Fiber‐Optic Enzyme Biosensor for Direct Determination of Organophosphate Nerve Agents

A fiber‐optic enzyme biosensor for the direct measurement of organophosphate nerve agents was developed. The basic element of this biosensor is organophosphorus hydrolase immobilized on a nylon membrane and attached to the common end of a bifurcated optical fiber bundle. The enzyme catalyzes the hydrolysis of organophosphate compounds to form stoichiometric amounts of chromophoric products that absorb light at specific wavelengths. The back‐scattered radiation of the specific incident radiation was measured using a photomultiplier detector and correlated to the organophosphate concentration. The effects of buffer pH, temperature, and the units of enzyme immobilized on the steady‐state and kinetic response of the biosensor were investigated to optimize the operating conditions for the fiber‐optic enzyme biosensor. These conditions were then used to measure parathion, paraoxon, and coumaphos selectively without interference from carbamates and triazines. Concentrations as low as 2 μM can be measured in less than 2 min using the kinetic response. When stored in buffer at 4 °C the biosensor shows long‐term stability.

[1]  K. Lai,et al.  Bimetallic binding motifs in organophosphorus hydrolase are important for catalysis and structural organization. , 1994, The Journal of biological chemistry.

[2]  A Mulchandani,et al.  Biosensor for direct determination of organophosphate nerve agents using recombinant Escherichia coli with surface-expressed organophosphorus hydrolase. 1. Potentiometric microbial electrode. , 1998, Analytical chemistry.

[3]  Jean-Louis Marty,et al.  Biosensor for detection of organophosphate and carbamate insecticides , 1992 .

[4]  D. Munnecke,et al.  Enzymic detoxification of waste organophosphate pesticides , 1980 .

[5]  W. Rudolf Seitz Handbook of chemical and biological sensors , 1997 .

[6]  J. Grimsley,et al.  Dramatically stabilized phosphotriesterase-polymers for nerve agent degradation. , 1997, Biotechnology and bioengineering.

[7]  S. Harvey,et al.  Rational Enzyme Design: Computer Modeling and Site-directed Mutagenesis for the Modification of Catalytic Specificity in Organophosphorus Hydrolase , 1996, CHIMIA.

[8]  A Mulchandani,et al.  Biosensor for direct determination of organophosphate nerve agents. 1. Potentiometric enzyme electrode. , 1999, Biosensors & bioelectronics.

[9]  J. Wild,et al.  The development of a new biosensor based on recombinant E. coli for the direct detection of organophosphorus neurotoxins. , 1996, Biosensors & bioelectronics.

[10]  B. Pogell,et al.  Purification and characterization of a secreted recombinant phosphotriesterase (parathion hydrolase) from Streptomyces lividans , 1991, Applied and environmental microbiology.

[11]  R Narayanaswamy,et al.  Fibre-optic pesticide biosensor based on covalently immobilized acetylcholinesterase and thymol blue. , 1997, Talanta: The International Journal of Pure and Applied Analytical Chemistry.

[12]  M. A. Connor,et al.  Genetic Engineering Approach to Toxic Waste Management: Case Study for Organophosphate Waste Treatment , 1990, Biotechnology progress.

[13]  F. Raushel,et al.  Detoxification of organophosphate pesticides using an immobilized phosphotriesterase from Pseudomonas diminuta , 1991, Biotechnology and bioengineering.

[14]  V. E. Lewis,et al.  Structure-activity relationships in the hydrolysis of substrates by the phosphotriesterase from Pseudomonas diminuta. , 1989, Biochemistry.

[15]  G. Payne,et al.  Enzymatic Approach to Waste Minimization in a Cattle Dipping Operation: Economic Analysis , 1996 .

[16]  F. Raushel,et al.  Diisopropylfluorophosphate hydrolysis by a phosphotriesterase from Pseudomonas diminuta , 1989 .

[17]  A. A. Shul'ga,et al.  Conductometric biosensor for determination of organophosphorus pesticides , 1994 .

[18]  V. E. Lewis,et al.  Mechanism and stereochemical course at phosphorus of the reaction catalyzed by a bacterial phosphotriesterase. , 1988, Biochemistry.

[19]  Otto S. Wolfbeis,et al.  Fiber-optic remote detection of pesticides and related inhibitors of the enzyme acetylcholine esterase☆ , 1993 .

[20]  W. T. Beaudry,et al.  Enzymatic Hydrolysis of the Chemical Warfare Agent VX and its Neurotoxic Analogues by Organophosphorus Hydrolase , 1997 .

[21]  V. Rastogi,et al.  Enzymatic hydrolysis of Russian-VX by organophosphorus hydrolase. , 1997, Biochemical and biophysical research communications.

[22]  Félix Pariente,et al.  Determination of organophosphorus and carbamic pesticides with an acetylcholinesterase amperometric biosensor using 4-aminophenyl acetate as substrate , 1994 .

[23]  Ashok Mulchandani,et al.  A Potentiometric Microbial Biosensor for Direct Determination of Organophosphate Nerve Agents , 1998 .

[24]  F. Raushel,et al.  Purification and properties of the phosphotriesterase from Pseudomonas diminuta. , 1989, The Journal of biological chemistry.

[25]  W. Mulbry,et al.  Biodegradation of the Organophosphate Insecticide Coumaphos in Highly Contaminated Soils and in Liquid Wastes , 1996 .