Electrochemical impedance spectroscopy for the study of juvenile hormones-recombinant protein interactions

The interactions of recombinant juvenile hormone binding protein (His8-rJHBP) with juvenile hormones (JHs), methoprene and farnesol have been studied with electrochemical impedance spectroscopy (EIS). The protein was immobilized on the dodecanethiol (DDT) modified gold electrodes. Each step of electrode modification has been confirmed with cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The conformation changes of His8-rJHBP upon JHs and methoprene binding have been presented. The EIS determined association constants in the JHs analogs-immobilized His8-rJHBP system indicate that lack of the epoxide moiety in methoprene molecule is not critical for observed high affinity of this compound to the binding region of the His8-rJHBP protein.