There are several parameters to consider for optimization of binding-induced electrochemical signal gain. The aptamer probe packing density, the nature of the self-assembling monolayer, and the ACV frequency are factors that affect detecting and measuring of signal.  Two main factors are considered when fabricating the packing density on the probe surface. The concentration of aptamer and the surface chemistry of the self-assembling monolayer (SAM) enable variations of desired probe packing density.