Atomic Pd dispersed on PdCoB mesoporous nanospheres for ultrasensitive electrochemical detection of hydrogen peroxide released from cancer cells

Pd single-atom loaded PdCoB alloy mesoporous nanospheres (Pd-PdCoB SAMNs) exhibited exceptional peroxidase-like activity. • A electrochemical biosensor was developed using Pd-PdCoB SAMNs and DDA-Cu MOFs nanobelts for H 2 O 2 detection. • The constructed electrochemical biosensor demonstrated outstanding performance in the ultrasensitive detection of H 2 O 2 in cancer cells. Hydrogen peroxide (H 2 O 2 ), a key component of reactive oxygen species (ROS), plays a crucial role in monitoring the occurrence and progression of diseases, including cancer. However, convenient and reliable analysis of H 2 O 2 levels released from cancer cells has remained particularly challenging. Herein, we proposed Pd single-atom loaded PdCoB alloy mesoporous nanospheres (Pd-PdCoB SAMNs) and 1,5-Diamino-4,8-dihydroxyanthraquinone-Cu metal-organic frameworks (DDA-Cu MOFs) for the reliable detection of the H 2 O 2 levels. In this approach, atomically dispersed Pd anchored on PdCoB mesoporous nanospheres (MNSs) with peroxidase-like catalytic activity, with the assistance of DDA-Cu MOFs nanobelts were then modified on the glassy carbon electrode (GCE) substrate to enhance its conductivity. Benefiting from the excellent electrochemical performances of Pd-PdCoB SAMNs and DDA-Cu MOFs, a detection limit of 0.74 μM and a linear detection range of 0.1 to 0.8 × 10 4  μM was achieved, and a high accuracy was reached in distinguishing the release of tumor cell lines from that of normal cells. Empowered by the intrinsic sensitivity and selectivity, the proposed approach will lead to the development of a universal platform for reliable small molecular. Download: Download high-res image (451KB) Download: Download full-size image