Articulo
Confined gold nanoparticles enhance the detection of small molecules in label-free impedance aptasensors
Registro en:
issn:2040-3372
Autor
Peinetti, Ana S.
Ceretti, Helena
Mizrahi, Martín Daniel
González, Graciela A.
Ramírez, Silvana A.
Requejo, Félix Gregorio
Montserrat, Javier M.
Battaglini, Fernando
Institución
Resumen
A controlled architecture of nanoelectrodes, of a similar size to small molecule-binding aptamers, is synthesized inside nanoporous alumina. Gold nanoparticles with a controlled size (about 2 nm) are electrogenerated in the alumina cavities, showing a fast electron transfer process toward ferrocyanide. These uncapped nanoparticles are easily modified with a thiol-containing aptamer for label-free detection of adenosine monophosphate by electrochemical impedance spectroscopy. Our results show that the use of a limited electrical conducting surface inside an insulating environment can be very sensitive to conformational changes, introducing a new approach to the detection of small molecules, exemplified here by the direct and selective detection of adenosine monophosphate at the nanomolar scale. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas