A label-free thrombin binding aptamer as a probe for highly sensitive and selective detection of lead(II) ions by a resonance Rayleigh scattering method.

The binding of lead(II) ions with unusually high affinity to a thrombin binding aptamer resulted in an enhancement of resonance Rayleigh scattering (RRS). A simple, sensitive, and selective assay for the direct determination of trace amounts of Pb(2+) on the basis of RRS has been proposed.