Two-dimensional networks of pristine single-walled carbon nanotubes (SWNTs), which cover only a small fraction of an insulating substrate (<1%), behave as macroscopic electrodes (response-dependent on the geometric area of the substrate), but with unprecedented low background currents, dependent on the area of SWNTs. This facilitates cyclic voltammetry (CV) at low concentrations (similar to nanomolar), particularly significant given that carbon is a key electrode material for bioelectrochemists.