~ 3199 ~ International Journal of Chemical Studies 2018; 6(2): 3199-3205 P-ISSN: 2349–8528 E-ISSN: 2321–4902 IJCS 2018; 6(2): 3199-3205 © 2018 IJCS Received: 10-01-2018 Accepted: 14-02-2018 Pragati Joshi Department of Chemistry, College of Basic Science and Humanities, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S Nagar, Uttarakhand, India Anjali Bisht Department of Chemistry, College of Basic Science and Humanities, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S Nagar, Uttarakhand, India Tanvi Tyagi Department of Chemistry, College of Basic Science and Humanities, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S Nagar, Uttarakhand, India Sameena Mehtab Department of Chemistry, College of Basic Science and Humanities, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S Nagar, Uttarakhand, India MGH Zaidi Department of Chemistry, College of Basic Science and Humanities, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S Nagar, Uttarakhand, India Correspondence Pragati Joshi Department of Chemistry, College of Basic Science and Humanities, G.B. Pant University of Agriculture and Technology, Pantnagar, U.S Nagar, Uttarakhand, India Electrochemical sensor for the detection of pesticides in environmental sample: A review Pragati Joshi, Anjali Bisht, Tanvi Tyagi, Sameena Mehtab and MGH Zaidi Abstract Many of the pesticides are acutely toxic and have lasting effect on human health. The primary reason for organophosphate (OP) toxicity is its inhibition of the acetyl cholinesterase (AChE) enzyme. Significant work is reported on electrochemical sensors for OP detection and they have been proven as an inexpensive, simple and versatile analytical tool. They have found a vast range of important applications in the fields of clinical, industrial, environmental and agricultural analyses. Their sensitivity, reproducibility and specific selectivity towards target OP molecules can be improved by applying different coating materials at electrode surface. In this review focus is on the coating materials for the modification of working electrodes surface to use it widely as sensors for electroanalytical strategy for many sensing applications requiring highly compatible and properly functionalized surfaces to anchor the recognition material. Graphical Abstract: Schematic illustration of the stepwise AChE biosensor fabrication process and immobilized AChE inhibition in pesticide solution Keywords: organophosphate, acetylcholinesterase, electrochemical sensor Introduction Pesticide is an organic toxic substance or mixture of substances used to prevent, destroy, repel, or mitigate insects, bacteria, weeds, nematodes, rodents that causes harm [1] . There are six major classes of pesticides including organophosphates (OPs), carbamates, organochlorines, pyrethroid, metal and organometal pesticides [2] . They are widely used in agriculture to improve yield and to protect seeds and crops before and after harvesting, leading to an increase in its application over the years but the pesticide residues are contaminating our environment and may enter into the food chain through water, air and soil and cause serious problems to environment and human health [1] . Organophosphates pesticides (OPs) are usually esters, amides or thiol derivatives of phosphoric, phosphonic or phosphinic acids. They came into existence in 1932 and some organophosphates due to their acute toxicity were used in 2 nd world war as nerve agents [3] . OPs are widely used in agriculture for crop protection and pest control due to their high