Application of Single-Atom Nanozymes in the Detection of Small Biomolecules: A Review

Single-atom nanozymes (SANs) with atomically dispersed metal sites show great potential in small biomolecule detection. This review first summarizes SAN synthesis (wet chemistry, atomic layer deposition, etc.), structural features (tunable coordination, metal-carrier interactions), and catalytic mechanisms (synergistic effects, d-band modulation). Afterwards, this review focuses on the applications of SANs in detecting small biomolecules, including glucose, glutathione, uric acid, ascorbic acid, hydrogen peroxide, and dopamine via colorimetry, fluorescence, and electrochemistry. Challenges such as matrix interference and stability, along with future directions in flexible electronics and clinical translation, are discussed, aiming to advance SAN-based detection technologies.