The Bioactive Mg-Zn-Gd Wire Enhances Musculoskeletal Regeneration: An In Vitro Study

Round 1

Reviewer 1 Report

1.

The description of 2.1 is very rough. The authors should explain the detailed information about each data in Fig.1. In EDX, the readers could not understand which parts are Ga peaks. The reviewer thinks that only GaLα is detected for Ga. This EDX graph is too rough for "The element of magnesium, zinc and gadolinium were detected by EDS" in Line 68.　The labels of the x- and y-axis are lacking.

 

2.

In 2.2, the authors described some average values and standard deviations for the pH and concentrations. However, the digits are not aligned between AV and SD in pH, and the significant digits are unknown.

 

3.

In Figs.2A and 2B, the x-axis description is wrong. For example, spacing between "0" and "72h" is the same as between "168h" and "336h". If the authors prepare line charts, such notations are incorrect.

 

4.

In Fig.2C, why was the phosphorus detected? Please explain to help the readers understand.

 

5.

In Fig.3, please describe the statistical significance of each graph as possible. The reviewer thinks that the descriptions as "Days 3" and "Days 5" are correct instead of "Day 3" and "Day 5".

 

6.

In Fig.4: "AONVA" → "ANOVA."

 

7.

 

The definition of "bioactive" or "bioactivity" is unclear throughout the main text. Different meanings often define this term according to the research fields. Please explain the definition in this study.

Author Response

Dear reviewer, we really appreciate your comments and suggestions. We will response your comments and questions point by point.

1.The description of 2.1 is very rough. The authors should explain the detailed information about each data in Fig.1. In EDX, the readers could not understand which parts are Ga peaks. The reviewer thinks that only GaLα is detected for Ga. This EDX graph is too rough for "The element of magnesium, zinc and gadolinium were detected by EDS" in Line 68.　The labels of the x- and y-axis are lacking.

 

Response: sorry for the poor quality of the figure. It was scanned by an old system. We have re-do the scanning and updated the figure 1. We agreed with your point about the wave of Gd and we have highlight it in results (page 3, lines 135).

2. In 2.2, the authors described some average values and standard deviations for the pH and concentrations. However, the digits are not aligned between AV and SD in pH, and the significant digits are unknown.

 

Response: thank you for reminding. We have revised the pH value with AV and SD (page 3, lines 147). Also, we added the significant digitals in figure 2.

3. In Figs.2A and 2B, the x-axis description is wrong. For example, spacing between "0" and "72h" is the same as between "168h" and "336h". If the authors prepare line charts, such notations are incorrect.

 

Reponses: thank you for reminding. We have revised this mistake in figure 2.

 

4.In Fig.2C, why was the phosphorus detected? Please explain to help the readers understand.

 

Response: It is a very good question. Besides to the phosphorous, calcium and oxygen were also detected. After immersing in the culture medium or implanting into body, Mg degradation was triggered. Firstly, reacted with H₂O, Mg produced Mg(OH)₂ and hydrogen. Then, Mg(OH)₂ hydrolyzed into Mg²⁺ and OH^-. The OH^- could bond H₂PO₄^-/HPO₄^2-to PO₄^3-. Eventually, Mg²⁺ and PO₄^3- formatted Mg₃(PO4)₂. This process could explain the Mg, P, and O element on the corrosion interface detected by SEM/EDS. Of course, this matrix should be mixed compounds instead of pure Mg₃(PO4)_2. The content of the degradation products and their biological potential are meaningful to investigate in the future work. We presented the chemical reaction as figure 2A. Also, we added this part into discussion (page 9, lines 356).

 

5.In Fig.3, please describe the statistical significance of each graph as possible. The reviewer thinks that the descriptions as "Days 3" and "Days 5" are correct instead of "Day 3" and "Day 5".

 

Response: Thank you for reminding. We have revised the figure 3 accordingly.

 

6.In Fig.4: "AONVA" → "ANOVA."

 

Response: sorry for the mistake. We have revised it.

 

7.The definition of "bioactive" or "bioactivity" is unclear throughout the main text. Different meanings often define this term according to the research fields. Please explain the definition in this study.

 

Response: In this study, bioactive material could be defined as the machined or fabricated materials to release biological factors for enhancing healing effect. We have added the definition in introduction (page 2, lines 64).

