Detecting plasmon resonance energy transfer with differential interference contrast microscopy.

Area of Science:

• Nanotechnology
• Biophysics
• Cell Biology

Background:

• Gold nanoparticles possess unique plasmonic properties, making them suitable for probing intracellular environments and energy transfer.
• Plasmon Resonance Energy Transfer (PRET) involves energy transfer from a plasmonic nanoparticle donor to an acceptor molecule, detectable via nanoparticle quenching.

Purpose of the Study:

• To investigate Plasmon Resonance Energy Transfer (PRET) using gold nanospheres as donors and cytochrome c as acceptors.
• To monitor PRET dynamics in real-time at the single-particle level.
• To assess the reversibility of PRET and its occurrence within living cells.

Main Methods:

• Utilized gold nanospheres as plasmonic donors and cytochrome c as acceptor molecules.
• Employed Differential Interference Contrast (DIC) microscopy for simultaneous observation of nanoparticles and cellular environments.
• Integrated specially designed microfluidic channels for controlled experiments.

Main Results:

• Successfully monitored single gold nanoparticle PRET in real-time using DIC microscopy.
• Demonstrated the reversibility of PRET by introducing phosphate-buffered saline.
• Observed PRET in gold nanoparticles internalized by HeLa cells during ethanol-induced apoptosis.

Conclusions:

• Single-particle PRET monitoring is feasible using gold nanoparticles and DIC microscopy.
• PRET dynamics are observable and reversible in controlled microfluidic environments.
• Gold nanoparticle-mediated PRET can be detected in living cells undergoing apoptosis, offering insights into cellular processes.