Pesticide detection polymers

Intensive application of pesticides and polymers in agriculture and industry cause the increase of number of toxic organic substances, which circulate in an environment, and constantly complicates their disclosure, identification and quantitative detection. 

HPLC has had considerable success in separating compounds as diverse as steroids, carbohydrates, vitamins, dyestuffs, pesticides and polymers. It is used routinely for the assay of pharmaceutical products, the monitoring of drugs and metabolites in body fluids and for other biomedical, biochemical and forensic applications, such as the detection of drugs of abuse. The determination of additives in foodstuffs and beverages including sugars,... 

Ghosh, D., Dutta, K., Bhattacharyay, D. and Sarkar, P. (2006) Amperometric detection of pesticides using polymer electrodes. Environ. Monit. and Assess., 119, pp. 481-489. 

The electrochemical sensors with chemical recognition applied to pesticides analyses take advantage of the analytical features of the differential pulse voltammetry, square-wave voltammetry, and stripping voltammetry [26-30], which allow pesticides detection at residues levels. Current efforts are directed toward sensitivity and selectivity improvement by chemical modification of the electrode surface by molecularly imprinted polymers and micro- and nanostructured materials [31]. 

B. Piro, S. Reisberg, G. Anquetin, H.-T. Sue, M.-C. Pham,.Quinone-based polymers for label free reagentless electrochemical immunosensors applications to proteins, antibodies and pesticide detection. Biosensors, 3, 58-76 (2013). 

A.L. Jenkins, R. Yin, and J.L. Jensen, Molecularly imprinted polymer sensors for pesticide and insecticide detection in water. Analyst 126, 798-802 (2001). 

Figure 3.20 Pesticide in rat blood serum on vinyl alcohol polymer column. Conditions column, Asahipak GS320 (vinyl alcohol copolymer gel), 50 cm x 7.6 mm i.d. eluent, 0.05 M phosphate buffer containing 0.2 M sodium chloride pH 7.2 in 20% aqueous methanol flow rate, 1.0 ml min-1 detection, UV 254 nm. Peaks 1, blood serum protein and 2, methomyl.

Yamazaki T, Yilmaz E, Mosbach K, Sode K. Towards the use of molecularly imprinted polymers containing imidazoles and bivalent metal complexes for the detection and degradation of organophosphotriester pesticides. Anal Chim Acta 2001 435 209-214. 

Very few immunosensors are commercially available. The commercial immunosensors are either the detector or bioanalyzer types. The PZ 106 immunosensor from Universal Sensors Inc. (New Orleans, LA) has been used as a detector to measure antibody-antigen reaction. Ohmicron (Newtown, PA) developed a series of pesticide immuno-bioanalyzers that have been used in field tests. Pharmacia Biosensor USA (Piscataway, NJ) recently introduced BIAcore immunodetection system. A combination of a unique flow injection device and surface plasmon resonance (SPR) detection technique provides a real time analysis. A carboxylmethyldextran layer added to plasmon generating gold film is a hydrophobic, activatable, and flexible polymer that provides high antibody and low non-specific bindings. System demonstration at the Institute of Food Technologists (IFT) 1994 meeting in Atlanta drew attention of food scientists. It should easily be adapted for food protein characterization. 

In this section, we discuss about the screen printed electrode (SPE) based AChE sensors for the selective determination of OP and CA pesticides. In the past decades, several attempts were made by the researchers to develop SPE based pesticide sensors, where the enzyme AChE was immobilized either directly onto the electrode or above other matrices incorporated SPE surfaces. Both approaches resulted in the good, rapid detection of OP and CA pesticides. Earlier, Hart et al. employed AChE/SPE to detect OP and CA pesticides [21], They measured the enzyme activity from the rate of hydrolysis of acetylthiocholine iodide. Three polymers such as hydroxyethyl cellulose, dimethylaminoethyl methacrylate, and polyethyleneimine were used as enzyme immobilization matrices. Initially, electrodes were exposed to drops of water or pesticide solution, dried and their activity was screened after 24 h. They found that, when the enzyme matrix was hydroxyethyl cellulose, electrode activity inhibited both by water as well as by pesticides. While with co-polymer matrix, a significant response towards pesticides alone was observed. Further, the long-term storage stability of electrodes was highest when the enzyme matrix consisted of the co-polymer. The electrodes retained their activity for nearly one year. In contrast, the electrodes made of hydroxyethyl cellulose or polyethyleneimine possess less stability. 

Xenobiotics are frequently metabolized in plants by mechanisms that lead to the incorporation or inclusion of the xenobiotic into biological polymers or tissue residues that are not soluble in commonly used nonreactive solvents. These residues are frequently refered to as bound, insoluble, or nonextractable residues (2 ). Bound residues in plants have most commonly been detected in plant tissues treated with radloactlvely-labeled pesticides. These residues were an important topic of a symposium held in Vail, Colo, in 1975 (17) they have been discussed in mauiy more recent papers (11,154-1577"and they were discussed at a symposium at the l88th ACS National Meeting, 1984 "Non-extractable Pesticide Residues Characteristics, Bioavailability and Toxicological Significance". 

A capacitance-based method for specific detection of low levels of pesticides and environmental contaminants has been developed using conducting polymers... 

Mechanisms of chemical contamination in the environment has developed mainly due to the development of complex sampling methods and very sensitive techniques and instruments for chemical analysis. Without the aid of these laboratcay instruments capable of detection of very low detection limits, many examples of the environmental contamination risks would remain unveiled today. Example include problems of pesticide residuals in a water body the dioxins, furans and TCDD compounds in air originating from the incineration of solid wastes containing chlorinated polymers are all detected in ecosystems by means of such sophisticated research techniques and equipment. By... 

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