Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Polymers: Molecular Weight Distribution01:10

Polymers: Molecular Weight Distribution

For any given polymer, the weight average molecular weight (Mw) is higher than, if not equal to, the number average molecular weight (Mn). The only situation in which the weight average molecular weight and the number average molecular weight are equal is when a polymer consists only of chains with equal molecular weight. However, this never happens in a synthetic polymer, since it is difficult to control the polymerization process up to a molecular level with accuracy to a hundred percent.
Protein Diffusion in the Membrane01:24

Protein Diffusion in the Membrane

Proteins show rotational as well as lateral diffusion across the membrane. The lateral diffusion of proteins was confirmed through the cell fusion experiment where mouse and human cells were fused, resulting in hybrid cells. When the human and mouse cells fused, the specific membrane proteins on human and mouse cells were marked with the red and green-fluorescent markers, respectively. Initially, the red and green fluorescence was located on the respective hemisphere of the cell. As time...
Determination of Molar Masses of Polymers I01:24

Determination of Molar Masses of Polymers I

Polymerization produces macromolecules with a range of chain lengths due to the random nature of molecular growth processes. As chains form and terminate at different stages, a single polymer sample contains molecules of varying sizes rather than a uniform structure. This variability is described using average molar masses and distribution-related parameters, which together provide a comprehensive understanding of polymer characteristics.The distribution of molar masses plays a critical role in...
Diffusion01:12

Diffusion

Diffusion is the passive movement of substances down their concentration gradients—requiring no expenditure of cellular energy. Substances, such as molecules or ions, diffuse from an area of high concentration to an area of low concentration in the cytosol or across membranes. Eventually, the concentration will even out, with the substance moving randomly but causing no net change in concentration. Such a state is called dynamic equilibrium, which is essential for maintaining overall...
Diffusion01:21

Diffusion

Diffusion is a type of passive transport. In passive transport, a substance tends to move from an area of high concentration to an area of low concentration until the concentration is equal across the space. For example, take the diffusion of substances through the air. When someone opens a perfume bottle in a room filled with people, the perfume is at its highest concentration in the bottle and is at its lowest at the edges of the room. The perfume vapor will diffuse, or spread away, from the...
Passive Diffusion: Overview and Kinetics01:17

Passive Diffusion: Overview and Kinetics

Passive diffusion is a critical process that allows small lipophilic drugs to cross the cell membrane along a concentration gradient. This mechanism's efficiency depends on four primary factors: the membrane's surface area, the drug's lipid-water partition coefficient, the concentration gradient, and the membrane's thickness.
When administered orally, drugs establish a substantial concentration gradient between the gastrointestinal (GI) lumen and the bloodstream, expediting their diffusion into...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Active Brownian particles in quenched matrices.

The Journal of chemical physics·2026
Same author

Beyond the Paddle-Wheel Mechanism: Hop Function Analysis of Ion Transport in Organic Ionic Plastic Crystals.

Journal of the American Chemical Society·2026
Same author

Hopping dynamics of a tracer particle confined in a fluctuating lattice.

Soft matter·2026
Same author

Effectiveness and safety of motion style acupuncture treatment for acute neck pain: a multicenter randomized controlled trial.

Chinese medicine·2026
Same author

Non-Gaussian rotational diffusion and swing motion of dumbbell probes in two-dimensional colloids.

The Journal of chemical physics·2025
Same author

Evaluating the Clinical Efficacy of Membrane-Assisted Regenerative Therapy in Peri-Implantitis Management: A Comprehensive Review Incorporating Systematic Review Evidence.

Materials (Basel, Switzerland)·2025

Related Experiment Video

Updated: May 17, 2026

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
06:55

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

Published on: September 26, 2016

Effect of polydispersity on diffusion in random obstacle matrices.

Hyun Woo Cho1, Gyemin Kwon, Bong June Sung

  • 1Department of Chemistry, Sogang University, Seoul, Republic of Korea.

Physical Review Letters
|October 30, 2012
PubMed
Summary

Particle size variation significantly impacts tracer diffusion in disordered materials. This study reveals tracer movement is highly sensitive to matrix particle polydispersity, affecting diffusion rates and percolation thresholds.

More Related Videos

Single-Molecule Diffusion and Assembly on Polymer-Crowded Lipid Membranes
10:43

Single-Molecule Diffusion and Assembly on Polymer-Crowded Lipid Membranes

Published on: July 19, 2022

Controlled Synthesis and Fluorescence Tracking of Highly Uniform Poly(N-isopropylacrylamide) Microgels
11:34

Controlled Synthesis and Fluorescence Tracking of Highly Uniform Poly(N-isopropylacrylamide) Microgels

Published on: September 8, 2016

Related Experiment Videos

Last Updated: May 17, 2026

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
06:55

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

Published on: September 26, 2016

Single-Molecule Diffusion and Assembly on Polymer-Crowded Lipid Membranes
10:43

Single-Molecule Diffusion and Assembly on Polymer-Crowded Lipid Membranes

Published on: July 19, 2022

Controlled Synthesis and Fluorescence Tracking of Highly Uniform Poly(N-isopropylacrylamide) Microgels
11:34

Controlled Synthesis and Fluorescence Tracking of Highly Uniform Poly(N-isopropylacrylamide) Microgels

Published on: September 8, 2016

Area of Science:

  • Physics
  • Statistical Mechanics
  • Materials Science

Background:

  • Tracer dynamics in disordered matrices are crucial for understanding cellular crowding and fluid diffusion in porous media.
  • Matrices are often modeled as spatially frozen particles, but particle size variation (polydispersity) effects are less understood.

Purpose of the Study:

  • To investigate the influence of matrix particle polydispersity on tracer diffusion dynamics.
  • To quantify the relationship between polydispersity, area fraction, and tracer diffusion in a 2D system.

Main Methods:

  • Simulated a 2D system of hard disks diffusing among hard disk obstacles.
  • Varied the polydispersity of the matrix particles.
  • Calculated the pore percolation threshold using Apollonius diagrams.

Main Results:

  • Tracer diffusion is highly sensitive to matrix particle polydispersity, even at a fixed average size and area fraction.
  • A scaling relation D~(φ(c)-φ(m))(μ-β) was identified for the diffusion constant (D), applicable across all polydispersity values.
  • The pore percolation threshold was determined as a function of matrix area fraction (φ(m)) and percolation threshold (φ(c)).

Conclusions:

  • Matrix particle polydispersity is a critical factor influencing tracer diffusion in disordered systems.
  • The established scaling relation provides a predictive framework for tracer diffusion under varying polydispersity.
  • Understanding these dynamics is key for applications in biophysics and porous media research.