OMA Protocol Review: OMAMAN-56 Sulfites in Shrimp

A biosensor is a compact analytical device that combines a biological component with a physiochemical transducer to detect analytes of interest. In the case of the BIOFISH 300, Biolan combines the high specificity and selectivity of specific enzymes for each analyte with amperometric transduction of this biological signal, easily detectable and quantifiable. The technology is based on the development of Biotest, the working electrode, which has an immobilized enzyme along with other electro active components, which bring about a change in the electrical current when put in contact with the analyte to be detected. How is the analysis performed? Biotest technology is based on a working electrode which immobilizes the enzyme together with other electroactive components. A change in the electrical current is then produced when these components come into contact with the analyte to be detected. Any of the processes performed in the Biofish-300 (activation, calibration, analysis, etc.) comprise two different parts. The first phase is when the device records the electrical signal that circulates in the electrochemical cell (establishing the target) as soon as the process begins, when the measuring cuvette is only filled with Measurement Solution. The second phase begins with the addition of the Calibration Standard or of the sample to the measuring cuvette, once the device has issued a sound signal, indicating that the target of each measurement has been established correctly. This addition increases the electrical current in the cell due to the redox reaction sequence that occurs on the Biotest surface. The device uses the difference in intensities recorded before and after the addition to calculate a current intensity variation that correlates with the sulphite concentration by means of a prior calibration of the device.

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