Which grade should I choose — oil-based or water-based?

Choose by system, not by price. Choose oil-based (light hydrocarbon carrier) when the carrier must not evaporate, must not mix with other media, or when low viscosity similar to water is needed. Choose water-based (deionized water carrier) when the carrier may evaporate, or when magnetic particles must be introduced into an aqueous system such as magnetic beads for in-vitro diagnostics. Choose dry powder when you need to disperse the particles into your own solvent.

Can ferrofluid be used in the human body or for therapy?

No. Ferrotec states that its ferrofluids are not FDA-approved for in-vivo testing or therapy in humans, and the products are currently recommended for research use only. For biomedical directions we supply R&D and in-vitro diagnostic development use only — not clinical or in-vivo applications.

FERROFLUID FOR RESEARCH · SHIPS WORLDWIDE

Ferrotec EMG Series Ferrofluids
26 grades, one source

Q: What is the minimum order quantity and lead time?

Standard grades start at 10 mL — there is no need to buy a full batch for a research trial. Bulk quantities are priced per liter. In-stock grades typically ship in 3-5 business days; non-stock grades follow the Ferrotec channel lead time, which we confirm in writing before order.

Q: Do you provide MSDS and analytical data?

Yes. We provide MSDS/SDS, batch numbers and measured data such as saturation magnetization. Batch numbers are traceable. For export orders we can prepare commercial invoice and packing list documents.

Oil-based, water-based and dry magnetic nanoparticle powder — 26 standard grades from a single supplier. Particles are approximately 10 nm, single-domain and truly superparamagnetic, so they do not settle. We support magnetic domain observation, sensors and valves, in-vitro diagnostics and biomedical research, and material separation. Free selection support from an engineer who works with your setup.

Get Selection Support View All 26 Grades

~10 nm · Single-domain From 10 mL Batch traceable · MSDS Worldwide shipping

WHAT IS FERROFLUID

Ferrofluid is not simply "a magnetic liquid" — it is a magnet that flows

A ferrofluid is a stable colloidal suspension: magnetic nanoparticles coated with a surfactant and dispersed in a carrier liquid. Because the particles are nanosized and single-domain, Brownian motion overcomes gravity — the fluid does not settle, and when the field is removed it shows no remanence and no hysteresis. That is what allows it to be injected into gaps only tens of micrometres wide, and to seal around a rotating shaft without wearing it.

It is important to distinguish ferrofluid from other magnetic materials that are often confused with it. Choosing the wrong one wastes a project.

Material	Particle scale	Magnetic behaviour and typical use
Ferrofluid What we supply	Nanoscale (~10 nm)	No settling, no remanence, no hysteresis. Can be injected into very small gaps. Used for magnetic domain observation, sensing, damping, magnetic separation and biomedical research. Weak force transmission.
Magnetorheological fluid (MRF)	Micron iron powder	Field-induced yield stress of 50–100 kPa — transmits high torque but does settle. Used in dampers, suspensions, clutches and polishing. Not our product.
Ferrite / NdFeB powder	Micron to millimetre	Solid magnetic material for pressed magnets and magnetic plastics. Cannot flow.
Magnetorheological elastomer (MRE)	Micron particles in polymer matrix	Solid, but stiffness changes with field. Used for tunable-stiffness mounts. Not a liquid.

THREE CARRIERS

Choose by carrier, not by price

Every EMG grade belongs to one of three carriers. Which carrier you need is usually determined by your experiment, not by the magnetic strength.

Oil-based — 5 grades

Light hydrocarbon carrier. Choose this when the carrier must not evaporate, must not mix with the surrounding medium, or when you need a low viscosity. Grades EMG 900 / 901 / 905 / 909 / 911, Ms from 11 to 99 mT.

Water-based — 17 grades

Deionized water carrier. Choose this when the carrier may evaporate, or when magnetic particles must be introduced into an aqueous system — for example magnetic beads for in-vitro diagnostics. Note the "P" suffix indicates a different surfactant system.

Dry powder — 4 grades

Carrier-free magnetic nanoparticles. Choose this when you need to disperse the particles into your own solvent or polymer. EMG 1200 / 1300M / 1400 / 1500 with fatty-acid, polymer, hydrophobic and polar coatings.

Not sure which one?

Tell us the medium you are working in, the field strength available, and what you need the fluid to do. We will tell you which carrier and which Ms range to start from — and if ferrofluid is the wrong material for your application, we will say so.

