Comparative Study of Nanostructured Matrices Employed in the Development of Biosensors Based on HRP Enzyme for Determination of Phenolic Compounds

Abstract

AbstractThis paper made a comparative study of new matrices of nanostructured materials (multiwall carbon nanotube, fullerene and hydroxylated fullerene) aiming to compare them when employed in the process of immobilization of enzyme horseradish peroxidase (HRP) on the development of amperometric biosensors for the determination phenolic compounds. The results confirm that all the three nanostructured matrices used in the preparation of the biosensor show improvements when acting as a transducer stabilizer and immobilization matrix, comparing to the electrode of carbon paste. Regarding the performance of these matrices it is verified that the developed biosensor employed the multiwall carbon nanotube as matrix immobilized enzyme HRP has shown the best sensitivity for the molecule of phenol (33 nA cm−2 µmol−1 L), however, regarding the range of linear response, the elaborated biosensor containing the hydroxylated fullerene has shown the best response (5–200 µmol L−1). In terms of operational stability, the biosensors maintained their responses around 95 % after more than 200 analyzes. It is also important to mention that in all the cases, the association with the graphite powder improves the answers of the biosensors around 10 to 15 %.