Chiral discrimination of amino acids in meteorite and desert soil extracts via single-molecule nanogap conductance.

Single-molecule electrical measurements can distinguish and quantify L- and D-amino acids with over 80% accuracy, enabling detection of enantiomeric excess in complex samples.

• Why it matters: Identifying enantiomeric excess is crucial for detecting potential biosignatures beyond Earth, but current methods lack robustness and sensitivity at low concentrations in complex mixtures.
• What they did: The study employed quantum tunneling current measurements to analyze individual amino acids, testing 39 samples and mixtures, including meteorite and desert soil extracts, with targeted panels of 11 amino acids.
• The result: This approach accurately identifies molecular chirality and composition, capturing key features of complex samples and laying the groundwork for advanced astrobiological and biochemical analyses.