Assessment of Organophosphate and Carbamate Pesticide Residues in Cigarette Tobacco with a Novel Cell Biosensor

Abstract

Abstract:The conventional analysis of pesticide residues in analytical commodities, such as tobacco and tobacco products is a labor intensive procedure, since it is necessary to cover a wide range of different chemicals, using a single procedure. Standard analysis methods include extensive sample pretreatment (with solvent extraction and partitioning phases) and determination by GC and HPLC to achieve the necessary selectivity and sensitivity for the different classes of compounds under detection. As a consequence, current methods of analysis provide a limited sample capacity. In the present study, we report on the development of a novel cell biosensor for detecting organophosphate and carbamate pesticide residues in tobacco. The sensor is based on neuroblastoma N2a cells and the measurement of changes of the cell membrane potential, according to the working principle of the Bioelectric Recognition Assay (BERA). The presence of pesticide residues is detected by the degree of inhibition of acetylcholine esterase (AChE). The sensor instantly responded to both the organophoshate pesticide chlorpyriphos and the carbamate carbaryl in a concentration-dependent pattern, being able to detect one part per billion (1 ppb). Additionally, tobacco leaf samples (in blended dry form) were analyzed with both the novel biosensor and conventional methods, according to a double-blind protocol. Pesticide Sensors 2008, 8 2819 residues in tobacco samples caused a considerable cell membrane hyperpolarization to neuroblastoma cells immobilized in the sensor, as indicated by the increase of the negative sensor potential, which was clearly distinguishable from the sensor's response against pesticide-free control samples. The observed response was quite reproducible, with an average variation of +5,6%. Fluorescence microscopy observations showed that treatment of the cells with either chlorpyrifos or carbaryl was associated with increased [Ca 2+ ]cyt .The novel biosensor offers fresh perspectives for ultra-rapid, sensitive and low-cost monitoring of pesticide residues in tobacco as well as other food and agricultural commodities.

Mercaptobenzothiazole-on-Gold Organic Phase Biosensor Systems: 3. Thick-Film Biosensors for Organophosphate and Carbamate Pesticide Determination

“…Biosensors have filled the gap in this regard and these analytical devices are based on the intimate contact between a bio-recognition element that interacts with the analyte of interest and a transducer element that converts the bio-recognition event into a measurable signal. Among the different types of biosensors, the electrochemical sensors are of special interest due to the high sensitivity inherent to the electrochemical detection and the possibility to miniaturise the required instrumentation, thereby making the construction of compact and portable analysis devices possible (Campàs et al, 2009;Mavrikou et al, 2008). In this paper, we describe the application of a mercaptobenzothiazole-on-gold biosensor system for the analysis of OP and CM pesticide compounds.…”

“…However, as with the overuse of many pesticides, the OP and CM compounds leave residues in the soil, crops and surface water, which in turn exert a great threat to the environment and human health. The OP and CM compounds enter organisms and then inhibit the activity of acetyl cholinesterase (AChE) by irreversibly binding to the active site of this enzyme, which is important for the transmission of nerve impulses (Wu et al, 2009;Somerset et al, 2009;García de Llasera et al, 2009;Mavrikou et al, 2008;Liu et al, 2008;Boon et al, 2008;Pinheiro & De Andrade, 2009). A broad range of adverse effects can result from AChE inhibition and it includes abdominal pain and cramps, glandular secretions, skeletal muscle twitching, flaccid paralysis, tiredness, nausea, blurred vision, drowsiness, eye pain, convulsions, respiratory failure and untimely death.…”

“…Due to the increasing toxicity and adverse effects of pesticides, many countries are now monitoring environmental and food samples for pesticides and have established maximum residue levels (MRLs) for various pesticides in food products (Hildebrandt et al, 2008). Some of the conventional methods used for chemical analysis of pesticides include spectrophotometry, infrared spectrometry, flow-injection chemiluminescence, fluorimetry, fluorescence spectrometry, mass spectrometry, but mainly chromatographic techniques, such as gas chromatography-mass spectrometry (GC-MS) and high-performance liquid Intelligent and Biosensors 186 chromatography (HPLC) (Wu et al, 2009;García de Llasera et al, 2009;Mavrikou et al, 2008;Liu et al, 2008;Caetano & Machado, 2008). There is no doubt that these methods are highly efficient and allow discrimination among different types of OP and CM compounds, but they require tedious sample pre-treatments, highly qualified technicians and sophisticated instruments.…”

Cellular bioelectric profiling: a novel method to differentially assess the in vitro toxicity of pesticides

“…Flampouri et al [14] developed a potentiometric BERA biosensor system based on immobilized N2a and Vero cells for the sensitive (limit of detection = 3 nM), qualitative and, in some concentrations, quantitative detection of the organophosphate insecticide diazinon and the dithiocarbamate fungicide propineb in tomato samples. Using a similar approach, Mavrikou et al [10] were able to detect the organophoshate pesticide chlorpyriphos and the carbamate carbaryl in tobacco in a concentration-dependent pattern, down to a concentration of one part per billion (1 ppb). Lokka et al [31] successfully applied the same potentiometric working principle to two different cell types (neuroblastoma and tobacco protoplasts) for detecting a mixture of two organophosphate pesticides, diazinon and chlorpyrifos in two different substrates (tomato, orange).…”

“…Bioelectric assay methods based on mammalian cells have gained considerably in popularity over the past few years. Model approaches are represented by the measurement of (1) extracellular recordings from cardiac myocytes cultured on microelectrode arrays (MEA) [6], (2) the impedance of adherent cells in culture [7,8] and (3) membrane potential of cells immobilized in a gel matrix (the Bioelectric Recognition Assay -BERA) [9,10]. In the present report we describe a new approach for the simple, rapid and cost-efficient measurement of bioelectric patterns of different mammalian cell lines in response to toxicants belonging to different chemical groups.…”