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

Potential Due to a Magnetized Object01:24

Potential Due to a Magnetized Object

Magnetic dipoles in magnetic materials are aligned when placed under an external magnetic field. For paramagnets and ferromagnets, dipole alignment occurs in the direction of the magnetic field. However, the dipoles align opposite to the field in the case of diamagnets. This state of magnetic polarization due to the external field is called magnetization. Magnetization is defined as the dipole moment per unit volume. It plays a similar role to polarization in electrostatics.
The vector...
Atomic Nuclei: Nuclear Magnetic Moment00:59

Atomic Nuclei: Nuclear Magnetic Moment

All atomic nuclei are positively charged. When they have a nonzero spin, they behave like rotating charges. As a consequence of their charge and spin, these nuclei generate a magnetic field (B). This, in turn, gives rise to a magnetic moment (μ), which is randomly oriented in the absence of an external magnetic field. When an external magnetic field (B0) is applied, the magnetic moment vectors can align with the field or against it in 2 + 1 orientations. A hydrogen nucleus, which is just a...
Magnetic Field Lines01:19

Magnetic Field Lines

The representation of magnetic fields by magnetic field lines is very useful in visualizing the strength and direction of the magnetic field. Each of the magnetic field lines forms a closed loop. The field lines emerge from the north pole (N), loop around to the south pole (S), and continue through the bar magnet back to the north pole.
Magnetic field lines follow several hard-and-fast rules:
Diamagnetism01:26

Diamagnetism

Materials consisting of paired electrons have zero net magnetic moments. However, when these materials are placed under an external magnetic field, the moments opposite to the field are induced. Such materials are called diamagnets. Diamagnetism is the response of the diamagnets when placed in an external magnetic field.
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets.
Atomic Nuclei: Magnetic Resonance01:05

Atomic Nuclei: Magnetic Resonance

The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
Paramagnetism01:30

Paramagnetism

Paramagnets are materials with unpaired electrons that possess a finite magnetic moment. In the absence of a magnetic field, these moments are randomly oriented, and thus the net moment is zero. Under an external field, a torque acting on the moments tends to align them along the field's direction. However, the random thermal motion of electrons produces a torque opposite to the external field and tries to disorient the moments. These two competing effects align only a few moments along the...

You might also read

Related Articles

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

Sort by
Same author

Gram-scale synthesis of high-loading single-atom Ni catalysts anchored on vinylene-linked covalent organic frameworks for efficient photocatalytic carbon dioxide reduction.

Journal of colloid and interface science·2026
Same author

Decontamination of volatile compounds from post-consumer recycled HDPE via supercritical CO<sub>2</sub>: Unravelling the critical role of co-solvent molecular structure.

Waste management (New York, N.Y.)·2026
Same author

Reticular Synthesis of Covalent Organic Frameworks with kgd-v Topology and Trirhombic Pores.

Journal of the American Chemical Society·2025
Same author

Imidazopyridinium-Linked Covalent Organic Frameworks for Efficient Gold Recovery.

Small methods·2024
Same author

Light-Promoted Extraction of Precious Metals Using a Porphyrin-Integrated One-Dimensional Covalent Organic Framework.

Angewandte Chemie (International ed. in English)·2024
Same author

Restricted Growth of Vinylene-Linked Covalent Organic Frameworks along Two-Dimensional Plane Using Heterogeneous Catalysis.

Journal of the American Chemical Society·2024
Same journal

Controlled Secondary Growth of CAU-1-NH<sub>2</sub> Membranes with Improved CO<sub>2</sub> Separation Performance.

Langmuir : the ACS journal of surfaces and colloids·2026
Same journal

Facile Fabrication and Stable Mechanism of a Microscale Heavy Calcium Carbonate Suspension.

Langmuir : the ACS journal of surfaces and colloids·2026
Same journal

Polycationic Biocidal Coatings: The Mechanism of Their Interaction with Cells.

