Review Reports

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript by Skumiel, entitled “Comparison of 2- and 3-phase devices generating a rotating magnetic field for magnetic hyperthermia applications”, presents a relevant proposal by comparing two-phase and three-phase systems for generating rotating magnetic fields applied to magnetic hyperthermia. The study is timely, given the growing interest in optimizing low-cost and high-efficiency devices for biomedical applications.

However, I consider that important points need to be revised by the authors.

Points that must be addressed by the authors

1. I consider that the motivational part of the work needs to be improved, as it is very generic, without conveying to the future reader the real importance of the magnetic hyperthermia technique.
2. In the introduction, it is necessary to address aspects of the safety parameters for biological use, such as the limits of the magnetic field and the oscillation frequency, since these values can later be discussed in the discussion section.
3. We know that the coils normally used in magnetic hyperthermia equipment have significant efficacy in in vitro and animal model studies, but when we think about application in humans the efficacy is minimal. Therefore, I consider it important that this limitation be included in the introduction, and in the discussion it could be addressed how the coil presented could positively contribute to overcoming this limitation of the technique.
4. As mentioned in the previous item, the manuscript focuses on electrical and magnetic parameters, but the direct relationship with the efficacy of hyperthermia in biological systems is not well established. It is necessary to discuss how the results translate into real clinical applications.
5. The selection of 100 kHz as a fixed frequency needs to be better justified. What are the implications of this choice compared to higher frequencies, which are found in other studies in the literature?
6. Although the author highlights the low cost, there is no quantitative analysis of possible negative effects of residual harmonics on the results, especially regarding field stability. This important point must be discussed.
7. A broader discussion is needed about devices that use sinusoidal amplifiers in comparison with the proposed ones, since they are the standard in magnetic hyperthermia research.
8. It would be interesting to perform a test with magnetic nanoparticles, even a basic one, because the absence of this experiment limits the practical relevance of the conclusions.
9. The explanation of the nonlinearity observed in the graphs (Fig. 13) is superficial. It is necessary to better detail how the properties of ferrite affect the performance of the systems.
10. The comparison between two-phase and three-phase systems was carried out with coils of different numbers of turns, which may introduce bias. This needs to be discussed as a relevant limitation or addressed in another way in this comparison.
11. Regarding the data presented on the extremely low coupling values (0.0165 and 0.00222), they are not sufficiently commented on. What is the practical relevance of this to system efficiency? The authors could even bring data from the literature to discuss this aspect.
12. There is no analysis of how the systems could be scaled up for real applications in tumor hyperthermia (e.g., sample volume, field penetration, homogeneous heating). As already mentioned above, this aspect needs to be addressed in the discussion.

Author Response

Please check the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The investigation reported in this work is well described. The paper is well written and contains enough references to be followed easily. I have some observations, however, needing of the author’s response:
1. The author has published other works on the subject of rotating magnetic fields, but it is nowhere clear in this manuscript what are the progress and advances over previous works.

2. Fig. 2. Please specify in the caption the pertinent information on scales (amplitudes, frequencies) and the parameters (Cs,Ls, etc) used. The same applies to Fig. 6 and in general to all Figures containing plots or oscilloscope graphs 

3. The values of the field amplitudes and frequencies accessible are not clearly stated.

Author Response

Please check the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

My comments are included in the attached file.

Comments for author File: Comments.pdf

Author Response

Please check the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

I consider that all the requested points have been duly addressed, and therefore, I recommend the publication of the manuscript in its current form.

Reviewer 3 Report

Comments and Suggestions for Authors

Authors have addressed all of my comments. The manuscript can be published in it's present form.