Ultra-efficient label-free cell death detection based on multifunctional colorimetric fluorescent in-situ silver nanocluster/graphene nanohybridzyme and its application in environmental biological samples and cellular imaging

Abstract

AgNCs/graphene NHZs) was designed and employed for dual-modal naked-eye colorimetric and fluorometric detection of cell death biomarkers involved in ferroptosis, cuproptosis, and apoptosis. The interesting feature of developed NHZs is the colorimetric speciation of “turn-on” Fe2+, Cu2+, and Cyt c and “turn-off” cysteine (Cys) and glutathione (GSH), and its speciation ability of Fe2+ from Fe3+as well. The presence of analytes causes a colorimetric limit of detection of 10.8–191 nM and fluorometric detection limit from 0.25 to 121 nM in the appropriate linear ranges, with fast times ranging 5–20 min. The designed NHZs were successfully employed for fluorescence imaging of HT29 human colon cancer and also quantitatively validated in just 2 μL of cell lysates, environmental, and biological samples. Compared to the semi-quantitative conventional Western blot and other cell death assays, the novelty of presented probe is low cost, simple preparation, high sensitivity, multifunctionallity, and dual-modality with the speciation and quantitative ability without using any targeting agent, which makes it appropriate for dual-modal tracking cell death processes and drug evaluation in a very short tim