GRADE OVERVIEW

The three carriers, at a glance

Series	Grades	Saturation magnetization (Gs)	Typical starting point
Oil-based	EMG 900 / 901 / 905 / 909 / 911	110 – 990	Highest magnetic response in the range; EMG 900 is the strongest at 99 mT
Water-based	17 grades with optional P suffix	33 – 440	Most work happens in the 110–220 Gs band
Dry powder	EMG 1200 / 1300M / 1400 / 1500	—	Dispersed into your own solvent; four coating types

Full parameter tables — viscosity, density, pour point, flash point and initial susceptibility — are on the Products page. Original Ferrotec datasheets and MSDS are available on request.

See full specifications for all 26 grades

APPLICATIONS

Where ferrofluid is actually used

Ferrotec lists six application directions for the EMG series. These are the ones we support most often.

Magnetic domain observationThe classic laboratory use. A thin ferrofluid layer makes domain walls on a polished sample visible under an optical microscope.

Sensors, switches and valvesSealing, damping and actuation in small gaps where a conventional seal would leak or wear.

In-vitro diagnostics and biomedical researchMagnetic beads and particle handling for assay development. Research and IVD development only — not for in-vivo use.

Material separationDensity-based separation of non-magnetic materials in a paramagnetic medium.

Metal crystallization and fracture analysisRevealing grain structure and crack paths on metal surfaces.

Carbon nanotube growthCatalyst particle placement in CNT synthesis.

Compliance note: Ferrotec states its ferrofluids are not FDA-approved for in-vivo testing or therapy in humans and are currently recommended for research use only. We therefore supply the biomedical direction for R&D and in-vitro diagnostic development only. Water-based grades should be used within about three months of delivery because the particles tend to agglomerate over time.

WHY WORK WITH US

A supplier who will tell you when you do not need the product

Selection support, not just a price list

Tell us your medium, your available field and your goal. We will recommend a carrier and an Ms range from the 26 grades — or tell you that ferrofluid is not the right material. Getting this wrong costs you months, not dollars.

Small quantities for real experiments

Standard grades start at 10 mL. You do not have to commit to a full batch to find out whether a grade works in your setup.

Traceable documentation

Batch numbers, saturation magnetization data and MSDS are supplied. If a result needs to be reproduced a year later, you can trace the exact batch.

Ships worldwide from Shenzhen

We ship to research institutions and companies worldwide, and assist with the export documents including commercial invoice and packing list.

FAQ

Questions researchers ask us

What is the difference between ferrofluid and magnetorheological fluid (MRF)?

Ferrofluid contains nanoparticles of about 10 nm, which are single-domain and stay suspended by Brownian motion — it does not settle, and shows no remanence and no hysteresis. MRF contains micron-sized iron particles that do settle, but can transmit high torque with a yield stress of 50–100 kPa. They are not interchangeable. We supply ferrofluid, not MRF.

Oil-based or water-based — how do I choose?

Choose by system, not by price. Oil-based when the carrier must not evaporate, must not mix with other media, or when you need low viscosity. Water-based when the carrier may evaporate, or when particles must go into an aqueous system such as IVD magnetic beads. Dry powder when you will disperse the particles into your own solvent.

How do I choose the saturation magnetization (Ms)?

Ms determines how strongly the fluid is pulled in a field, expressed in gauss (Gs) or millitesla (mT). Choose high Ms (EMG 900, 990 Gs / 99 mT) when you need the droplet held firmly in a gap; choose low Ms (EMG 911, 110 Gs) when magnetic response matters less and you want lower viscosity and lower particle loading. High Ms generally means higher viscosity and higher particle concentration.

What is the minimum order quantity and lead time?

Standard grades start at 10 mL, so there is no need to buy a full batch for a research trial. Bulk quantities are priced per litre. In-stock grades typically ship within 3–5 business days; non-stock grades follow the Ferrotec channel lead time, which we confirm in writing before you order.

Can you provide MSDS and analytical data?

Yes — MSDS/SDS, batch numbers and measured data such as saturation magnetization. Batch numbers are traceable. For export orders we can prepare commercial invoice and packing list documents.

Can ferrofluid be used inside the human body or for therapy?

No. Ferrotec states that its ferrofluids are not FDA-approved for in-vivo testing or therapy in humans, and the products are currently recommended for research use only. We supply the biomedical direction for R&D and in-vitro diagnostic development only.

Do you ship worldwide?

Yes. We ship from Shenzhen, China to research institutions and companies worldwide, and assist with the export documentation required.

Ferrotec EMG Series Ferrofluids26 grades, one source