Development of a Novel Optical Biosensor for Detection of Organophoshorus Pesticides Based on Methyl Parathion Hydrolase Immobilized by Metal-Chelate Affinity

Sensors

Wensheng Lan¹  Guoping Chen²  Feng Cui³  Feng Tan³  Ran Liu² 

[1] Shenzhen R&D Key Laboratory of Exotic Pest Detection Technology, Animal & Plant Inspection and Quarantine Technical Center, Shenzhen Entry-Exit Inspection and Quarantine Burea, 1011 Fuqiang Road, Shenzhen 518045, China; E-Mail:;State Key Laboratory of ASIC & System and School of Microelectronics, Fudan University, 220 Handan Road, Shanghai 200433, China; E-Mails:;State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Science, Beijing 100101, China; E-Mails:

关键词: optical biosensor;    methyl parathion hydrolase;    organophosphorus compound;    metal-chelate affinity;   

DOI  :  10.3390/s120708477

来源: mdpi

【 摘 要 】

We have developed a novel optical biosensor device using recombinant methyl parathion hydrolase (MPH) enzyme immobilized on agarose by metal-chelate affinity to detect organophosphorus (OP) compounds with a nitrophenyl group. The biosensor principle is based on the optical measurement of the product of OP catalysis by MPH (p-nitrophenol). Briefly, MPH containing six sequential histidines (6× His tag) at its N-terminal was bound to nitrilotriacetic acid (NTA) agarose with Ni ions, resulting in the flexible immobilization of the bio-reaction platform. The optical biosensing system consisted of two light-emitting diodes (LEDs) and one photodiode. The LED that emitted light at the wavelength of the maximum absorption for p-nitrophenol served as the signal light, while the other LED that showed no absorbance served as the reference light. The optical sensing system detected absorbance that was linearly correlated to methyl parathion (MP) concentration and the detection limit was estimated to be 4 μM. Sensor hysteresis was investigated and the results showed that at lower concentration range of MP the difference got from the opposite process curves was very small. With its easy immobilization of enzymes and simple design in structure, the system has the potential for development into a practical portable detector for field applications.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland.