Single atom nanozymes (SAzymes) represent the state-of-the-art technology in nanomaterial-based catalysis, which have attracted attentions in catalysis,
cancer treatment, disinfection and biosensing fields. However, numerous SAzymes suffered from low aqueous dispersion and without recognition capacity, which impeded their applications in bioanalysis. Herein, we engineered
DNA onto SAzymes to obtain the
DNA/SAzymes conjugates, which significantly improved the aqueous dispersion and recognition ability of SAzymes. We synthesized
iron SAzymes (Fe-N-C SAzymes) as the catalytic nanomaterials, and investigated the interactions between Fe-N-C SAzymes and
DNA. We compared A15, T15 and C15 adsorption of Fe-N-C SAzymes in
HEPES containing 2 mM
MgCl2. We found that 50 μg mL-1 Fe-N-C SAzymes produced nearly 100% A15 adsorption, 90% T15 adsorption and only 69% C15 adsorption, indicating that
adenine and
thymine had higher adsorption affinity on Fe-N-C SAzymes. More importantly,
DNA modification did not affect the
peroxidase-like activity of Fe-N-C SAzymes and the bioactivity of the adsorbed
DNA. Taking the advantage of the diblock
DNA with one DNA sequence (
adenine) binding to Fe-N-C SAzymes and the other DNA sequence (i.e., aptamer) binding to
cancer cells, we designed
Apt/Fe-N-C SAzymes for colorimetric detection of
cancer cells, which offered new insights for the use of SAzymes in biomedicine.