Development of an amperometric immunosensor for detection of staphylococcal enterotoxin type A in cheese

作者：Ribeiro Pimenta Martins Maria Gardenny; Furtado Roselayne Ferro; Dias Heneine Luiz Guilherme; Dias Ricardo Souza; Borges Maria de Fatima; Alves Carlucio Roberto^*

来源：Journal of Microbiological Methods, 2012, 91(1): 138-143.

DOI：10.1016/j.mimet.2012.05.016

• Food safety
• Biosensor
• Staphylococcal enterotoxin A

This paper reports a novel electrochemical immunosensor for the sensitive detection of staphylococcal enterotoxin A (SEA) based on self-assembly monolayer (SAM) and protein A immobilization on gold electrode. Three different methods of protein A immobilization were tested: physical adsorption, cross-linking using glutaraldehyde and covalent binding after activation with N-hydroxysuccinimide (NHS)/N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) on cysteamine-modified gold electrode. The EDC/NHS method for protein A immobilization was selected to lead development of the biosensor. The coating steps of the surface modification were characterized by cyclic voltammetly and the biosensor response by chronoamperometry. The advantages of the immunosensor were exposed in its high sensitivity and specificity. The proposed amperometric immunosensor was successfully used for determination of SEA in contaminated and non-contaminated cheese samples with excellent responses.

• 出版日期2012-10