Langmuir : the ACS journal of surfaces and colloids·2026
Same journal

Atomic-Scale Displacement in Ordered SmMnO<sub>3</sub> Nanoislands.

Langmuir : the ACS journal of surfaces and colloids·2026
Same journal

Vacancy Defect Modulated Interfacial Thermal Transport and Phonon Localization in AlGaN/GaN Heterojunctions.

Langmuir : the ACS journal of surfaces and colloids·2026
Same journal

Immobilization of Ytterbium via Polyphenol Chemistry on Implant Materials for Enhanced Cytocompatibility and Antibacterial Properties.

Langmuir : the ACS journal of surfaces and colloids·2026
See all related articles

Related Experiment Video

Updated: Jun 16, 2026

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains
07:42

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains

Published on: July 20, 2022

The visualized polarity-sensitive magnetic nanoparticles.

Tian-Long Zhang1, Bao-Hang Han

  • 1National Center for Nanoscience and Technology, Beijing 100190, China.

Langmuir : the ACS Journal of Surfaces and Colloids
|February 11, 2010
PubMed
Summary
This summary is machine-generated.

Researchers developed novel polarity-sensitive iron oxide nanoparticles (Fe(3)O(4) NPs) using functional organic molecules. These dual-functional nanomaterials act as visualized polarity sensors while retaining their superparamagnetic properties.

More Related Videos

Frequency Mixing Magnetic Detection Scanner for Imaging Magnetic Particles in Planar Samples
07:01

Frequency Mixing Magnetic Detection Scanner for Imaging Magnetic Particles in Planar Samples

Published on: June 9, 2016

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles
08:26

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles

Published on: October 19, 2015

Related Experiment Videos

Last Updated: Jun 16, 2026

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains
07:42

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains

Published on: July 20, 2022

Frequency Mixing Magnetic Detection Scanner for Imaging Magnetic Particles in Planar Samples
07:01

Frequency Mixing Magnetic Detection Scanner for Imaging Magnetic Particles in Planar Samples

Published on: June 9, 2016

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles
08:26

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles

Published on: October 19, 2015

Area of Science:

  • Materials Science
  • Nanotechnology
  • Organic Chemistry

Background:

  • Superparamagnetic iron oxide nanoparticles (Fe(3)O(4) NPs) are widely used in biomedical applications.
  • Developing nanomaterials with tunable optical properties is crucial for advanced sensing applications.
  • Functionalizing nanoparticles with organic molecules offers a versatile approach to impart new properties.

Purpose of the Study:

  • To design and synthesize novel polarity-sensitive organic molecules for functionalizing Fe(3)O(4) NPs.
  • To prepare Fe(3)O(4) NPs with dual functionality: polarity sensing and superparamagnetism.
  • To investigate the efficiency of different organic molecules in passivating and functionalizing the nanoparticle surface.

Main Methods:

  • Ligand exchange strategy was employed to functionalize Fe(3)O(4) NPs with designed organic molecules (DIAA, DIUA, DISA).
  • Carboxyl groups were utilized as universal coordinating sites for binding molecules onto the NP surface.
  • Fluorescence emission properties of the functionalized NPs were analyzed in solvents of varying polarities.

Main Results:

  • Three polarity-sensitive organic molecules (DIAA, DIUA, DISA) were successfully synthesized and used to functionalize Fe(3)O(4) NPs.
  • DISA molecules, with two carboxyl groups, demonstrated superior surface passivation and solubility.
  • DISA-functionalized Fe(3)O(4) NPs exhibited distinct fluorescence emissions across different solvent polarities, preserving superparamagnetic properties.

Conclusions:

  • The study successfully prepared dual-functional, polarity-sensitive Fe(3)O(4) NPs.
  • These NPs can serve as visualized polarity sensors, retaining their magnetic properties.
  • This work provides a conceptual framework for designing multifunctional, polarity-sensitive nanomaterials.