An inkjet printed Ag electrode fabricated on plastic substrate with a chemical sintering approach for the electrochemical sensing of hydrogen peroxide

The trend of developing electrochemical sensors toward cellular level detection put forward higher requirements of the electrodes in the detection performance. However, common disk electrodes or conventional screen printing electrodes meet up with some limitations in the electrocatalytic activity and electron transfer capability. In this work, we applied inkjet printing technology to fabricate electrodes to make some improvements. Highly conductive Ag nanoparticles based electrodes were obtained on plastic substrate by inkjet printing technology followed by a sintering process at room temperature. The resistivity of IPAgE is determined to be 64.0 ± 5.3 μΩ cm. With better conductivity and the nanoparticle-based interface, superb electrochemical response of IPAgE for H₂O₂ was obtained, nearly 300-fold higher than the conventional screen printed Ag electrode. Moreover, high sensitivity of 287 μA mM⁻¹ cm⁻² with a LOD of 5.0 μM was obtained under the optimized 20 printed layers. The inkjet printed Ag electrodes were also credibly applied in the detection of H₂O₂ release from living cells. This work demonstrates inkjet printing is a promising method for the high performance electrochemical sensors.