Optical pico-biosensing of lead using plasmonic gold nanoparticles and a cationic peptide-based aptasensor.

A novel biosensor for the rapid detection of lead ions employing the optical properties of AuNPs, a lead-specific aptamer and a cationic peptide has been demonstrated. The limit of detection of the biosensor was 98.7 pM, the lowest so far obtained using colorimetry.