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Updated: Jun 28, 2026

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging
06:34

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging

Published on: September 2, 2016

Quantifying diffusion in mucosal systems by pulsed-gradient spin-echo NMR

Paola Occhipinti1, Peter C Griffiths

  • 1School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, UK. griffithspc@cf.ac.uk

Advanced Drug Delivery Reviews
|October 23, 2008
PubMed

Insights

Mucus barriers hinder nanoparticle drug delivery. This review explores nano-object diffusion in mucus and introduces pulsed-gradient spin-echo NMR (PGSE-NMR) as a novel investigation tool.

Area of Science:

  • Biomedical Engineering
  • Materials Science
  • Pharmacology

Background:

  • Mucus covers mammalian epithelial surfaces, acting as a protective barrier against foreign particles.
  • This mucus layer poses a significant challenge for the effective delivery of nano-sized drug delivery systems to target mucosal tissues.
  • Understanding nano-object diffusion within mucus is crucial for developing advanced drug delivery strategies.

Purpose of the Study:

  • To review the current knowledge on the diffusion of nano-sized structures within mucosal networks.
  • To introduce pulsed-gradient spin-echo NMR (PGSE-NMR) as a promising new technique for studying molecular mobility in mucus.
  • To highlight the challenges and opportunities in nanoparticle drug delivery across mucosal barriers.

Main Methods:

  • Review of existing literature on nanoparticle diffusion in mucus.
  • Discussion of techniques such as multiple-particle tracking (MPT), diffusion chamber studies, and fluorescence recovery after photobleaching (FRAP).
  • Introduction to pulsed-gradient spin-echo NMR (PGSE-NMR) principles and applications for biological gel analysis.

Main Results:

  • Existing methods provide insights into nano-object diffusion within mucus.
  • PGSE-NMR offers a potentially powerful, non-invasive method for characterizing molecular mobility in complex biological networks.
  • The review synthesizes current understanding, identifying gaps and future research directions.

Conclusions:

  • Effective mucus penetration is key for successful mucosal drug delivery.
  • PGSE-NMR presents a novel approach to quantify nano-object diffusion in mucus and related biological gels.
  • Further research utilizing PGSE-NMR could significantly advance the design of drug delivery systems for mucosal applications.

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