Fluorescent DNA-templated silver nanoclusters for highly sensitive detection of D-penicillamine.

Herein, fluorescent DNA-templated silver nanoclusters (DNA-AgNCs) with red emission were synthesized and utilized as novel probe to detect D-penicillamine (D-Pen) for the first time. D-Pen molecules contain a thiol which can combine with Ag to form a non-fluorescent ground state complex, inducing the aggregation of DNA-AgNCs followed by the fluorescence quenching. The quenching mechanism is well-studied and found to be a static quenching process. This method can detect D-Pen in the range of 0.025-0.7 μM with the detection limit as low as 8 nM, which is 1-3 orders of magnitude more sensitive than those based on other fluorescent nanoprobes. More importantly, the preparation procedure for DNA-AgNCs is fast and without the requirement of heavy metal ions. Thus, this detection strategy is time-saving and eco-friendly. Satisfactory recoveries have been acquired for monitoring D-Pen in human serum samples and pharmaceutical samples owing to the high sensitivity.