Fast Detection of Chloramphenicol in Raw Milk Using a Hairpin Aptamer-templated Silver Nanoclusters

In this presented work, a facile and efficient method was established for the detection of chloramphenicol (CAP) based on target-induced structure transformation of aptamer. This aptamer DNA with a hairpin structure can coincidentally serve as a template for the synthesis of bright silver nanoclusters (quantum yield 16.36%). The binding of CAP with aptamer DNA could cause the destruction of the hairpin structure, resulting in the quenching of the fluorescence of silver nanoclusters (AgNCs). It costs less than 10 minutes to complete the assay, and excellent sensitivity was achieved with detection limit of 0.052 nmol/L. The selectivity and recovery experiments also demonstrated satisfactory results of this proposed protocol. The method has potential applicability, and provides a new strategy for the development of label-free sensors based on aptamer and AgNCs.