Experimental Study On Energy Transfer Between Gold Nanoparticles And Gold Nanoparticles With Different Shapes

Excitation energy transfer is a fundamental physical process due to near-field interaction between fluorophores and quenchers. Energy transfer rate have a close relation with the separation distance between energy donors and acceptors, which can be used to measure the separation distance at the nanoscales, thus also referred to as molecular ruler. Gold nanoclusters with stability fluorescence properties, light fastness is strong, its fluorescence spectrum can be adjusted by the size of clusters, thus, they are widely used in biological imaging, detection of heavy metals, biomarkers and other fields. As a result, we desired to develop a novel molecular ruler based on the biocompatible gold nanoclusters.In this work, We were prepared stable bovine serum albumin-encapsulated AuNCs. Serum albumin-encapsulated AuNCs is the energy donor, and different nanometal(gold nanorods, gold nanoparticles) is the energy receptor. The excitation energy transfer between protein-encapsulated gold nanoclusters and metals has been investigated using photoluminescence spectroscopy and lifetime. We found that the excitation energy transfer can occur from gold nanoclusters to metals even the existence of a protein spacer. Gold nanoclusters appear fluorescence quenching, the energy transfer from gold nanoclusters to other metal nanoparticles. Use Persson-Lang model, dipole-metal-surface interaction calculation feature length, compare the rate of FRET and NSET(nano-metal surface energy transfer)in the energy transfer system of gold nanoclusters and gold nanoparticles. The mechanism for such long-range energy transfer might be attributed to surface energy transfer between one-dimension dipole emitters and metal surface mediated by the excitation of surface plasmons. Therefore, we innovatively introduced gold nanoclusters and metal nanoparticles consisting of a NSET system, which can be used as a new long distance molecular ruler.