Silk fibroin-derived peptide directed silver nanoclusters for cell imaging

Area of Science:

• Biomaterials Science
• Nanotechnology
• Chemical Synthesis

Background:

• Peptide-templated synthesis offers a green route to novel nanomaterials.
• Silk fibroin peptides present unique functional properties for bioconjugation.
• Fluorescent metal nanoclusters are promising for bioimaging due to their unique optical properties.

Purpose of the Study:

• To synthesize and characterize fluorescent silver nanoclusters (Ag NCs) using a silk-derived peptide.
• To evaluate the potential of these Ag NCs for cell imaging applications.
• To assess the cytotoxicity of the synthesized Ag NCs.

Main Methods:

• One-pot green synthesis of Ag NCs using a C-terminal silk fibroin heavy chain peptide (CSH).
• Characterization using fluorescence spectroscopy, MALDI-TOF MS, and transmission electron microscopy (TEM).
• Application in cell imaging using murine preosteoblast MC3T3-E1 cells and MTT assay for cytotoxicity.

Main Results:

• Synthesized Ag NCs exhibit stable green fluorescence with a quantum yield of 1.1%.
• TEM analysis confirmed uniform, well-dispersed particles with an average diameter of 2.5 nm.
• Successful application in MC3T3-E1 cell imaging, with cytotoxicity observed at 600 μM CSH-Ag NCs.

Conclusions:

• A novel, facile method for fabricating aqueous fluorescent Ag NCs using a natural peptide template.
• Demonstrated utility of CSH-templated Ag NCs as fluorescent probes for bioimaging.
• Highlights the potential of peptide-based nanomaterials for biological tracking and diagnostics.