Design of a novel magnetic particles based electrochemical biosensor for organophosphate insecticide detection in flow injection analysis

• The present work described a novel configuration to integrate magnetic nanobeads into the flow based system.
• The sensor was aimed to achieve the reproducible and renewable sensing surface.
• The sensor was demonstrated for the detection of organophosphate insecticides using acetylcholinesterase.
• The system can be potentially applied for on-line assessment for any other analyte of interest.

The fabrication of transducer interfaces with improved electroanalytical performance is still a challenge in the field of advanced flow based electrochemical biosensors. The use of magnetic nanoparticles for such a purpose to replace the routinely used immobilization matrix including glass, membrane, polymer, gel beads, sol–gel supports, porous silicon matrix, and porous monolithic materials is well documented in the recent literature. However, the application of magneto-based methods is restricted due to lack of reproducibility and renewal of the sensor surface. To overcome these limitations, the present work described a novel configuration strategy to integrate magnetic nanobeads into the flow based system to achieve the reproducible and renewable sensing surface. The designed flow based sensor was demonstrated for the detection of organophosphate insecticides using acetylcholinesterase (AChE) enzyme. System parameters such as optimal bead injection and flow rate were studied prior to insecticides analysis. The system can be potentially applied for on-line assessment in a sensitive, automatic, inexpensive, continuous and simple way for any other analyte of interest.