Many people are studying the heating responses of magnetic nanoparticles in alternating magnetic field (AMF) environments to evaluate their suitability for a range of applications.
However, these studies could be failing to capture vital information, primarily due to a lack of capability in the basic induction heaters that they are using. These conventional induction heaters are designed specifically to heat metal components – this means that they have a very limited frequency range.
Frequency Response Profiles
At Nanotherics, we are often asked why we offer ten frequencies as standard in our magnetic nanoparticle heating equipment, when many publications simply show one or two.
Subjecting particles to as many frequencies as possible, across as wide a range as possible, is absolutely essential to get a complete picture of the properties of a nanoparticle sample. This full picture allows the suitability of the particles for a particular application to be properly assessed.
Using a single frequency will only provide a snapshot, and not a full Frequency Response Profile (FRP).
Figure 1. Hyperthermia data comparing the frequency dependence for different nanocrystal morphologies (22 nm spheres, polymorphous nanocrystals, and 55 × 2 nm wires). Ref: Iron Leisha M. Armijo et al., 2012. Oxide Nanocrystals for Magnetic Hyperthermia Applications. Nanomaterials 2012, 2, 134-146
As can clearly be seen from the data above, particles of different sizes and shapes will respond very differently at different frequencies and field strengths. Researchers will not see the full and complete picture if they can only analyze their particles using frequencies of between 150 kHz and 450 kHz, for example (a very common frequency range capability for induction heaters). Using a wider range of frequencies allows a full Frequency Response Profile to be built.
MagneTherm™ from Nanotherics
MagneTherm™ offers ten frequencies as standard from 100 kHz to 1MHz. The system is capable of frequencies as low as 50 KHz, and can provide up to 25 individual frequencies, if all options are included. This provides the most comprehensive range of applicable and relevant frequencies of any induction heating system available.
The magneTherm has been designed specifically for nanoparticle heating applications, operating at a wide range of frequencies (from 100 kHz to 1MHz) with field strengths up to 20 kA/m (25 mT), in one complete system. Since the heating capacity of magnetic nanoparticles will vary, depending on size, shape and material properties, it is critical to be able to evaluate heating capacity (SAR/SLP/ILP) over as broad a range of frequencies as possible.
This information has been sourced, reviewed and adapted from materials provided by nanoTherics.
For more information on this source, please visit nanoTherics.