Fluorescence Resonance Energy Transfer for Drug Loading Assessment in Reconstituted High-Density Lipoprotein...

Area of Science:

• Biotechnology and Nanomedicine
• Biophysics
• Materials Science

Background:

• High-density lipoprotein nanoparticles (NPs) show promise for targeted drug delivery.
• A key challenge is monitoring drug load and release efficiency in real-time.
• Current methods lack effective strategies for assessing NP payload and integrity.

Purpose of the Study:

• To develop a novel method using enhanced Förster Resonance Energy Transfer (FRET) to assess particle load and monitor payload release from NPs.
• To establish a quantitative approach for evaluating nanoparticle drug loading, integrity, and release efficiency.

Main Methods:

• NPs were labeled with donor molecules in the lipid phase and acceptor molecules in the core.
• Enhanced FRET efficiency was measured at distances larger than the Förster distance (R0).
• A theoretical model was developed to analyze nonradiative energy transfer from single donors to multiple acceptors in a spherical core.

Main Results:

• Load-dependent shortening of donor fluorescence lifetime and acceptor intensity decay confirmed FRET at large distances (>100 Å).
• FRET efficiency correlated with the number of acceptors, enabling estimation of nanoparticle load.
• Distinct changes in donor and acceptor emissions indicated particle disintegration and payload release.

Conclusions:

• Enhanced FRET provides a novel strategy for assessing NP core load, monitoring NP integrity, and evaluating payload release efficiency.
• This method offers a significant improvement for quality assessment of drug delivery systems.
• FRET-enabled NPs serve as an improved tool for real-time monitoring of drug delivery vehicles.