Gold coated ferric oxide nanoparticles based disposable magnetic genosensors for the detection of DNA hybridization processes.
In this article, a disposable magnetic DNA sensor using an enzymatic amplification strategy for the detection of specific hybridization processes, based on the coupling of streptavidin-peroxidase to biotinylated target sequences, has been developed. A thiolated 19-mer capture probe was attached to gold coated ferric oxide nanoparticles and hybridization with the biotinylated target was allowed to proceed. Then, a streptavidin-peroxide was attached to the biotinylated target and the resulting modified gold coated ferric oxide nanoparticles were captured by a magnetic field on the surface of a home-made carbon screen printed electrode (SPE). Using hydroquinone as a mediator, a square wave voltammetric procedure was chosen to detect the hybridization process after the addition of hydrogen peroxide. Different aspects concerning the assay protocol and nanoparticles fabrication were optimized in order to improve the sensitivity of the developed methodology. A low detection limit (31 pM) with good stability (RSD=7.04%, n=10) was obtained without the need of polymerase chain reaction (PCR) amplification.
Sensors and Photonics Unit, New Materials Department, CIDETEC-Center for Electrochemical Technologies, Parque Tecnológico de San Sebastián, P° Miramon, 196, E-20009 Donostia-San Sebastián, Guipuzcoa, Spain. oloaiza@cidetec.es
Óscar A
ÓA
Loaiza
Elena
E
Jubete
Estibalitz
E
Ochoteco
German
G
Cabañero
Hans
H
Grande
Javier
J
Rodríguez
D015374:Biosensing Techniques / Q000295:instrumentation*; D002874:Chromosome Mapping / Q000295:instrumentation*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D004209:Disposable Equipment; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005290:Ferric Compounds / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D017403:In Situ Hybridization / Q000295:instrumentation*; D008280:Magnetics / Q000295:instrumentation*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation
D020099:Coated Materials, Biocompatible; D005290:Ferric Compounds; C000499:ferric oxide; D006046:Gold