Fluorescent Probes: Well‐Defined Nanoclusters as Fluorescent Nanosensors: A Case Study on Au₂₅(SG)₁₈ (Small 13/2012)

Due to the polydispersity of nanocrystals and their unknown structures, in many cases it is difficult to conduct in-depth investigation on the sensing mechanism when nanocrystals are used as fluorescent probes; however, their smaller counterparts–structurally well-defined gold nanoclusters as sensors–have provided opportunities to do so. Herein, an example is provided by Wu et al. The potential of glutathione-capped Au25 nanocluster as silver-ion sensor is evaluated; more importantly, three factors are revealed to be responsible for the unique fluorescence enhancement of Au25(SG)18 illuminated in the image. This work is dedicated to the 30th anniversary of the Institute of Solid Physics, CAS.