Related Experiment Video
Updated: Jul 31, 2025

Fabrication of Polymer Microspheres for Optical Resonator and Laser Applications
Published on: June 2, 2017
Revealing molecular diffusion dynamics in polymer microspheres by optical resonances.
Jiawei Wang1, Jin Li1, Shengqi Sun1
1School of Electronic and Information Engineering, Harbin Institute of Technology, Shenzhen 518055, China.
This study introduces a novel optical method for tracking small molecule diffusion in polymer microspheres. The technique precisely quantifies diffusion dynamics and swelling in micro-objects, offering a label-free approach.
Area of Science:
- Polymer Science
- Materials Science
- Physical Chemistry
Background:
- Understanding small molecule diffusion in polymers is crucial for various applications.
- Current methods often limit analysis to bulk materials or flat films.
- In situ analysis of diffusion in micro-objects remains challenging.
Purpose of the Study:
- To develop a high-precision, label-free method for in situ detection of diffusion dynamics in polymer micro-objects.
- To quantitatively analyze sorption, diffusion, and swelling of solvent molecules in polymer microspheres.
- To investigate non-Fickian diffusion contributions in glassy polymer-penetrant systems.
Main Methods:
- Utilizing optical whispering-gallery mode (WGM) resonances for in situ detection.
- Tracking WGM shifts to monitor interactions between solvent molecules and polymer microspheres.
- Analyzing the turning point of mode response indicating diffusion into the polymer core.
Main Results:
- Demonstrated quantitative analysis of sorption, diffusion, and swelling dynamics in polymer microspheres.
- Observed a distinct turning point in WGM response as diffusion penetrated the polymer core.
- Estimated solubility in glassy polymers consistent with Flory-Huggins theory predictions.
- Analyzed non-Fickian diffusion characteristics in the polymer-penetrant system.
Conclusions:
- Whispering-gallery mode resonances provide a powerful tool for studying diffusion in polymer micro-objects.
- The developed method offers high precision and label-free characterization of diffusion dynamics.
- This approach advances the understanding of molecular transport in complex polymer systems.
More Related Videos
06:55Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
11:34Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels
Published on: September 8, 2016
Related Concept Videos
Behavior of Gas Molecules: Molecular Diffusion, Mean Free Path, and Effusion
Protein Dynamics in Living Cells
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
Diffusion
Protein Diffusion in the Membrane