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

Osmosis01:30

Osmosis

8.2K
Osmosis is the movement of free water molecules through a semipermeable membrane.  The water's concentration gradient across the membrane is inversely proportional to the solutes' concentration. Whereas diffusion transports material across membranes and within cells, osmosis transports only water across a membrane, and the membrane limits the diffusion of solutes in the water. Osmosis is a special case of diffusion.
Water, like other substances, moves from a high concentration of...
8.2K
Osmosis and Osmotic Pressure of Solutions02:40

Osmosis and Osmotic Pressure of Solutions

42.7K
A number of natural and synthetic materials exhibit selective permeation, meaning that only molecules or ions of a certain size, shape, polarity, charge, and so forth, are capable of passing through (permeating) the material. Biological cell membranes provide elegant examples of selective permeation in nature, while dialysis tubing used to remove metabolic wastes from blood is a more simplistic technological example. Regardless of how they may be fabricated, these materials are generally...
42.7K
Fluid Movement Between Compartments01:18

Fluid Movement Between Compartments

1.9K
The force applied by fluids against a surface, known as hydrostatic pressure, initiates the transfer of fluid among different compartments. Within our blood vessels, the blood's hydrostatic pressure is a result of the heart's pumping action. At the arteriolar end of capillaries, hydrostatic pressure (capillary blood pressure) exceeds the opposing colloid osmotic pressure created primarily by plasma proteins like albumin. This discrepancy in pressure propels plasma and nutrients from the...
1.9K
Reabsorption and Secretion in the Loop of Henle01:17

Reabsorption and Secretion in the Loop of Henle

1.9K
The thick ascending limb of the nephron loop has Na+–K+–2Cl− symporters in the apical membranes of its cells. These symporters simultaneously reclaim one sodium ion, one potassium ion, and two chloride ions from the tubular fluid. Sodium ions are actively transported into the interstitial fluid at the base and sides of the cell, diffusing into the vasa recta. Chloride ions move through leakage channels in the basolateral membrane into the interstitial fluid and then into the...
1.9K
Facilitated Transport01:19

Facilitated Transport

14.9K
The chemical and physical properties of plasma membranes cause them to be selectively permeable. Since plasma membranes have both hydrophobic and hydrophilic regions, substances need to be able to transverse both regions. The hydrophobic area of membranes repels substances such as charged ions. Therefore, such substances need special membrane proteins to cross a membrane successfully. In  facilitated transport, also known as facilitated diffusion, molecules and ions travel across a...
14.9K
The Significance of Membrane Transport01:44

The Significance of Membrane Transport

33.1K
The transport of solutes across the cell membrane is essential for metabolic processes, like maintaining cell size and volume, generating the action potential, exchanging nutrients and gases, etc. Membrane transport can be either passive or active. It can be simple diffusion, facilitated, or mediated transport aided by transport proteins such as transporters and channels.
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...
33.1K

You might also read

Related Articles

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

Sort by
Same author

Retreaded tires are an overlooked source of microplastics with distinct additive leaching and ecotoxicity.

Communications earth & environment·2026
Same author

Generalizable and Transferable Machine Learning Enables Accelerated Metal-Organic Framework Discovery in Gas Separations.

Environmental science & technology·2026
Same author

In Situ Oxygen Shuttling within a Bilayer Electrified Membrane Enables Aeration-Free Electro-Fenton Water Purification.

ACS nano·2026
Same author

A stage-based framework for closed-loop recycling of polymeric composite membranes.

Science advances·2026
Same author

Rapid and Low-Energy Boron Removal Enabled by Carbon Cloth-Integrated Bipolar Membrane Electrodialysis.

Environmental science & technology·2026
Same author

Straw Return Enhances Photooxidative Disintegration of Mulch Film and Microplastics Formation in Farmlands.

Environmental science & technology·2026

Related Experiment Video

Updated: Oct 10, 2025

Ion-Exchange Membranes for the Fabrication of Reverse Electrodialysis Device
07:55

Ion-Exchange Membranes for the Fabrication of Reverse Electrodialysis Device

Published on: July 20, 2021

11.0K

Salt and Water Transport in Reverse Osmosis Membranes: Beyond the Solution-Diffusion Model.

Li Wang1, Tianchi Cao1, Jouke E Dykstra2

  • 1Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States.

Environmental Science & Technology
|December 8, 2021
PubMed
Summary
This summary is machine-generated.

A new solution-friction model for reverse osmosis (RO) reveals complex ion-water-membrane interactions, improving understanding of salt-water separation beyond the traditional solution-diffusion model.

Keywords:
ion transportreverse osmosissalt permeabilitysolution-diffusion modelsolution-friction modelwater permeability

More Related Videos

Proof-of-Concept for Gas-Entrapping Membranes Derived from Water-Loving SiO2/Si/SiO2 Wafers for Green Desalination
09:39

Proof-of-Concept for Gas-Entrapping Membranes Derived from Water-Loving SiO2/Si/SiO2 Wafers for Green Desalination

Published on: March 1, 2020

7.6K
Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
11:55

Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution

Published on: August 16, 2016

11.8K

Related Experiment Videos

Last Updated: Oct 10, 2025

Ion-Exchange Membranes for the Fabrication of Reverse Electrodialysis Device
07:55

Ion-Exchange Membranes for the Fabrication of Reverse Electrodialysis Device

Published on: July 20, 2021

11.0K
Proof-of-Concept for Gas-Entrapping Membranes Derived from Water-Loving SiO2/Si/SiO2 Wafers for Green Desalination
09:39

Proof-of-Concept for Gas-Entrapping Membranes Derived from Water-Loving SiO2/Si/SiO2 Wafers for Green Desalination

Published on: March 1, 2020

7.6K
Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
11:55

Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution

Published on: August 16, 2016

11.8K

Area of Science:

  • Membrane science
  • Physical chemistry
  • Chemical engineering

Background:

  • The solution-diffusion (SD) model is standard for reverse osmosis (RO) but lacks detail on molecular transport.
  • Accurate modeling of water and ion transport is crucial for advancing RO technology.

Purpose of the Study:

  • To develop a new ion transport model for RO, termed the solution-friction model.
  • To incorporate partitioning and inter-species friction mechanisms into RO transport modeling.
  • To challenge the assumptions of the traditional SD model.

Main Methods:

  • Developed the solution-friction model using the extended Nernst-Planck equation.
  • Incorporated friction terms for ion-membrane, water-membrane, and water-ion interactions.
  • Validated the model with experimental salt rejection and permeate flux data.

Main Results:

  • The solution-friction model accurately predicts RO performance.
  • Salt permeability shows strong dependence on feed concentration and pressure, unlike SD model predictions.
  • Cross-membrane transport, not membrane-internal, dominates pressure drop, contradicting SD assumptions.

Conclusions:

  • The solution-friction model offers a more mechanistic understanding of RO transport.
  • This model highlights the limitations of the SD model in describing complex interactions.
  • Findings provide a basis for optimizing RO processes through a deeper mechanistic insight.