Peptide-capped functionalized Ag/Au bimetal nanoclusters with enhanced red fluorescence for lysosome-targeted imaging of hypochlorite in living cells

• Published in: Talanta (Oxford) Vol. 216; p. 120926
• Main Authors: Jia, Minna, Mi, Wenying, Guo, Shaoshi, Yang, Qing-Zheng, Jin, Yan, Shao, Na
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.08.2020
• Subjects: Fluorescence; Gold - chemistry; Hep G2 Cells; Humans; Hypochlorite; Hypochlorous Acid - analysis; Lysosome-targeted; Lysosomes - chemistry; Metal Nanoparticles - chemistry; Microscopy, Fluorescence; Optical Imaging; Peptide-capped nanoclusters; Peptides - chemistry; Silver - chemistry; Silver/gold bimetal nanoclusters; Tumor Cells, Cultured; Silver/gold bimetal nanoclusters; Peptide-capped nanoclusters; Hypochlorite; Lysosome-targeted
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2020.120926

Bioimaging probes for monitoring intracellular reactive oxygen species have important implications for cell biology research. Herein, we developed peptide-capped silver/gold nanoclusters (peptide@Ag/Au NCs) for lysosome-targeted imaging of hypochlorite (ClO−). The peptide@Ag/Au NCs were synthesized via a one-pot method using peptide as both a template and a reducing agent. The fluorescence intensity and absolute quantum yield of peptide@Ag/Au NCs were much higher than those of peptide-capped gold nanoclusters and silver nanoclusters. In the presence of ClO−, the fluorescence of peptide@Ag/Au NCs was quenched, accompanied by a redshift due to ClO−-induced oxidation of the peptide ligand and decreased Ag content in Ag/Au NCs. The relative fluorescence intensity F0/F had favourable linearity for ClO− concentrations in the range 0.1–100 μmol/L (R2 = 0.9954), with a detection limit (LOD) of 80 nmol/L. The lysosome-targeted peptide@Ag/Au NCs were applied to detect ClO− in lysosomes in living cells via fluorescence imaging. [Display omitted] •The peptide functionalized nanoclusters were rationally designed and had good cell penetrating ability.•The probe has lysosome-targeting capability for monitoring ClO− level in living cells.•The probe has good selectivity and sensitivity towards ClO− over other species commonly present in biological matrices.