Biomolecule detecting apparatus and biomolecule detecting method employing the same

A biomolecule detecting apparatus comprising:

• a field effect transistor:
• an electrode connected to the gate of said field effect transistor by a wire, wherein said electrode is in contact with a buffer solution into which a sample is introduced and has a probe that binds to a target in said sample immobilized on the surface thereof;
• a reference electrode that comes into contact with said buffer solution;
• a power supply connected to said reference electrode;
• and
• a detecting unit for processing an output of said field effect transistor,
• wherein the source, drain, and channel of said field effect transistor are covered with a light-shielding member.

A method for detecting a biomolecule comprising the steps of:

• bringing a buffer solution into contact with an electrode of a field effect transistor, said electrode having a probe that binds to a target in a sample immobilized on the surface thereof;
• applying an input voltage waveform across said electrode and a reference electrode that is in contact with said buffer solution;
• injecting a sample into said buffer solution;
• and
• detecting a change in response of said field effect transistor before and after the injection of said sample.