Horseradish peroxidase biosensor waters

Enzyme inhibition sensors are the most commonly reported enzyme-based biosensors for the detection of toxic compounds and heavy metal ions. The sensors are based on the selective inhibition of specific enzymes by classes of compounds or by the more general inhibition of enzyme activity. Most of the research carried out has been directed toward the detection of organophosphorus and carbamate insecticides and the triazine herbicides and metal ions analysis [72,73]. Several enzymes have been used in inhibition sensors for pesticides and heavy metal analysis using water, soil, and food samples including choline esterase, horseradish peroxidase, polyphenol oxidase, urease, and aldehyde dehydrogenase. 

FIGURE 11.13. Cyclic voltammogram of 4-mM DMFc on a horseradish peroxidase (HRP)/Eastman AQ 55-modified glassy carbon electrode (GCE) in acetonitrile containing 1.5% v/v water at 20 C. (A) Response of the biosensor in the absence (I) and presence (II) of 1 mM butanone peroxide (BTP). (B) Response of the biosensor to 1 mM BTP (I) and on addition of 1 mM of the inhibitor, thiourea (II). A 20 1 drop of mixed polymer-enzyme solution containing 1.4% Eastman AQ55 polymer and 0.05 mg HRP was evaporated on a 3 mm diameter GCE scan rate 5 mV s support electrolyte 0.1 M tetraethylammonium p-toluenesulphonate. 

Fig. 17 Screen-printed biosensor array used for estimation of water quality. TYR Tyrosinase, AChE Acetylcholinesterase, BChE Butyrylcholinesterase, Pt Platinum, CDH cellobiose dehydrogenase, HRP Horseradish peroxidase, GOX glucose oxidase, SBP Soybean peroxidase. Reprinted from [58], with permission from Elsevier...

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