Electrochemical DNA sandwich biosensor based on enzyme amplified microRNA-21 detection and gold nanoparticles.
In this work, a novel electrochemical biosensor for miRNA-21 determination, involving a sandwich hybridization assay onto gold nanoparticles modified pencil graphite electrode (PGE) and enzyme signal amplification was reported. The thiol terminated capture probe 1 (SH-P1) was immobilized on the electrode through AuS interaction. In the presence of target miRNA-21, SH-P1 hybridized with the first part of the target, however, the second part hybridizes with a biotinylated probe P2 (B-P2). Then, a streptavidin-conjugated alkaline phosphatase was immobilized by a specific binding of avidin-B-P2. The enzyme catalyzed the electro-inactive α-naphtyl phosphate to an electro-active α-naphtol. The miRNA-21 detection was achieved through the changes of α-naphtol oxidation signals observed at +0.12V vs Ag/AgCl with Differential Pulse Voltammetry. Under the optimal detection conditions, the biosensor exhibited selective and sensitive detection with a linear range from 200pM to 388nM and the detection limit was 100pM (10fmol in 100μL).
Laboratoire Génie des Procédés et Environnement, Faculté de Sciences et Techniques Mohammedia, University Hassan II of Casablanca, Morocco.
Jihane
J
Mandli
Laboratoire Génie des Procédés et Environnement, Faculté de Sciences et Techniques Mohammedia, University Hassan II of Casablanca, Morocco.
Hasna
H
Mohammadi
Laboratoire Génie des Procédés et Environnement, Faculté de Sciences et Techniques Mohammedia, University Hassan II of Casablanca, Morocco. Electronic address: azizamine@yahoo.fr.
Aziz
A
Amine
D000469:Alkaline Phosphatase / Q000737:chemistry / Q000378:metabolism*; D001483:Base Sequence; D015374:Biosensing Techniques / Q000379:methods*; D004563:Electrochemistry; D006046:Gold / Q000737:chemistry*; D006801:Humans; D061986:MCF-7 Cells; D053768:Metal Nanoparticles / Q000737:chemistry*; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D015203:Reproducibility of Results
C524940:MIRN21 microRNA, human; D035683:MicroRNAs; D006046:Gold; D000469:Alkaline Phosphatase
Biosensor; Enzyme signal amplification; Gold nanoparticles; Pencil graphite electrode; Sandwich hybridization assay; miRNA-21