To further illustrate the strong temperature dependance of monolayer degradation, we repeated the same electrochemical aptamer sensor testing with MCH and MCO passivation layers in buffer conditions at a low temperature of 4 °C, which based on the Arrhenius equation should theoretically result in monolayer desorption rates ~10 6 times slower than those at 37 °C. Figure shows the voltammogram results of MCH and MCO fabricated sensors repeatedly scanned for 7 days at 4 °C in PBS. Repeated scanning still resulted in significant loss of redox tag current as expected and previously reported, where excessive scanning is suspected to desorb the monolayer over time. However, MCH sensors lost >50% less current at 4 °C than at 37 °C and voltammograms show oxygen reduction increased only slightly over 7 days (Figure ), indicating that the passivating monolayer was well-preserved at this temperature. Surprisingly, at 4 °C MCH and MCO sensors lost similar amounts of redox tag current (~45%), suggesting that these losses were largely due to electric-field induced desorption of aptamer upon repeated scanning since thermal desorption of the monolayer at this temperature should be negligible.