HRP Wiring by Redox Active Layered Double Hydroxides: Application to the Mediated H₂O₂Detection

With the aim of amperometric biosensor development, enzymes were immobilized within layered double hydroxides (LDH), also called anionic clay. Synthetic redox active [Zn–Cr–ABTS] LDH is used as an immobilization matrix for HRP in order to perform the electrical wiring of the enzyme. The electrochemical transduction step corresponds to the reduction at 0.0 V of the intercalated ABTS+ ·, enzymatically formed in the presence of H2O2. The HRP/[Zn–Cr–ABTS] biosensor sensitivity and detection limit are 443 mA M−1 cm−2 and 10 nM, respectively. The co-immobilization of GOx with HPR at [Zn–Cr–ABTS] coating gives rise to a bienzymatic electrode applied to the determination of glucose at 0.0 V.