Immobilization of Penaeus merguiensis alkaline phosphatase on gold nanorods for heavy metal detection.
Biotechnology of enzyme has gained popularity due to the growing need for novel environmental technologies and the development of innovative mass-production. The work describes the original application of biosensors based on Penaeus merguiensis alkaline phosphatase (PM ALP) immobilized on gold nanorods (GNRs) to heavy metal determination. Penaeus merguiensis alkaline phosphatase (PM ALP) was immobilized on gold nanorods (GNRs) by ionic exchange and hydrophobic interactions. The optimum pH and temperature for maximum enzyme activity for the immobilized PM ALP are identified to be 11.0 and 60°C, respectively, for the hydrolysis of para-Nitrophenylphosphate (p-NPP). The kinetic studies confirm the Michaelis-Menten behavior and suggests overall slightly decrease in the performance of the immobilized enzyme with reference to the free enzyme. Kmand Vmaxvalues were 0.32µm and 54µm. min-1for free and 0.39µm and 48µmmin-1for immobilized enzymes, respectively. Similarly, the thermal stability, storage stability and stability at extreme pH of the enzyme is found to increase after the immobilization. The inhibitory effect heavy metal ions was studied on free and immobilized PM ALP. The bi-enzymatic biosensor were tested to study the influence of heavy metal ions and pesticides on the corresponding enzyme. The obtained high stability and lower decrease in catalytic efficiency suggested the great potential and feasibility of immobilized PM ALP nanobiocatalyst in efficient and apply the biosensor in total toxic metal content determination.
Department of Biochemistry, Faculty of Science, University of Hormozgan, P. O. Box 3995, Bandar Abbas, Iran. Electronic address: a.homaei@hormozgan.ac.ir.
Ahmad
A
Homaei
D000469:Alkaline Phosphatase / Q000378:metabolism*; D000818:Animals; D015374:Biosensing Techniques; D002384:Catalysis; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism; D006046:Gold; D000075322:Heavy Metal Poisoning; D006868:Hydrolysis; D057927:Hydrophobic and Hydrophilic Interactions; D007477:Ions; D019216:Metals, Heavy / Q000032:analysis*; D043942:Nanotubes; D033561:Penaeidae / Q000201:enzymology* / Q000378:metabolism; D010575:Pesticides / Q000737:chemistry; D011041:Poisoning / Q000201:enzymology; D013696:Temperature
D004800:Enzymes, Immobilized; D007477:Ions; D019216:Metals, Heavy; D010575:Pesticides; D006046:Gold; D000469:Alkaline Phosphatase
Biosensor; Gold nanorods; Heavy-metal ions; Immobilization; PM ALP