Electrophoretically encapsulated gold nanoclusters within a silica isoporous membrane for achieving...

Electrochemiluminescence (ECL) has emerged as an important analytical method, but the scarcity of effective emitters significantly hinders its broader application. In this work, an amine-rich silica isoporous membrane (A-SIM) was fabricated on an indium tin oxide (ITO) electrode based on a modified Stöber-solution growth approach using an anionic template. Subsequently, the negatively-charged gold nanoclusters (AuNCs) were electrophoretically encapsulated within the positively-charged nanochannels of A-SIM, resulting in a robust aggregation-induced ECL (AIECL) platform of AuNCs@A-SIM/ITO. When compared to other configurations, such as homogeneous dispersion, drop-casting on the electrode, and encapsulation within unmodified SIM, the aggregated AuNCs encapsulated within A-SIM exhibited a remarkable AIECL effect, achieving an ECL efficiency of 17.89%. In contrast, the presence of cyanide ions (CN^-) leads to the specific etching of AuNCs, resulting in a diminished AIECL intensity, which enables the highly sensitive and selective detection of CN^-. Practical results demonstrate that the AuNCs@A-SIM/ITO platform is sensitive and reliably stable in its ECL responses, attributing to the nanochannel-confined AIECL mechanism as well as the anti-fouling properties of SIM. This research not only offers a practical approach for achieving robust nanoconfined AIECL of AuNCs but also provides new insights into the AIECL mechanism, encouraging further exploration in this area.