5598-15-2Relevant articles and documents
CoFe2O4@TiO2 decorated reduced graphene oxide nanocomposite for photocatalytic degradation of chlorpyrifos
Gupta, Vinod Kumar,Eren, Tanju,Atar, Necip,Yola, Mehmet Lütfi,Parlak, Cemal,Karimi-Maleh, Hassan
, p. 122 - 129 (2015)
Chlorpyrifos is widely used to control pest insects in residential, agricultural, and commercial applications. Its common use has led to the release of chlorpyrifos into sediments, wastewater and water sources. The presence of chlorpyrifos in wastewaters and water sources may affect ecosystem and human health due to its chronicle toxicity to aquatic organisms. In this study, magnetic recoverable CoFe2O4@TiO2 decorated reduced graphene oxide nanocomposite was prepared and used for investigating the photodegradation of chlorpyrifos. The nanocomposite was characterized by using transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and scanning electron microscopy. In photocatalytic degradation of chlorpyrifos experiments, the effect of operating variables such as initial chlorpyrifos concentration, catalyst dosage and contact time was also investigated. The photocatalytic degradation of chlorpyrifos followed the pseudo-first-order kinetic model. The results indicated that the nanocomposite exhibited a high efficient photocatalytic activity on the photodegradation of chlorpyrifos. The nanocomposite was separated from the solution by a magnet and reused after the photodegradation of chlorpyrifos. The recyclable of the nanocomposite is economically significant in the industry.
Oxidation of organophosphorus pesticides for the sensitive detection by a cholinesterase-based biosensor
Lee, Hye-Sung,Ah Kim, Young,Ae Cho, Young,Tae Lee, Yong
, p. 571 - 576 (2007/10/03)
A potentiometric flow injection-type biosensor developed in our laboratory was used for the determination of organophosphorus pesticides (OPs). The principle of the biosensor is that the degree of inhibition of a sensor enzyme by an OP is dependent on the concentration of the pesticide. The sensor system consisted of a reactor with acetylcholinesterase (AChE) immobilized on a controlled pore glass and a detector with a tubular H+-selective membrane electrode. In order to examine the possibility of enhancing the sensitivity of the sensor by converting OPs to oxidized forms (stronger inhibitors), a comparison of the degree of enzyme inhibition by OPs at 10-6 M before and after their oxidation was made. All of the ten pesticides tested exhibited greater inhibitory power toward the sensor enzyme following oxidation. All of the oxidized pesticides at 10-6 M inhibited the sensor enzyme to a considerable degree, demonstrating the utility of the developed method for the class-specific determination of OPs. A calibration curve for diazinon, over the concentration range of 10-11-10-4 M, was obtained. The lower detection limit was 2 × 10-10 M. Treatment of the inhibited enzyme with pyridine-2-aldoxime restored the enzyme to near full activity, allowing repeated use of the sensor,
Development of Enzyme-Linked Immunosorbent Assays for the Insecticide Chlorpyrifos. 1. Monoclonal Antibody Production and Immunoassay Design
Manclus, Juan J.,Primo, Jaime,Montoya, Angel
, p. 4052 - 4062 (2007/10/03)
The present work describes the production and characterization of monoclonal antibodies (MAbs) to the insecticide chlorpyrifos and their incorporation into several ELISA configurations. With this aim, a collection of chlorpyrifos haptens was synthesized by introducing appropriate spacers in opposite sites of the analyte molecular structure. From mice immunized with protein conjugates of these haptens, several hybridomas secreting MAbs with the ability to sensitively bind the analyte were obtained. MAbs showing the highest affinity to chlorpyrifos in homologous assays (I50 values in the 20-220 nM range) were selected. Hapten heterology involving modifications of the moiety closer to the attachment site provided the highest improvement in sensitivity. MAbs displayed striking differences in their cross-reactivity pattern with structurally related compounds. One MAb (I50 around 10 nM) was incorporated into other ELISA formats. No remarkable changes of assay characteristics, other than immunoreagent consumption and immunoassay procedure, were found. These ELISAs are potentially very valuable analytical tools for the rapid and sensitive determination of this insecticide.
