A multiwavelength emission detector for analytical ultracentrifugation

Area of Science:

• Analytical Chemistry
• Materials Science
• Nanotechnology

Background:

• Characterizing nanoparticle optical properties is crucial for understanding their behavior and applications.
• Existing methods for analyzing nanoparticle fluorescence and size distribution can be limited in scope or accuracy.
• Multiwavelength analytical ultracentrifugation (MWL-AUC) is established for extinction-based analysis, but emission properties require new approaches.

Purpose of the Study:

• To introduce and validate a novel detector for multiwavelength emission analytical ultracentrifugation (MWE-AUC).
• To enable the measurement of size- and composition-dependent fluorescence properties of nanoparticle ensembles.
• To provide a comprehensive optical characterization framework combining extinction and emission properties.

Main Methods:

• Development and implementation of a new MWE-AUC detector.
• Validation against a benchtop photoluminescence spectrometer and established MWL-AUC.
• Analysis of fluorescent proteins, silica particles, graphene oxide nanoplatelets, and CdSe/ZnS quantum dots.

Main Results:

• The new MWE-AUC setup accurately reproduces sedimentation and diffusion coefficients.
• The device successfully provides meaningful fluorescence spectra for various nanoparticles.
• Simultaneous extraction of spectra and size for broad distributions (graphene oxide) and size-dependent spectral shifts (quantum dots) were achieved.

Conclusions:

• The MWE-AUC detector offers a powerful new tool for detailed optical characterization of nanoparticles.
• The combined MWE- and MWL-AUC approach provides a comprehensive framework for analyzing both extinction and emission properties.
• This technology advances the understanding and application of nanomaterials and macromolecules.