Peptide-protected metal nanoclusters

In this chapter, peptide-protected metal nanoclusters are reviewed from two aspects: designed peptide-protected fluorescent nanoclusters (FNCs), and tripeptide-protected FNCs. For designed peptide-protected FNCs, the effect of length and amino acid sequence on the core structure size of blue, green, orange, red, and NIR light-emitting clusters are discussed. This is followed by reporting their synthetic protocols and key parameters in the formation of FNCs such as quantum yield, metal:peptide mole ratio, temperature, pH. In the case of designing peptide-based bi/multifunctional fluorescent probes, critical points together with detection mechanism and its applications are also investigated. The second category more focuses on the natural tripeptide glutathione (GSH), its various application, and different advised approaches for enhancement of the emission quantum yield and function of GSH-FNCs. The development of self-assembled and designed tripeptides-protected FNCs is also discussed. In the end, challenges and future outlook in this emerging area are considered.