 

Author Response File: Author Response.docx

Reviewer 2 Report

The information about the review report corresponding to Li et. al., the article entitled ‘The Magnesium Zinc Gadolinium wire applying for musculo-skeletal regeneration: biosafety, biodegradation, and bioactive performance’ are presented in detail by the author(s) on enhance the strength of the micromorphology, degradation, cytotoxicity, angiogenesis, and osteogenesis as a piolet study for the in vivo evaluation, as well as enabling the biocompatibility and bioactive as the material for muscle-skeleton repair. However, the author(s) should consider revising the manuscript and address the following points to further help the readers in easy understanding of the work.

-          ‘Title’ is too long not suitable in sense should be moderate as innovative research underlying unique features.

-          ‘Abstract’ not properly well written should have to polish and clearly mention the novelty of work differ from others simultaneously reported in comprehensive review. What is the unique in reported review article that should clear to the reader for the reason of suitable publication.

-          ‘Research and highlights’ should focus on main research outcomes 3-4 bullet points within 85 characters only, not more than that written.

-          ‘Graphical abstract’ is the most essential part of the manuscript which seems not enough informative as presented and only exclusive graphical diagram allowed.

-          All headings and subheadings (Italic) should assign numbers in the whole manuscript.

-          Not enough discussed in the ‘Introduction’ part, more generalized work needing to explore about generalized biomaterials and biomedical applications by citing  current references DOI’s given below;

DOI: https://doi.org/10.1016/j.nantod.2021.101137

DOI: https://doi.org/10.1016/j.bioactmat.2020.10.026

DOI: https://doi.org/10.1016/j.matlet.2021.130612

DOI: https://doi.org/10.1002/admi.202000819

DOI: https://doi.org/10.1038/s41598-019-55530-y

DOI: https://doi.org/10.1080/10408436.2021.1935717

DOI: https://doi.org/10.1016/j.bioactmat.2020.04.004

DOI: https://doi.org/10.1007/978-3-030-67223-2_5

DOI: https://doi.org/10.1016/j.bioactmat.2021.01.011

DOI: https://doi.org/10.1166/jbmb.2017.1708

-          Experimental sec. Should be divided into ‘Materials and methodology’ and ‘Spectroscopy and microscopic investigations should be imported informative schematics, which may explore thematic research work presentation as well as a chemical reaction mechanism too, which are missing entire manuscript.

-          The author explored in Fig 1, the FE-SEM patterns which is very informative images and magnification scale should be manually plot, remove instrument generated scale. The nanostructures formation which proper exploration and surface topology via AFM analysis required to mention. Each and heading section should import informative morphological images with proper illustration highly suggested.

-          Why set that Zn²⁺ concentrations 99 from 0.001 mM to 0.1 mM presented

-          What’s the role of Gd³⁺ and it kept the cell viability higher than 75% at all the time points

-          ‘Conclusion’ section should polishing with the advantages of novelty applications and comparative analysis of simultaneous reported work main research outcomes as well as potential applications and industrial aspects.

-          Insufficiency of references for this article should pay attention by the authors above suggested.

As it stands, manuscript seems lack of presentation skills in an organized manner, and almost images needing to reorganize as per illustration in the text, as well as overall proof reading is highly required to avoid typos and grammatical mistakes as per suggested above. The last chance author should given further careful revision as suggested and pin-point answering therefore, recommendation ‘Major Revision’ is mandatory further acceptance as per journal standard.

Author Response

Point-by-Point Response

Dear reviewer, we really appreciate your comments and suggestions. We will response your comments and questions point by point.

1. Title’ is too long not suitable in sense should be moderate as innovative research underlying unique features.

 

Response: Thank you for the suggestion. We have revise it as “The bioactive Mg-Zn-Gd wire enhances musculoskeletal regeneration: an in vitro study”.

 

2. ‘Abstract’ not properly well written should have to polish and clearly mention the novelty of work differ from others simultaneously reported in comprehensive review. What is the unique in reported review article that should clear to the reader for the reason of suitable publication.

-          ‘Research and highlights’ should focus on main research outcomes 3-4 bullet points within 85 characters only, not more than that written.

-          ‘Graphical abstract’ is the most essential part of the manuscript which seems not enough informative as presented and only exclusive graphical diagram allowed.

