One‐step synthesis of cationic gold nanoclusters with high catalytic activity on luminol chemiluminescence reaction

• Published in: Luminescence (Chichester, England) England), 2021-02, Vol.36 (1), p.85-93
• Main Authors: Huang, Yongxin, Yue, Ningning, Li, Ying, Han, Lu, Fan, Aiping
• Format: Article
• Language: English
• Subjects: Biological analysis; Catalytic activity; cationic gold nanoclusters; Cations; Chemical activity; Chemiluminescence; Current carriers; Glutathione; Gold; luminol; Nanoclusters; Polyamines; Polyethyleneimine; Reagents; Synergistic effect
• ISSN: 1522-7235; 1522-7243
• DOI: 10.1002/bio.3916

The present study reports a one‐step synthesis method for the preparation of cationic gold nanoclusters (Au NCs). Polyethyleneimine (PEI), a positively charged hyperbranched polyamine, was selected as the capping reagent. Glutathione showed a synergistic effect on the formation of the small size of cationic Au NCs. The prepared cationic Au NCs have a size less than 2 nm and carry a positive charge in solution with pH less than 11. The cationic PEI–Au NCs‐triggered luminol chemiluminescence (CL) reactions showed slow and intense CL profiles. The maximum CL intensity can be obtained within 10 min and the CL signal maintained almost the same within 30 min. A linear increase of CL intensity was observed in the presence of an increasing concentration of cationic Au NCs ranging from 0.030 μM to 15 μM. The linear response of the cationic Au NCs in the CL reaction and the glow‐type CL profile make the proposed CL reaction have broad application prospects in the field of biological analysis and CL imaging. A one‐step synthesis method was developed for the preparation of PEI‐capped Au NCs which have high catalytic activity in a luminol–H2O2 CL reaction. The PEI–Au NC‐triggered luminol CL reaction showed a glow‐type CL profile and the CL signal was maintained almost the same within 30 min.