Development of aptasensor for chlorpyrifos detection using paper-based screen-printed electrode.

Novel Carbon quantum dots-graphite composite ink-based Screen-printed electrodes (CQDs/SPEs) were used to assemble a highly sensitive electrochemical aptasensor against chlorpyrifos (CPF). The aptasensor showed a broad linear range from 1 pM (0.445 ng/ml) to 500 nM (0.22 mg/ml) with a detection limit (LOD) 0.834 pM (0.37 ng/ml); sensitivity 21.39 μA pM−1 cm− 2 and with good linearity of R2 = 0.973. Moreover, the aptasensor's showed better selectivity among few other pesticides. Further, the aptasensor electrode showed high stability for five months when stored at 4 °C. In the final step, the aptasensor's ability to identify CPF in real samples was evaluated on spiked potato (Solanum tuberosum) extract samples. Potato extract spiked with CPF in the electrochemical aptasensing platform showed excellent linearity of R2 = 0.981. The developed aptasensor showed good response to without spiked potato extract with increasing volumes. Hence, the developed aptasensor demonstrated reasonable applicability in real food and agriculture samples. • Chlorpyrifos (CPF), an organophosphate pesticide, is known for detrimental effects on environment raising global health concern. • Electrochemical based disposable screen printed aptasensor is developed for the detection of chlorpyrifos pesticide. • The CQDs/SPE aptasensor was fabricated using carbon quantum dots (CQDs) through drop cast method. • The aptasensor exhibited a wide linear range (1 pM-500 nM) with LOD (0.834 pM) and high sensitivity (21.39 μA pM−1 cm− 2). [ABSTRACT FROM AUTHOR]