Gap-enhanced resonance Raman tags for live-cell imaging

Area of Science:

• Biomedical imaging
• Nanotechnology
• Spectroscopy

Background:

• Surface-enhanced Raman scattering (SERS) nanotags offer high specificity and multiplexing for live-cell imaging.
• Limitations in long-term live-cell Raman imaging stem from photodamage caused by high laser power and long exposure times.
• Developing advanced nanotags is crucial for overcoming these limitations and enabling detailed cellular process observation.

Purpose of the Study:

• To develop novel ultrabright gap-enhanced resonance Raman tags (GERRTs) for overcoming photodamage limitations in live-cell imaging.
• To enable high-speed and long-term live-cell imaging with reduced laser exposure.
• To demonstrate the potential of GERRTs for capturing dynamic cellular processes with high temporal resolution.

Main Methods:

• Fabrication of GERRTs using a petal-like gold core and a silver shell with embedded IR-780 reporter.
• Characterization of GERRT Raman intensity at the single-nanoparticle level in solution and solid states.
• Application of GERRTs for high-resolution, time-lapse live-cell Raman imaging using low laser power (50 μW) and short exposure times (1 ms).

Main Results:

• GERRTs demonstrated ultrahigh Raman intensity, enabling single-nanoparticle detection.
• High-resolution, time-lapse live-cell imaging was achieved with significantly reduced laser power and exposure time.
• The developed GERRTs allowed for tracking living cells over extended periods with minimal photodamage.

Conclusions:

• Ultrabright GERRTs effectively resolve the photodamage issue in long-term live-cell Raman imaging.
• These nanotags facilitate ultrasensitive, low-phototoxic imaging, opening new avenues for studying dynamic cellular processes.
• GERRTs offer a promising tool for high-speed, long-term observation of living cells with unprecedented detail.