Gold nanoparticles conjugated dopamine as sensing platform for SERS detection

Area of Science:

• Nanotechnology
• Analytical Chemistry
• Biochemistry

Background:

• Gold nanoparticles (Au NPs) offer unique surface properties for sensing applications.
• Dopamine and its oxidized form, dopamine-quinone, play roles in biological processes.
• Surface-enhanced Raman scattering (SERS) spectroscopy is a sensitive technique for molecular detection.

Purpose of the Study:

• To investigate the properties of dopamine and dopamine-quinone on Au NPs.
• To develop a SERS-based sensing platform for dopamine and dopamine-quinone.
• To explore the application of this platform for detecting glutathione (GSH) and superoxide radical anion (O2(-)) in biological systems.

Main Methods:

• Construction of an Au NPs/dopamine sensing platform.
• Utilizing SERS spectroscopy for analysis at different pH levels.
• Investigating the redox reactions between dopamine-quinone, GSH, and O2(-).
• Demonstrating the platform's utility in living HeLa and HL-7702 cells for real-time reactive oxygen species (ROS) monitoring.

Main Results:

• Au NPs/dopamine-quinone showed characteristic Raman bands at pH 10.0, while Au NPs/dopamine showed no obvious bands at pH 6.0.
• The platform successfully detected and quantified GSH and O2(-).
• Real-time monitoring of reactive oxygen species (ROS) concentration changes in living cells was achieved.

Conclusions:

• The developed Au NPs/dopamine platform is effective for SERS-based detection of dopamine and dopamine-quinone.
• This platform enables the quantification of GSH and O2(-), with potential applications in biological sensing.
• The platform demonstrates real-time ROS monitoring in living cells, highlighting its biological relevance.