Portable smartphone-based aptasensor for nitrofuran detection

A portable electrochemical aptasensor for the detection of nitrofuran (NF) was developed. Aptamer-conjugated gold nanoparticles (Apt-AuNPs) were immobilized on a chitosan (CS) thin film electrodeposited on a screen-printed carbon electrode (SPCE). The modified electrode was connected to a smartphone-controlled near-field communication (NFC) potentiostat. The electrochemical aptasensor determined NF concentration using cyclic voltammetry (CV) and chronoamperometry (CA) techniques. Under optimal conditions, the developed aptasensor exhibited high sensitivity (11.26 ± 0.38 μA L/μg), a wide linear range (0.005 to 0.08 μg/L and 0.08 to 4.0 μg/L), and a low detection limit (0.004 μg/L). Our construction demonstrated excellent stability for NF, with a reduction in current of less than 10 % even after 330 days. Reproducibility (%RSD = 2.19 %) was good, and the device was portable, simple, and selective. Therefore, this aptasensor platform was applied as a smartphone-based wireless NFC potentiostat for NF detection in shrimp pond water and shrimp samples.