Use of Fe3O4 Nanoparticles for Enhancement of Biosensor Response to the Herbicide 2,4-Dichlorophenoxyacetic Acid
Open Access
- 17 September 2008
- Vol. 8 (9), 5775-5791
- https://doi.org/10.3390/s8095775
Abstract
Magnetic nanoparticles of Fe3O4 were synthesized and characterized using transmission electron microscopy and X-ray diffraction. The Fe3O4 nanoparticles were found to have an average diameter of 5.48 ±1.37 nm. An electrochemical biosensor based on immobilized alkaline phosphatase (ALP) and Fe3O4 nanoparticles was studied. The amperometric biosensor was based on the reaction of ALP with the substrate ascorbic acid 2-phosphate (AA2P). The incorporation of the Fe3O4 nanoparticles together with ALP into a sol gel/chitosan biosensor membrane has led to the enhancement of the biosensor response, with an improved linear response range to the substrate AA2P (5-120 μM) and increased sensitivity. Using the inhibition property of the ALP, the biosensor was applied to the determination of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). The use of Fe3O4 nanoparticles gives a two-fold improvement in the sensitivity towards 2,4-D, with a linear response range of 0.5-30 μgL-1. Exposure of the biosensor to other toxicants such as heavy metals demonstrated only slight interference from metals such as Hg2+, Cu2+, Ag2+ and Pb2+. The biosensor was shown to be useful for the determination of the herbicide 2, 4-D because good recovery of 95-100 percent was obtained, even though the analysis was performed in water samples with a complex matrix. Furthermore, the results from the analysis of 2,4-D in water samples using the biosensor correlated well with a HPLC method.Keywords
This publication has 31 references indexed in Scilit:
- Amperometric 2,4-Dichlorophenoxyacetate Biosensor System Based on a Microbial Reactor and a Tyrosinase-Modified ElectrodeAnalytical Letters, 2007
- Magnetic loading of carbon nanotube/nano-Fe3O4 composite for electrochemical sensingTalanta, 2006
- Highly sensitive regenerable immunosensor for label-free detection of 2,4-dichlorophenoxyacetic acid at ppb levels by using surface plasmon resonance imagingSensors and Actuators B: Chemical, 2005
- Characterization of aqueous dispersions of Fe3O4 nanoparticles and their biomedical applicationsBiomaterials, 2005
- A phenol biosensor based on immobilizing tyrosinase to modified core-shell magnetic nanoparticles supported at a carbon paste electrodeAnalytica Chimica Acta, 2004
- Free and sol–gel immobilized alkaline phosphatase-based biosensor for the determination of pesticides and inorganic compoundsAnalytica Chimica Acta, 2003
- Horseradish peroxidase sol–gel immobilized for chemiluminescence measurements of alkaline-phosphatase activitySensors and Actuators B: Chemical, 2001
- The specific immunochemical detection of 2,4-dichlorophenoxyacetic acid and 2,4,5-trichlorophenoxyacetic acid pesticides by amperometric cholinesterase biosensorsAnalytica Chimica Acta, 1997
- Development of an amperometric flow injection immunoanalysis system for the determination of the herbicide 2,4-dichlorophenoxyacetic acid in waterBiosensors and Bioelectronics, 1997
- Zeptomole-Detecting Biosensor for Alkaline Phosphatase in an Electrochemical Immunoassay for 2,4-Dichlorophenoxyacetic acidAnalytical Chemistry, 1996