Gold nanogap sensor reads amino acid chirality for life detection

Researchers at Osaka University built a solid-state quantum tunneling sensor: two atomically sharp gold wires sit 0.56–0.58 nm apart, and at 0.1 V a single amino acid molecule alters the tunneling current. A machine learning classifier distinguished L- and D-forms with roughly 87.6% accuracy.

• Gap between gold nanowires is 0.56–0.58 nm at 0.1 V
• L- and D-form discrimination accuracy is about 87.6%
• Sensor withstands up to 300 °C and needs no active cooling
• Tested against LC-MS on Atacama soil and Murchison meteorite samples