Probing and modulating the interactions of the DNAzyme with DNA-functionalized nanoparticles

DNA-functionalized gold nanoparticles are one of the most versatile bionanomaterials for biomedical and clinical diagnosis. Herein, we discovered that the performance of DNAzyme cleaving the substrate is highly related to its length. This intriguing phenomenon only appears at the interfaces of DNA-functionalized gold nanoparticles. We systematically investigated the causes of this phenomenon. We conjectured that the DNAzyme with extended nucleotides that do not match its substrate strand is vulnerable to non-specific adsorption, electrostatic repulsion, and steric hindrance. Based on our improved understanding of this phenomenon, we have successfully developed a highly sensitive and specific amplifiable biosensor to detect human apurinic/apyrimidinic endonuclease 1. (C) 2021 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.

Automated summary

DNA-functionalized gold nanoparticles are a versatile bionanomaterial for biomedical and clinical diagnosis. This study reveals that the performance of DNAzyme in cleaving substrate is closely related to its length, which only occurs at the interfaces of DNA-functionalized gold nanoparticles. The causes of this phenomenon, such as non-specific adsorption, electrostatic repulsion, and steric hindrance, are systematically investigated. Based on this improved understanding, a highly sensitive and specific amplifiable biosensor for detecting human apurinic/apyrimidinic endonuclease 1 is successfully developed.