Electrochemical strategies for detection of diazinon

Diazinon (DZN) was first registered as an insecticide in the U.S. However, it was categorized in the limited group of pesticides due to its high toxicity for birds, aquatic animals, and humans. Like other organophosphorus pesticides, this compound exhibits inhibitory effects on the acetylcholinesterase enzyme. The inhibition of the enzyme leads to the accumulation of acetylcholine and causes the death of insects. DZN is considered a toxic compound for humans due to its high adsorption via skin and inhalation, which leads to the emergence of different symptoms of toxicity. When DZN is used for plants, the compound residues in crops enter the food chain bringing about different health problems. Moreover, the compound is easily washed by surface water and enters the groundwater. Its entrance into aquatic envi­ronments can negatively affect a wide range of non-targeted organisms. Thus, rese­archers seek to find fast and precise methods for the analysis of DZN. The electro­chemical method for recognizing the compound in real samples is preferable to other analytical methods. Because this method can be used without spending time preparing the sample, it is simple, fast, and cost-effective. Since such determinations may be made by using electro­chemical sensors and biosensors, numerous researchers have developed such sensors for DZN detection, and different sensitive materials were used in order to improve the selecti­vity, sensitivity, and detection limit. The present study aims to present the main progress and performance characteristics of electrochemical sensors and biosensors used to detect DZN, as it is reported in a number of relevant scientific papers published mainly in the last decade

Enzyme-Based Biosensors for Electrochemical Detection of Pesticides–A Mini Review

Despite their important contribution in increasing crops production, most pesticides are harmful to humans and living beings and can persist in the environment over long a long duration. Traditional chromatographic methods of analysis are expensive and cumbersome. Biosensor technology appears therefore as an efficient and economical alternative for fast detection of pesticides. The devices are portable, rapid, and highly sensitive. Other important features of the devices are their relatively high sensistivity and low response time. Enzymatic biosensors for pesticide detection rely either on the inhibition mechanism or on the catalytic activity of the immobilized enzyme toward a specific pesticide. Metal and carbon based nanomaterials are being widely used as immobilization support owing to novel characteristics such as biocompatibility and enhanced electron transfer ability for sensitive electrochemical detection, among others. This review focusses on the electrochemical detection of organophosphorus pesticides, delineating the limit of detection and response time of biosensors toward a wide range of organophosphorus pesticides

Elektrokemijski biosenzori za procjenu onečišćivača radi poboljšanja kakvoće hrane

This paper describes the application of electrochemical disposable biosensors in food analysis, which have recently been developed in our laboratory. The disposable biosensors, based on acetylcholinesterase inhibition potential, were exploited for testing the presence of organophosphorus and carbamatepesticides in water, fruit, and vegetable samples. The paper further describes preliminary tests for the detection of genetically modified organisms and hybridisation by coupling the DNA biosensors with the polymerase chain reaction.U radu su opisane neke primjene jednokratnih elektrokemijskih biosenzora za analizu hrane koji su nedavno razvijeni u našem laboratoriju. Biosenzori za jednokratnu upotrebu, bazirani na inhibiciji aktivnosti kolinesteraze primijenjeni su za ispitivanje prisutnosti organofosfornih i karbamatnih pesticida u uzorcima voda, voća i povrća. Razvijena je skupina DNK-biosenzora, a u ovom radu prikazani su rezultati preliminarnih ispitivanja detekcije genetički modificiranih organizama i hibridizacije vezanjem PCR i DNK-biosenzora

Electrochemical Biosensors Containing Pure Enzymes or Crude Extracts as Enzyme Sources for Pesticides and Phenolic Compounds with Pharmacological Property Detection and Quantification

Biosensors are chemical sensors in which the recognition system is based on a biochemical mechanism. They perform the specific component detection in a sample through an appropriate analytical signal. Enzyme-based biosensors are the most prominent biosensors because of their high specificity and selectivity; besides being an alternative to the common immunosensors, they are more expensive and present a limited binding capacity with the antigen depending on assay conditions. This chapter approaches the use of enzymes modified electrodes in amperometric biosensing application to detect and quantify pesticides and phenolic compounds with pharmacological properties, as they have been a promising analytical tool in environmental monitoring. These biosensors may be prepared from pure enzymes or their crude extracts. Pure enzyme-based biosensors present advantages as higher substrate specificity and selectivity when compared to crude extract enzymatic biosensors; nevertheless, the enzyme high costs are their drawbacks. Enzymatic crude extract biosensors show lower specificity due to the fact that they may contain more than one type of enzyme, but they may be obtained from low-cost fabrication methods. In addition, they can contain enzyme cofactors besides using the enzyme in its natural conformation

Piezoelectric biosensors for organophosphate and carbamate pesticides: a review

Due to the great amount of pesticides currently being used, there is an increased interest for developing biosensors for their detection. Among all the physical transducers, piezoelectric systems have emerged as the most attractive due to their simplicity, low instrumentation costs, possibility for real-time and label-free detection and generally high sensitivity. This paper presents an overview of biosensors based on the quartz crystal microbalance, which have been reported in the literature for organophosphate and carbamate pesticide analysis