Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Flagella and Motility in Bacteria

Flagella and Motility in Bacteria

Flagella are specialized, thread-like structures that extend from a bacteria's cell envelope. They play a crucial role in motility and chemotaxis. Their structural organization and functioning exemplify sophisticated biological engineering, enabling bacterial survival and adaptability in diverse environments.Structure of the FlagellumA bacterial flagellum consists of three key components: the filament, the hook, and basal body. The filament, a long, helical structure composed of repeating...

Cell Motility through Blebbing

Cell Motility through Blebbing

Blebs are a type of membrane protrusion formed by the internal hydrostatic pressure of the cytoplasm. Blebs are observed in several cell types, including fibroblasts, immune cells, and single-celled organisms like the amoeba. The primary function of blebs is cell locomotion and apoptosis, but they are also found during necrosis and cell division. The life cycle of a bleb comprises an initiation phase followed by the expansion and retraction phases.
Blebbing Through the Matrix
In multicellular...

Stokes' Law

Stokes' Law

Viscous forces, like friction, are intermolecular forces that resist the relative motion of molecules over each other. When a solid body moves through a liquid, viscous forces drag it in the opposite direction. The force's magnitude depends on the solid's shape and size, as well as its speed and the liquid's coefficient of viscosity, density and temperature.
The expression for the force on a solid spherical object in a fluid is called Stokes' law. Stokes' law is valid only...

Viscosity of Fluid

Viscosity of Fluid

Viscosity measures the resistance a fluid offers to flow and deformation. It results from internal friction between layers of fluid moving relative to one another. Dynamic viscosity, denoted by the Greek letter mu (μ), quantifies the force needed to move one fluid layer over another. For Newtonian fluids like water and air, the relationship between the shearing stress and the rate of shearing strain is linear, meaning their viscosity remains constant regardless of the applied stress.

Viscosity

Viscosity

When water is poured into a glass, it falls freely and quickly, whereas if honey or maple syrup is poured over a pancake, it flows slowly and sticks to the surface of the container. This difference in the flow of different kinds of liquids arises due to the fluid friction between the liquid layers and the liquid and the surrounding material. This property of fluids is called fluid viscosity. In this example, water has a lower viscosity than honey and maple syrup.
The SI unit of viscosity is...

Actin Polymerization and Cell Motility

Actin Polymerization and Cell Motility

Actin is a family of globular proteins that are highly abundant in eukaryotic cells. It makes up approximately 1-5% of total cell protein concentration. Actin monomers polymerize to form a complex network of polarized filaments, the actin cytoskeleton, that plays a crucial role in many cellular processes, including cell motility, division, endocytosis, and metastasis of cancer cells.
Actin cytoskeleton dynamics can produce pushing, pulling, and resistance forces that help the cell to migrate....

You might also read

Related Articles

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

Sort by

Same author

Salt-Mediated Electro-Deformation of AAV Capsids Revealed by Nanopipette-Based Single-Particle Analysis.

Analytical chemistry·2026

Same author

Ring-Electrode AC Plasmonic Nanopore Sensing for DNA Load Characterization of Single Adeno-Associated Viruses.

Sensors (Basel, Switzerland)·2026

Same author

Quantitative Analysis of Protein-Receptor Binding Using Solid-State Nanopores: Accurate Measurement of Dissociation Constants for KREMEN1 and ASGR1 with SARS-CoV-2 Spike RBD Protein.

The journal of physical chemistry. B·2026

Same author

Single-Particle Analysis of Cargo-Dependent Deformation in Lipid Nanoparticles Using Resistive Pulse Sensing: Implications for Formulation Optimization and Quality Control of mRNA Nanomedicine.

ACS applied nano materials·2026

Same author

Directional Single-Protein Transport Enabled by 2D Material Heterointerfaces in Solid-State Nanopores: Implications for Single-Molecule Sensing.

ACS applied nano materials·2026

Same author

Mislabel Identification Using Transfer Learning-Based Ensemble Method.

IEEE access : practical innovations, open solutions·2026

Search research articles

Related Experiment Video

Updated: Dec 23, 2025

Biophysical Characterization of Flagellar Motor Functions

Biophysical Characterization of Flagellar Motor Functions

Published on: January 18, 2017

Heterogeneously flagellated microswimmer behavior in viscous fluids.

Louis William Rogowski¹, Micah Oxner¹, Jiannan Tang¹

¹Department of Mechanical Engineering, Southern Methodist University, 3101 Dyer Street, Suite 200, Dallas, Texas 75206, USA.

Biomicrofluidics

|April 29, 2020

Summary

This study created flagellated microswimmers from Salmonella typhimurium flagella. These microswimmers showed controlled movement and anomalous diffusion, with propulsion affected by magnetic field handedness.

More Related Videos

Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series

Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series

Published on: May 10, 2020

Chemotactic Response of Marine Micro-Organisms to Micro-Scale Nutrient Layers

Chemotactic Response of Marine Micro-Organisms to Micro-Scale Nutrient Layers

Published on: May 28, 2007

Related Experiment Videos

Last Updated: Dec 23, 2025

Biophysical Characterization of Flagellar Motor Functions

Biophysical Characterization of Flagellar Motor Functions

Published on: January 18, 2017

Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series

Investigating Flagella-Driven Motility in Escherichia coli by Applying Three Established Techniques in a Series

Published on: May 10, 2020

Chemotactic Response of Marine Micro-Organisms to Micro-Scale Nutrient Layers

Chemotactic Response of Marine Micro-Organisms to Micro-Scale Nutrient Layers

Published on: May 28, 2007

Area of Science:

Biophysics
Microfluidics
Synthetic Biology

Background:

Microswimmers offer potential for targeted drug delivery and diagnostics.
Controlling microswimmer behavior in complex fluids remains a significant challenge.

Purpose of the Study:

To engineer and analyze the behavior of heterogeneously flagellated microswimmers in viscous fluids.
To investigate the influence of magnetic fields and fluid properties on microswimmer motility and diffusion.
To demonstrate controlled trajectory following and analyze propulsion mechanisms.

Main Methods:

Isolation and functionalization of Salmonella typhimurium flagella for attachment to microparticles.
Assembly of microswimmers and characterization of their velocity responses under varying magnetic field frequencies.
Mean square displacement analysis to quantify diffusive behavior.
Proportional feedback control for trajectory demonstration.

Main Results:

Assembled microswimmers exhibited anomalous diffusion at small time scales and increased diffusivity compared to non-rotating controls.
Flagellated microswimmers showed decreased diffusivity in Brownian conditions versus non-flagellated particles.
Microswimmers successfully followed selected trajectories with reasonable accuracy.
Propulsion was significantly influenced by magnetic field handedness, leading to frequency-induced reversals due to flagellar bundling.

Conclusions:

Heterogeneously flagellated microswimmers can be engineered for controlled motion in viscous fluids.
Magnetic field properties, specifically handedness, critically impact microswimmer propulsion dynamics.
The findings provide insights into microswimmer design and control for potential biomedical applications.