Characterization of nanopharmaceuticals with field-flow fractionation and light scattering (FFF-MALS-DLS)

Význam tématu

Advances in nanopharmaceutical delivery systems demand precise characterization of particle size, structure and composition. Conventional techniques such as dynamic light scattering (DLS) or electron microscopy face trade-offs between throughput, resolution and statistical robustness. Coupling field-flow fractionation (FFF) with multi-angle light scattering (MALS) and DLS addresses these limitations, offering automated, high-resolution separation and quantitation of nanoparticle populations, critical for formulation development, quality control and regulatory compliance.

Cíle a přehled studie

This white paper describes the principles, instrumentation and applications of the FFF-MALS-DLS platform for nanopharmaceutical analysis. Key aims are to demonstrate:

• Size‐based separation across 1–1 000 nm particles
• Quantitative size distributions, molar mass and concentration
• Structural insights including shape factor and encapsulation efficiency
• Workflows for liposomes, virus‐like particles and polymer carriers

Použitá metodika a instrumentace

The integrated system comprises:

• Eclipse™ FFF controller with separation channel and cross-flow membrane
• DAWN™ MALS detector for multi-angle scattering
• WyattQELS™ DLS module embedded within MALS for hydrodynamic sizing
• Optilab™ differential refractometer and optional UV/Vis or fluorescence detectors
• Standard HPLC components and VISION™ software for automated control and data analysis

FFF separates particles by balancing convective cross-flow against diffusion in a laminar channel, yielding size‐dependent retention times.

Hlavní výsledky a diskuse

• Latex standards from 25 to 150 nm were baseline‐resolved, confirming high size selectivity.
• Influenza virus subpopulations were quantified in number and size, matching TEM counts within 5 %.
• Liposome samples (empty vs. drug‐loaded) exhibited identical hydrodynamic radii but distinct rms radii and shape factors, revealing core loading.
• Rod-like particles (e.g. nanotubes) were distinguished from spheres via angular light‐scattering fits.
• Conjugate analysis combining MALS and dual concentration detectors enabled quantitation of drug-to-carrier ratios.
• Encapsulation efficiency of small molecules in polymersomes was cross-validated by measuring free drug in the cross-flow outlet and nanoparticle mass shifts.

Přínosy a praktické využití metody

• High statistical robustness from ensemble sampling and continuous fractionation
• Minimal sample preparation; FFF channel performs in-line cleanup and dialysis
• Automated fraction collection for off-line assays or process control
• Absolute sizing and molar mass without calibration standards
• Capability to monitor complex, multidisperse drug carriers and bioconjugates

Budoucí trendy a možnosti využití

• Integration of electrophoretic FFF for charge and zeta-potential separation
• Real-time process analytics using ultraDAWN for in-flow monitoring of continuous manufacturing
• Expansion of detector arrays (e.g. Raman, mass spectrometry) for deeper compositional profiling
• Improved simulation software for virtual method development and robust flow modeling

Závěr

FFF-MALS-DLS addresses critical needs in nanopharmaceutical characterization by combining size-based separation with multi-detector analysis. Its unique ability to resolve, quantify and structurally characterize nanoparticles makes it indispensable for R&D, QC and regulatory submissions in advanced drug delivery.

Reference

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