A squaric acid-stimulated electrocatalytic reaction for sensing biomolecules with cycling signal amplification.
Squaric acid, a 2-dimensional planar structure of squarate C4O4 units linked by protons in a layered sheet, was utilized for the first time as a catalytic substrate for ultrasensitive electronic determination of low-abundance proteins by coupling a target-induced electrocatalytic reaction with the in situ cycling signal amplification strategy.