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Updated: Jun 2, 2026
Plasmonic Trapping and Release of Nanoparticles in a Monitoring Environment
Published on: April 4, 2017
How stealthy are PEG-PLA nanoparticles? An NIR in vivo study combined with detailed size measurements
Andreas Schädlich1, Cornelia Rose, Judith Kuntsche
1Department of Pharmaceutical Technology and Biopharmaceutics, Martin Luther University Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, 06120 Halle (Saale), Germany.
Purpose:
Detailed in vivo and ex vivo analysis of nanoparticle distribution, accumulation and elimination processes were combined with comprehensive particle size characterizations.
Methods:
The in vivo fate of near infrared (NIR) nanoparticles in nude mice was carried out using the Maestro™ in vivo fluorescence imaging system. Asymmetrical field flow field fractionation (AF4) coupled with multi-angle laser light scattering (MALLS), photon correlation spectroscopy (PCS) and transmission electron microscopy (TEM) were employed for detailed in vitro characterization.
Results:
PEG-PLA block polymers were synthesized and used for the production of defined, stable, nontoxic nanoparticles. Nanoparticle analysis revealed narrow size distribution; AF4/MALLS permitted further accurate size evaluation. Multispectral fluorescence imaging made it possible to follow the in vivo fate non-invasively even in deep tissues over several days. Detailed fluorescence ex vivo imaging studies were performed and allowed to establish a calculation method to compare nanoparticle batches with varying fluorescence intensities.
Conclusion:
We combined narrow-size distributed nanoparticle batches with detailed in vitro characterization and the understanding of their in vivo fate using fluorescence imaging, confirming the wide possibilities of the non-invasive technique and presenting the basis to evaluate future size-dependent passive tumor accumulation studies.
