Optimization of different methods and strategies for the regeneration of an electrochemical Immunosensor

YANINA PUERTAS; BARRAZA, DANIELA; MADRID, ROSSANA E.

Piriápolis

Congreso; XXII Congreso Argentino de Bioingeniería (SABI 2020); 2020

This work aims to optimize thefunctionalized antigen-antibody detection system in a biosensor to detecttransgenic plants by using the pure NPTII protein (neomycin phosphotransferaseII) as an antigen, which was purified by the group of the ITANOA (CONICET) andthe Agroindustrial Experimental Station ?Obispo Colombres? (EEAOC) of Tucumán.The optimization was made onbiofunctionalized gold electrodes for the immobilization of the specificantibodies, considering this decisive stage in terms of specificity,sensitivity, reproducibility, and stability of the immunosensor. Theelectrochemical response of this affinity biosensor was characterized, anddifferent strategies were evaluated for its regeneration and re-use in thelaboratory. To achieve this regeneration, it was necessary to separate theantigen from the antibody after the reaction, to allow the biosensor to beavailable again for a new detection. This dissociation has as a crucialrequirement, to retain the maximum activity and specificity of the immobilizedantibodies and / or antigens after separation.Adequate immobilization was achieved bythe cross-linking method (PEI-GA), and it was possible to dissociate theantigens form the immobilized antibodies (Anti NPTII). To achieve this, it wasused the dissociation agent composed by a mixture of glycine, hydrochloric acidand dimethyl sulfoxide at pH: 2.3, which allowed the correct regeneration ofthe biosensor.