DNA-Based Sensor for the Detection of an Organophosphorus Pesticide: Profenofos

Sensors

Robert Săndulescu¹  Cecilia Cristea¹  Giulia Selvolini²  Giovanna Marrazza²  Oana Hosu²  Ioana Băjan² 

[1] Department of Analytical Chemistry, University of Medicine and Pharmacy “Iuliu Haţieganu”, 4 Pasteur Street, 400349 Cluj-Napoca, Romania;Department of Chemistry “Ugo Schiff”, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino (FI), Italy;

关键词: screen-printed electrodes;    aptasensor;    nanoparticles;    organophosphorus pesticide;    profenofos;   

DOI  :  10.3390/s18072035

来源: DOAJ

【 摘 要 】

In this work, we propose an electrochemical DNA aptasensor for the detection of profenofos, an organophosphorus pesticide, based on a competitive format and disposable graphite screen-printed electrodes (GSPEs). A thiol-tethered DNA capture probe, which results to be complementary to the chosen aptamer sequence, was immobilised on gold nanoparticles/polyaniline composite film-modified electrodes (AuNPs/PANI/GSPE). Different profenofos solutions containing a fixed amount of the biotinylated DNA aptamer were dropped onto the realized aptasensors. The hybridisation reaction was measured using a streptavidin-alkaline phosphatase enzyme conjugate, which catalyses the hydrolysis of 1-naphthyl -phosphate. The 1-naphtol enzymatic product was detected by means of differential pulse voltammetry (DPV). The aptasensor showed itself to work as a signal off sensor, according to the competitive format used. A dose response curve was obtained between 0.10 μM and 10 μM with a detection limit of 0.27 μM.

【 授权许可】

Unknown