Fig. 7.

a Detection progress of the Hg²⁺ in distilled and tap water samples with AuNZ-PAD based on the TMB–H₂O₂ catalytic reaction. b Principle of quantitative detection of Hg²⁺ ions in seawater (3.5% NaCl) using OEG-AuNPs compared with that using bare AuNPs. c Detection principle of TAC based on the reaction between antioxidants and H₂O₂ in the presence of Pt nanozymes as POD mimics. d Synthesis of cDNA@Pt@P-MOF(Fe) as the signal probe for the analysis of telomerase activity. e Preparation of Ag-Au/AgCl nanohybrid with OXD-like and POD-like activity and the working mechanism of Spm detection. GCE Glassy carbon electrode, TP telomerase primer.

Adapted from a Ref. [226], b Ref. [293]. c Ref. [301], d Ref. [302], e Ref. [303] with permission