Antifouling electrochemical sensor-based on mesoporous silica film for imidacloprid detection in Traditional Chinese medicine

The performance of electrochemical sensors in complicated samples is confined by electrode fouling and the development of antifouling electrode interface is vital for improving their sensing performance. Herein, an efficient antifouling electrochemical sensor was constructed based on mesoporous silica film (MSF) coating modified graphene oxide/glass carbon electrode (GO/GCE). MSF coating was directly grown on GO/GCE by electroassisted self-assembly (EASA) method within a few seconds and GO was reduced to electrochemically reduced graphene oxide (ErGO) simultaneously. Owing to the electrocatalytic activity of ErGO and electrostatic pre-enrichment of MSF toward imidacloprid (IMI), the as-obtained MSF/ErGO/GCE exhibits excellent response to IMI in two wide concentration ranges (1.0 μg mL-1 50 μg mL-1 50 μg mL-1–400 μg mL-1) with a low limit of detection of 0.3 μg mL-1(1.1 bvM)Furthermore, the antifouling electrochemical sensor possesses the capability of direct determination IMI in untreated carthamus tinctorius (a Traditional Chinese medicine, TCM).