Amperometric biosensing biosensors

Some applications of amperometric biosensing strategies for pesticide detection in real or spiked food samples have been recently reported. Most of the applications have been developed for vegetable matrices. Different formats of biosensors have been used disposable screen-printed choline oxidase biosensors [23] using AChE in solution were utilized to detect pesticides in real samples of fruit and vegetables. 

In the simplest format, amperometric biosensors are constructed in such a way that in the absence of other electroactive sample components, the faradaic current produced at the electrode surface is produced solely due to presence of the product of an enzyme-catalyzed reaction as illustrated in Figure 1. Three possible configurations available for an amperometric biosensing electrode system [4] are illustrated in Figure 2 ... 

Amperometry consists in the apphcation of a fixed potential in a determined time and recording the anodic or cathodic current. Since Clark and Lyons proposed the gln-cose biosensor in 1962, amperometric biosensing has been used and can be applied for POC diagnosis. ... 

The electrochemical based biosensors are the most widely used format in biosensing. Typically the reaction under investigation would either generate a measurable current (amperometric), a measurable potential or charge accumulation (potentiometric) or measurably alter the conductive properties of a medium (conductometric) between electrodes [55]. 

Finally, some biological materials, mainly enzymes, have been introduced into carbon composite matrices and the resulting electrodes used as environmental biosensors (in addition to numerous other biosensing applications ). The main examples are based on tyrosinase (or polyphenol oxidase) for the detection of phenolic compounds or thiols, acetylcholinesterase for organophosphate and carbamate pesticides, ° ° organophosphorous hydrolase for pesticides, or bienzymatic systems for amperometric immunosensor for polycyclic aromatic hydrocarbons. ... 

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