Arginine-engineered gold nanoclusters for doxorubicin chemiluminescence sensing

Abstract The limited chemiluminescence (CL) emission intensity and efficiency of some traditional CL systems have restricted their application in practical analytical detection. Strategies such as catalysis and CL resonance energy transfer (CRET) are frequently employed to enhance CL performance. In this work, we synthesized arginine surface-engineered 6-aza-2-thiothymine gold nanoclusters (Arg/ATT-AuNCs) via host-guest assembly, which exhibit exceptional catalytic activity and intense photoluminescence. Arg/ATT-AuNCs amplified the CL intensity from NaIO 4 -H 2 O 2 system by 1200-fold. The CL Mechanistic studies revealed that Arg/ATT-AuNCs not only accelerated decay of H 2 O 2 to form reactive oxygen species, but also acted as efficient energy acceptors of singlet oxygen (¹O₂) via a CRET pathway. It was observed that doxorubicin (DOX) quenches the enhanced CL signal through an internal filtering effect that disrupts the CRET process. Based on this, a straightforward, rapid, and highly sensitive biosensor has been developed for the detection of DOX in human serum samples, achieving a low detection limit of 0.029 µM. The biosensor was applied to DOX determination in human serum samples with recoveries ranging from 91.1 to 106.2%. This study not only provides a new method for the detection of DOX, but also broadens the application scope of AuNCs in the field of CL.