Blue-emitting tryptophan-protected gold nanoclusters acted as a sensitive nanosensor for fluorescence sensing and visual imaging detection of furaltadone.

Herein, blue-emitting gold nanoclusters (Au NCs) were carried out through tryptophan as the protecting and reducing agents. In aqueous solution of Au NCs@tryptophan, the addition of furaltadone guaranteed the interaction of furaltadone with tryptophan around Au NCs. The propinquity of furaltadone to Au NCs caused that the fluorescence of Au NCs was weakened by furaltadone based on the inner filter effect (IFE). Under the optimal measurement conditions, the logarithm of relative fluorescence intensity of Au NCs@tryptophan was linearly carried out with the furaltadone amount increasing from 0.5 to 100 μM, the corresponding detection limit was 0.087 μM. The fluorescence change of Au NCs@tryptophan displayed excellent selectivity and sensitivity for furaltadone than other possible substance in the human body. In view of Au NCs@tryptophan, the as-performed fluorescence nanosensor suggested outstanding ability for furaltadone sensing in real samples. Obviously, this nanoprobe of furaltadone could implement the naked-eye visual fluorescence determination of furaltadone.