A DNAzyme-catalyzed label-free aptasensor based on multifunctional dendrimer-like DNA assembly for sensitive detection of carcinoembryonic antigen.
Biosens Bioelectron
; 194: 113618, 2021 Dec 15.
Article
en En
| MEDLINE
| ID: mdl-34530373
ABSTRACT
Carcinoembryonic antigen (CEA) is an important malign tumor marker. In this study, a simple, label-free and antibody-free aptasensor was fabricated based on a multifunctional dendrimer-like DNA nanoassembly. The DNA nanoassembly was embedded with multiple G-quadruplex DNAzyme motifs and a hanging CEA aptamer motif. It was prepared from short DNA sequences by autonomous-assembly. The aptasensor was prepared simply by self-assembly of a capture DNA (cpDNA) on a gold electrode, followed by hybridization with a CEA aptamer (AptGAC-P). CEA as a model target was detected through competitive binding of CEA with AptGAC-P, exposing cpDNA to bind with the DNA nanoassembly. The detection process only contains 2 incubation steps. The high load of G-quadruplex DNAzyme motifs and their catalytic activity resulted in an amplified and label-free differential pulse voltammetry (DPV) electrochemical signal. The peak current correlated linearly with the CEA concentration, with a linear range of 2-45 ng mL-1, and an LOD value of 0.24 ng mL-1. The aptasensor showed high specificity and reproducibility, and retained 96.5% of detection signal intensities after 31 days of storage. The recovery rates for spiked CEA in human serum were within 100 ± 5%, and the coincidence rates for clinical human serum samples with ELISA kits were 80.7-111%. Conceivably, possessing simplicity, sensitivity, reproducibility, storage stability, and accuracy, the aptasensor should be a very prominent and applicable tool for clinical CEA detection and cancer diagnosis, and is promisingly applicable as a platform for detecting other targets of interests.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Técnicas Biosensibles
/
ADN Catalítico
/
Dendrímeros
/
Aptámeros de Nucleótidos
Tipo de estudio:
Diagnostic_studies
/
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
Biosens Bioelectron
Asunto de la revista:
BIOTECNOLOGIA
Año:
2021
Tipo del documento:
Article
País de afiliación:
China