Universal Design of Structure-Switching Aptamers with Signal Reporting Functionality.
Anal Chem
; 91(22): 14514-14521, 2019 11 19.
Article
em En
| MEDLINE
| ID: mdl-31614078
ABSTRACT
Structure-switching aptamers (SSAs) offer a promising recognition element for sensor development. However, the generation of SSAs via in vitro aptamer selection technologies or postselection engineering is challenging. Inspired by the two-domain structure of antibodies, we have devised a simple, universal strategy for engineering aptamers into SSAs with signal reporting functionality. These constructs consist of a "constant" domain, comprising a split DNAzyme G-quadruplex (G4) region for signal transduction, and a "variable" domain, comprising an aptamer sequence capable of specific target binding. In the absence of target, the G4-SSA construct folds into a parallel G4 structure with high peroxidase catalytic activity. Target binding disrupts the G4 structure, resulting in low enzymatic activity. We demonstrate that this change in DNAzyme activity enables sensitive and specific colorimetric detection of diverse targets including Hg2+, thrombin, sulfadimethoxine, cocaine, and 17ß-estradiol. G4-SSAs can also achieve label-free fluorescence detection of various targets using a specific G4-binding dye. We demonstrate that diverse aptamers can be readily engineered into G4-SSA constructs independent of target class, binding affinity, aptamer length, or structure. This design strategy could broadly extend the power, accessibility, and utility of numerous SSA-based biosensors.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Técnicas Biossensoriais
/
DNA Catalítico
/
Aptâmeros de Nucleotídeos
Idioma:
En
Revista:
Anal Chem
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
China