This report presents the results of ternary alloy quantum dots (TQDs) manufacturing and its superior optical properties to fabricate the biosensor for pesticide detection. The explanation for the changes in PL intensity based on the change of electronic charges that alters the pH value of the surrounding environment, and the types of interaction on the surface of CdZnSe/ZnS TQDs were discussed. We show the decomposition process of the indicator (ATCh) with the catalysis from acetyl cholinesterase enzyme (AChE) that inhibited by organophosphorus and carbamate pesticides including Trichlorfon (TF), Cypermethrin (CH), Abamectin (AT), and Carbosulfan (CS) with concentrations from ppm to 10 ppm. | Communications in Physics, Vol. 24, No. 3 (2014), pp. 225-231 DOI: SENSITIVE ORGANOPHOSPHORUS AND CARBAMATE PESTICIDES BIOSENSOR BASED ON ACETYLCHOLINESTERASE AND CdZnSe/ZnS TERNARY ALLOY QUANTUM DOTS NGUYEN NGOC HAI, NGUYEN HAI YEN, DUONG THI GIANG, NGUYEN DUC NHAT, PHAM THU NGA, AND DAO TRAN CAO Institute of Materials Science, Vietnamese Academy of Science and Technology E-mail: haidhsphn@ Received 07 April 2014 Accepted for publication 30 June 2014 Abstract. This report presents the results of ternary alloy quantum dots (TQDs) manufacturing and its superior optical properties to fabricate the biosensor for pesticide detection. The explanation for the changes in PL intensity based on the change of electronic charges that alters the pH value of the surrounding environment, and the types of interaction on the surface of CdZnSe/ZnS TQDs were discussed. We show the decomposition process of the indicator (ATCh) with the catalysis from acetylcholinesterase enzyme (AChE) that inhibited by organophosphorus and carbamate pesticides including Trichlorfon (TF), Cypermethrin (CH), Abamectin (AT), and Carbosulfan (CS) with concentrations from ppm to 10 ppm. Keywords: pesticide, biosensors, ternary alloy quantum dots, photoluminescence. I. INTRODUCTION Organophosphorus (OP) compounds, carbamates, or neonicotinoids are widely used in plant protection because of the efficiency for insect killing, easy synthesis, and low cost. The above pesticide residues are harmful to the environment, human health, and animals through the nervous system poisoning by the way of inhibiting the activity of AChE, the most important enzyme involved in nerve transmission [1, 6]. The principal role of AChE is the termination of nerve impulse transmission at cholinergic synapses by rapid hydrolysis of the neurotransmitter acetylcholine (ACh) – each molecule of AChE degrades about 25000 molecules of ACh per second, leading to in vivo accumulation of ACh, and