-          All headings and subheadings (Italic) should assign numbers in the whole manuscript.

 

Response: That is a very useful suggestion. We polished the abstract and added the research and highlights as well as a graphical abstract.

      

3. Not enough discussed in the ‘Introduction’ part, more generalized work needing to explore about generalized biomaterials and biomedical applications by citing  current references DOI’s given below;

DOI: https://doi.org/10.1016/j.nantod.2021.101137 

DOI: https://doi.org/10.1016/j.bioactmat.2020.10.026 

DOI: https://doi.org/10.1016/j.matlet.2021.130612 

DOI: https://doi.org/10.1002/admi.202000819 

DOI: https://doi.org/10.1038/s41598-019-55530-y 

DOI: https://doi.org/10.1080/10408436.2021.1935717 

DOI: https://doi.org/10.1016/j.bioactmat.2020.04.004 

DOI: https://doi.org/10.1007/978-3-030-67223-2_5 

DOI: https://doi.org/10.1016/j.bioactmat.2021.01.011 

DOI: https://doi.org/10.1166/jbmb.201R7.1708

 

Response: Thanks for your recommendation. We have carefully read these studies and cited in the introduction part properly.

 

4. Experimental sec. Should be divided into ‘Materials and methodology’ and ‘Spectroscopy and microscopic investigations should be imported informative schematics, which may explore thematic research work presentation as well as a chemical reaction mechanism too, which are missing entire manuscript.

 

Response: Thanks for your constructive suggestion. We have re-organize the structure of Methods and Materials which was divided into “material preparation”, “degradation and cytotoxicity”, and “spectroscopy and microscopic investigations”. In addition, we added chemical degradation in figure 2A. To demonstrate the process of wire fabrication, we added figure 7 to show the industrial flow.

 

5. The author explored in Fig 1, the FE-SEM patterns which is very informative images and magnification scale should be manually plot, remove instrument generated scale. The nanostructures formation which proper exploration and surface topology via AFM analysis required to mention. Each and heading section should import informative morphological images with proper illustration highly suggested.

 

Response: sorry for the poor quality of the figure. It was scanned by an old system. We have re-do the scanning and updated the figure 1. As for AFM analysis, we did not do this test mainly because the wire will be implanted into tissue by catheter guidance or drilling holes. The surface topology will not affect the implanting process. Also, the wire will start to degrade right after implantation, the surface topology will change dynamically. Nevertheless, it is an important test for material R&D. We have listed it as a major limitation (Page 9, lines 383). Thank you for the suggestion which can definitely benefit our work in the future.

 

6. Why set that Zn²⁺concentrations from 0.001 mM to 0.1 mM presented

 

Response: the average concentration of Zn ions in metal extracts should be 0.08mM. Thus, 10% diluted extracts should be around 0.008mM, and 50% diluted extracts was around 0.04mM. The setting concentration range can cover all dilution situation. Also, the concentration of metal extracts usually presented relatively large SD. The relatively large dosage window could better reflect the concentration of each sample.

 

7. What’s the role of Gd³⁺ and it kept the cell viability higher than 75% at all the time points

 

Response: Adding Gd into Mg alloys could enhance the formability of material. Gd was used in clinical as the contrast medium for MRI. It might potentially affect local bone metabolism. Thus, we need to test if the Gd ions presented cytotoxic. Because of the low Wt% in the alloy, the Gd concentration was quite low in extracts, which kept the cell viability higher than 75% (low toxic level according to ISO 10993) at all the time points.

 

8. Conclusion’ section should polishing with the advantages of novelty applications and comparative analysis of simultaneous reported work main research outcomes as well as potential applications and industrial aspects.

 

Response: Thanks for the suggestion, we have polished the conclusion (Page 9, lines 389). We also added figure 6 to show the potential translation in musculoskeletal regeneration.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

At the stage of the editing process, please check the grammatical, spelling, and figures errors thoroughly.

Author Response

Thanks for your comments. We have revised the grammatical, spelling, and figures errors.

Reviewer 2 Report

Authors attained all necessary comments of the concern reviewers in revised manuscript, therefore final recommendation goes to 'Accept' for publication as per journal standard.

Author Response

Thank you for your comments.