Resumen de Immunosensor based on ink printed electrode for staphylococcal enterotoxin detection
Maria Gardenny Ribeiro Pimenta-Martins, Roselayne Ferro Furtado, Rosa Fireman Dutra, Luiz Guilherme Dias Heneine, Ricardo Souza DIAS, Maria de Fatima Borges, Carlucio Roberto Alves
Staphylococcal enterotoxin is one of the more aggressive enterotoxins produced by Staphylococcus aureus strains and it is a common cause of food poisoning. Analytical methods that are sensitive, low cost and easy to use are needed to evaluate the food quality. This work describes the development of a label free immunosensor based on screen-printed AuNPs/carbon and the characterization of its analytical response for staphylococcal enterotoxin B (SEB) detection. The biosensor was constructed from self-assembled monolayer of thiols and protein A for the oriented immobilization of the polyclonal antibodies against SEB. As electrons mediator, potassium ferrocyanide was used. The electrochemical detection was direct with the parameters following: -0.2 to 0.6 V with the pulse amplitude of 0.075 V and the pulse width of 75 ms. The immunosensor showed detection and quantification limits of 0.4 µg mL-1 and 1.6 µg mL-1,respectively. The immunosensor showed quite satisfactory performance in contaminated and non-contaminated cheese samples.
