Detection of miniscule amounts of nucleic acid is accomplished via binding of target nucleic acid to probe material, composed of nucleic acid, which is bound to a sensor configured to sense mass. The sensor is prepared by immobilizing a probe material to a surface of the sensor, wherein the probe material is known to bind to the target nucleic acid. The prepared sensor is exposed to the target nucleic acid. The target nucleic acid binds to the probe material. The mass accumulated on the sensor reflects the amount of target nucleic acid bound to the probe material.