Protein Enhanced Near-Infrared Fluorescence of AuNPs and Its Application for Protein Determination

Abstract

The 15∼25 nm water soluble and stable gold nanoparticles were synthesized and studied for their spectral properties and interactions with proteins. Results showed that 15 nm gold nanoparticles can emit near infrared fluorescence with an emission peak of 811.2 nm under the excitation of 538 nm. The study also showed that proteins can obviously enhance the near infrared fluorescence intensity of gold nanoparticles. Under the optimized conditions, there is a linear relationship between the fluorescence intensity enhancement of the system and the concentrations of the proteins, which can be used in a new method for the determination of trace proteins. The mechanisms of the interaction and the fluorescence enhancement of the nano-gold-protein system were also studied.

Keywords:

• Au nanoparticles
• Near infrared fluorescence
• Proteins

Acknowledgments

We thank the National Natural Science Foundation of China (20575035) and Natural Science Foundation of Shandong Province (023100101) for the support of this work.