High-sensitivity nanoscale wire sensors

A method, comprising:

• providing a field effect transistor comprising a source electrode, a global gate electrode, a drain electrode, and a semiconductor nanoscale wire having a reaction entity immobilized relative thereto connecting the source electrode and the drain electrode, wherein the nanoscale wire is exposed to a solution;
• and
• applying voltage to the global gate electrode such that the semiconductor nanowire exhibits a carrier density of less than about 1019 cm−3.

A method, comprising:

• exposing a semiconductor nanoscale wire, having a reaction entity immobilized relative thereto, to a solution suspected of containing an analyte that the reaction entity is able to bind, wherein the nanoscale wire has a Debye screening length in the solution that is greater than the average cross-sectional dimension of the nanoscale wire when the analyte is bound to the reaction entity.