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by
  • Xing Zhou 1,
  • Zhenggui Li 1,2,* and
  • Zhichao Qing 1
  • et al.

Reviewer 1: Anonymous Reviewer 2: Anonymous Reviewer 3: Anonymous Reviewer 4: Anonymous

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript provides a valuable overview of mechanical micropumps and a new perspective on ferrofluid-based alternatives. The review is well supported with references and figures and covers a broad range of structural elements, fabrication methods, and applications, making it a useful resource for readers. However, I have several points of concern that, if addressed, would substantially enhance the paper's academic rigor and clarity.

  1. Mismatch Between Title and Scope
    The title, "Current Status and Future Development in the Field of Micropumps: A Review," suggests a broad survey of all major micropump types, including electrokinetic, thermal, and acoustic principles. In practice, the manuscript focuses almost exclusively on mechanical and ferrofluid micropumps, creating a noticeable gap between the title and the actual scope.
  2. Lack of In-depth Analysis on Trends and Challenges
    The discussion of mechanical micropumps is detailed but often descriptive rather than analytical. Issues such as high fabrication difficulty, high driving voltages, and short lifespans are mentioned, but their fundamental causes and persistence are not sufficiently explored.
  3. Comparison Framework
    The performance comparison between mechanical and ferrofluid micropumps is informative but difficult to interpret without normalization of parameters (e.g., flow rate per unit volume, pressure generation efficiency). A clearer benchmarking framework would significantly improve readability.
  4. Applications and Outlook
    The section on ferrofluid micropump applications highlights advantages but remains limited in critical insight. More discussion of barriers to clinical translation, industrial adoption, and reliability under real-world conditions would strengthen the outlook.

Overall, addressing these issues will improve the manuscript’s clarity, scope accuracy, and analytical depth, making it a stronger contribution to the field.

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

It is a nice work with wide view on the field. I do not miss anything to mention. The figures can be improved for being more informative. There are only small things I have noticed and they are mentioned below:  

Fig2 (f): It is impossible to read the text on it. Please rorganize this figure or at least add bigger text on.

Figure 7: At the middle maybe "Selecite" is a typo and it wanted to be "Selective" and the same for the bottom part: "Etching", it is better than "Etchine" that is there now.

The tables are very impressive but the widths of the columns should be changed th have the longest text to be in one line. For examplethe width of References can be lesser so the Type coulmn can be wider avoiding to have such things like 
"PE(PZT-
5A)" 
It can be than "PE(PZT-5A)"

The same also for Table 2 where sometimes the ")" sign onyl is forced in to a new line.

About Tables an other comment. It is better to have a table on one page instead of slicing it in to two (there is no header on the second part the reader maybe do not know what is what in the columns).

Last comment.
As a fun fact it can be mentioned that in the inkcartridges of the inkjet printers there are also piezo micropumps that pumps exatly the volume of the ink droplet used to print a "pixel" (in the older times there were microheaters, which produces micrububbles -this type of printers was called 'bubble jet'-  and these expanding bubbles were the pumps.
So everyone, who prints with such a device, uses a series of micropumps (without realizimg that).

 


 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Review of the paper

 

 Current Status and Future Development in the Field of Micro- pumps: A Review

 

The review includes an extended analysis of micropumps, namely mechanical micropumps, discussing their diaphragms, pump chambers, materials, and other aspects. The concept of ferrofluid-based micropumps is introduced by the authors, an outlook on their potential applications in biomedicine and specialized fields is provided.

The list of references contains 242 positions. The paper is quite fairly written in general and deserves to be published.

 

Some remarks and comments:

 

1) Fig. 2d, f. Fig. 3d. The letters are too tiny, they are unreadable. Please increase their size.

 

2) Fig. 5. The term “supply mode” looks not appropriate here, because its meaning slightly differs from the term “pump mode”

The reviewer believes that “suction mode” or “intake mode” would be better instead of “supply mode”.

 

3) Fig. 5 demonstrates some types of actuators. Their benefits and drawbacks should be also shown, preferably in a separate Table.

 

4) The references should be corrected, e.g. L. 240 “Lin YQ [101] proposed” and L. 241 “Nicola BA [102] developed” please replace by “Lin et al. [101] proposed” and “Nicola et al. [102] developed”. Please check such items throughout the paper.

 

5) Fig. 3 and Fig. 6 contain a lot of small pictures, but the principles on how do they work are not clearly presented. Some schematic diagrams showing the principles of work would look much better than the colorful pictures and even photographs having no clear demonstrations of the principle of their work.

Fig. 4 and Fig. 5 (in general) as well as Fig. 12 look much better!

 

6) Tables 1 - 3. I guess the column “Authors” should be removed, because the only one author is presented, and readers could find all the authors using list of references.

 

7) Please collect possible applications in a Table as well. E.g. in rows the types of pumps could be listed, and in columns their applications could be shown.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Overall, the review is good, but it still lacks several key elements that need to be added and explained/presented properly. I have the following major comments for improving the review. Once the comments are addressed, I am happy to accept the manuscript.

1) Authors need to explain each figure properly in the text. It is not sufficient to have just a caption of the figure, but to have no explanation in the manuscript text. Each figure/subfigure needs to be explained properly in the text. For most of the paper, there is no proper explanation of each figure.

2) See figure 2 (b) and figure 3(b). The text '(b)' is not visible properly. Again, Figures 2 and 3 are not properly explained in the text. Check all the figures for such errors.

3) I would like the authors to include more schematic figures drawn by the author for better understanding, in addition to the copyright figures from the literature. Please take a look at this review of droplet sorting and their approach to drawing schematics. (https://doi.org/10.1039/C6LC01435F )

4) Kindly review the groups that have worked on a lot of diaphragm and valve microfluidic devices. for e.g,

The authors missed the pioneering work done by the Quack group in their Science publications (https://doi.org/10.1126/science.288.5463.113 ) (https://doi.org/10.1126/science.1076996 ). Look for other work from the group. It is very important to cite and explain the first work done in the field. 

Abate and weitz group ( https://doi.org/10.1063/1.3431281 ) ( https://doi.org/10.1063/5.0064265 ) (https://doi.org/10.1063/1.3567093 ) ( https://doi.org/10.1063/1.2945797 )

Neild group (https://doi.org/10.1007/s10404-021-02487-y ) (https://doi.org/10.1016/j.snb.2019.04.115 ) (https://doi.org/10.1021/acs.langmuir.9b03515 ) 

Other groups ( https://doi.org/10.1016/j.snb.2011.09.051 ) ( https://doi.org/10.1016/S0925-4005(02)00468-9 ) (https://doi.org/10.1039/C1LC20251K ) 

5) I think it would be great to include droplet-based systems with such actuators, valves, and diaphragms.

6) Look at the following review papers in a similar field to include more work in the field (https://doi.org/10.34133/space.0008 ), (https://doi.org/10.1039/C6LC01435F ), ( https://doi.org/10.1063/5.0267868 ). Check the pneumatic valves section for the last two review papers.

7) At the end, it is very important to have an elaborate conclusion and an outlook section where different technologies are compared.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The revisions have been carried out very thoroughly. The responses are clear, the additional analyses are well organized, and the application section now provides a balanced view. Overall, the manuscript has been significantly improved and the comments have been addressed appropriately.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have addressed all concerns and the paper could be accepted in present form.

The only point to be improved during proof editing is the Figure 11 caption. It is now "ferrofluid", but this text is not clear enough. Please extend this caption.

Reviewer 4 Report

Comments and Suggestions for Authors

The authors have implemented the comments. I am happy to accept the manuscript.