Site‐specific fabrication of gold nanocluster‐based fluorescence photoswitch enabled by the dual roles of albumin proteins

Fluorescence photoswitch is becoming increasingly desirable for many applications, but its controllable fabrication still remains challenging yet. In this paper, a new strategy proposed to fabricate fluorescence by harnessing dual roles of albumin proteins as both photochrome carriers and biotemplates fluorophore. As an example, we demonstrated the successful incorporating photochromic diarylethene dye (CMTE) red-emitting fluorescent gold nanoclusters (AuNCs) into specific domains bovine serum (BSA) in highly manner. Detailed spectral photophysical characterisation showed that CMTE well-retains properties within CMTE–BSA–AuNC construct, although photoconversion rate slightly retarded. Different from previously reported photoswitches, present system mainly modulated via inner filter effect (IFE) mechanism, which exhibits high switching efficiency with on–off ratio up 90%, reversible response good antifatigue performance. This work provides new, generable protein-assisted fabricating advanced photoswitch, can find wide applications biological, optical information fields.