Encapsulation of aggregated gold nanoclusters in a metal–organic framework for real-time monitoring of drug release

Gold nanoclusters (AuNCs), which have stable luminescence and negligible biotoxicity, are a promising candidate in biological fields. However, their low photoluminescence (PL) efficiency is unsatisfactory. Herein, aggregated gold nanoclusters (aAuNCs) were confined in a metal–organic framework (MOF) to maintain their aggregation, restrict the rotation of their ligands, and further improve their quantum yield (QY) to 7.74%. The aAuNCs-MOF exhibited high luminescence and good biocompatibility. More importantly, in addition to its pH-dependent luminescence and external porosity, the complex was applied for the first time in real-time monitoring of drug release.