DNAzyme-Based Biosensors: Immobilization Strategies, Applications, and Future Prospective

作者：Shadman Khan, Brenda Burciu, Carlos D. M. Filipe, Yingfu Li, Kristen Dellinger, Tohid F. Didar · 发表于：ACS Nano · 年份：2021 · DOI：10.1021/acsnano.1c04327 · 被引用次数：326 · 研究领域：Advanced biosensing and bioanalysis techniques、Biosensors and Analytical Detection、Electrochemical Analysis and Applications

Since their discovery almost three decades ago, DNAzymes have been used extensively in biosensing. Depending on the type of DNAzyme being used, these functional oligonucleotides can act as molecular recognition elements within biosensors, offering high specificity to their target analyte, or as reporters capable of transducing a detectable signal. Several parameters need to be considered when designing a DNAzyme-based biosensor. In particular, given that many of these biosensors immobilize DNAzymes onto a sensing surface, selecting an appropriate immobilization strategy is vital. Suboptimal immobilization can result in both DNAzyme detachment and poor accessibility toward the target, leading to low sensing accuracy and sensitivity. Various approaches have been employed for DNAzyme immobilization within biosensors, ranging from amine and thiol-based covalent attachment to non-covalent strategies involving biotin-streptavidin interactions, DNA hybridization, electrostatic interactions, and physical entrapment. While the properties of each strategy inform its applicability within a proposed sensor, the selection of an appropriate strategy is largely dependent on the desired application. This is especially true given the diverse use of DNAzyme-based biosensors for the detection of pathogens, metal ions, and clinical biomarkers. In an effort to make the development of such sensors easier to navigate, this paper provides a comprehensive review of existing immobilization strategies,...