Capteur biomimétique à base de polymère à empreinte moléculaire pour la détection impédimétrique de la testostérone
Résumé
A biomimetic sensor based on acrylate moleculary imprinted polymer was designed for testosterone impedimetric detection. The sensor was prepared by grafting the 2,2’-Azobis(2-amidinopropane) azo-initiator (APA) on a gold electrode modified by a mixed alkanethiol self-assembled monolayer (SAM). The different steps of electrode modification were characterized by cyclic voltammetry and impedimetry. The initiator-electrode distance was varied by changing the mercaptoacid chain length. We showed that APA binding results in a decrease of the charge transfer resistance through the SAM layer.The maximal transfer was observed using an equimolar proportion of 1-hexanethiol and 11-mercaptoundecanoic acid. In those conditions, a MIP film was synthetized at the transducer surface using UV light in the prescence of methacrylic acid as functionnal monomer, ethyleneglycol dimethacrylate as crossliker and testosterone as template. Using this sensor, we were able to detect testosterone by impedimetry in the 1- 500ng/L range.