its binding site flanked with a nucleotide activator, here d(T-azaC). This design led to a G4-DNAzyme whose performances have been ca. 150-fold increased compared to the parent G4-based system. The utility of F3T-azaC-hemin was demonstrated here through the ultrasensitive chemiluminescent detection of miRNA-221. The limit of detection (LOD) has been decreased to the femtomolar range, making it a new and highly efficient molecular tool in the biosensing technology field.
