CONICET | Buscador de Institutos y Recursos Humanos

A device composed by a biological receptor and a transducer is defined as a biosensor, where a biomolecule detects a substance and the transducer, interprets and "translates" the biological recognition reaction into a quantifiable signal. Both components are responsible for biosensor sensitivity and selectivity, as well as give rise the ability of direct and real time analysis. This work proposes the design and development of an electrochemical biosensor including the enzyme horseradish peroxidase (HRP) into matrices of mineral nanoparticles (Laponita®), gold nanoparticles (AuNP) and polymers of vinylbenzyl thymine and vinylbenzyl ammonium units (VBT-VBA). Hydrogels were prepared mixing laponite and polymer with different amounts of HRP and AuNP, deposited on a glassy carbon electrode surface. The biosensor experimental variables were optimized and the analytical characteristics were determined. The analytical signal was obtained by amperometry. The stability and the functionality of the hydrogel film are influenced by a mass/charge ratio resulting in a balance between the components involved. The optimal composition of the hidrogel was: 30 μg laponite + 15 μg polymer + 15 μg HRP and 2.5 μl AuNP solution. The immobilization of the biomolecule is fundamental in the design and development of a biosensor and the laponite demonstrated optimal qualities in this sense. On the other hand, the thymine biopolymers make possible the stabilization of these structures and the AuNP improve the current signal increasing the conductivity of the hydrogel, this produce suitable microenvironments in which the biomolecules can retain their biological and biocatalytic activity. The developed biosensor showed outstanding characteristics, reason why it is potentially applicable to the analysis of real samples

enviar mensaje