Excessive diazinon residue in vegetables can endanger human health. Therefore, a simple, fast, and accurate method is needed to detect residue. A conductometric biosensor is a good choice because it also offers high selectivity and sensitivity. The principle of detection of the conductometric biosensor is based on enzymatic hydrolysis of diazinon into O,O diethyl phosphorothiate,2-isopropyl-6-methylpyrimidin-4-ol, and H+ catalyzed by organophosphate hydrolase (OPH). The optimum amount of organophosphate hydrolase added to the screen-printed carbon electrode (SPCE) modified with BSA-glutaraldehyde is 118.5 µg, while the optimum pH is 8.5. This biosensor has a response time of 30 sec, a linear dynamic range of 0 to 1 ppm, sensitivity of 42.21 µS/ppm, and limit of detection of 0.19 ppm.
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Prayoga, Indrajid; Mulyasuryani, Ani; and Prasetyawan, Sasangka
"Construction and Characterization of Conductometric Biosensor for
Determination of the Diazinon Concentration,"
Makara Journal of Science: Vol. 8:
1, Article 12.
Available at: https://scholarhub.ui.ac.id/science/vol8/iss1/12