A Comparative Study of the Electro-Assisted Grafting of Mono- and Bi-Phosphonic Acids on Nitinol
, Corentin Libioulle 1, Tatiana Issakova 1, Laetitia Mespouille 2, Philippe Dubois 2, Joseph Delhalle 1 and Zineb Mekhalif 1,*Round 1
Reviewer 1 Report
A series of methods were used to characterize the modified substrates. The superiority of EG process was confirmed. Considering the characterization results of 3 organic molecules by EG process, XPS (Table 1) showed that MIP2 and HEP2 gave a higher P/NiTi ratio than C1P, but the surface layer resistance (Table 2) and the electrochemical impendence (Fig. 7) of C1P are higher than MIP2. Why?
Author Response
Dear editor,
First, we would like to thank the reviewers for the comments about our paper. You will find hereunder the modifications we made to our article, as well as our answers to the reviewers.
Reviewer 1:
« A series of methods were used to characterize the modified substrates. The superiority of EG process was confirmed. Considering the characterization results of 3 organic molecules by EG process, XPS (Table 1) showed that MIP2 and HEP2 gave a higher P/NiTi ratio than C1P, but the surface layer resistance (Table 2) and the electrochemical impendence (Fig. 7) of C1P are higher than MIP2. Why?»
After considering your comment, and checking the mentionned results, we believe that there is no significant difference between C1P, MIP2 and HEP2 as such. However, the point we would like to underline is the improvement of the layer resistance through the electro-assisted process
Looking to read from you and hoping that with the present revision, the paper will get a final positive answer,
Sincerely yours,
Zineb Mekhalif
Author Response File: 
Author Response.doc
Reviewer 2 Report
Dear Authors,
I read your manuscript with great interest. He undertakes topics that are relevant and current. The article describes well the planning, implementation and interpretation of research results, is well prepared for publication. Below are some comments that may be helpful in editing the final version of the work.
Keywords:
I think that keyword: "mono- and bisphosphonic acid derivatives" is not a good idea. There is not a single article in MDPI publishing house that uses this phrase as a keyword.
Line 59: What do you mean by "exploratory"? Maybe the word "experimental" would be better? Or maybe "research" or "investigation"?
Lines 123, 126 and 139: add references for formulas.
Line 131: The abbreviation EIS is not explained before.
Line 216: The abbreviation CV was previously explained (line 101).
Figure 4. The figure shows the results with error bars. What error measure do these bars show?
Figure 5: Some subtitles may not be legible (readable) because they are too small.
Conclusions:
In the first sentence, I advise you to add information that the surface of the NITINOL alloy has been modified.
In the last sentence, please add quantitative information. "Slight" is too general.
References: The literature sources are well-chosen, they are diverse and current. I think that for better recognition of the article you should add references from MDPI journals.
Author Response
Reviewer 2:
« I read your manuscript with great interest. He undertakes topics that are relevant and current. The article describes well the planning, implementation and interpretation of research results, is well prepared for publication. Below are some comments that may be helpful in editing the final version of the work. »
We thank you for your appreciation and for your relevant comments.
« I think that keyword: "mono- and bisphosphonic acid derivatives" is not a good idea. There is not a single article in MDPI publishing house that uses this phrase as a keyword.»
Even though the keyword “bisphosphonic” is well known in the literature, we agree that the keyword “monophosphonic” is rather absent. However, we believe that these are the most understandable terms for a comparison purpose.
«Line 59: What do you mean by "exploratory"? Maybe the word "experimental" would be better? Or maybe "research" or "investigation"?»
“Exploratory” has been replaced by “experimental”.
«Lines 123, 126 and 139: add references for formulas. »
References has been added.
«Line 131: The abbreviation EIS is not explained before. »
«Line 216: The abbreviation CV was previously explained (line 101). »
Those have been corrected.
«Figure 4. The figure shows the results with error bars. What error measure do these bars show? »
As explained in the experimental section (lines 102-104), “To assess the reproducibility of experiments, all analyses are performed in triplicate. In the case of XPS characterizations, each sample is also analyzed at three different locations”. The error bars results from these tripilicates.
«Figure 5: Some subtitles may not be legible (readable) because they are too small. »
The font size has been increased.
«Conclusions:
In the first sentence, I advise you to add information that the surface of the NITINOL alloy has been modified. »
The sentence has been modified into “Nitinol alloy has been modified by conventional (CG) and electro-assisted (EG) grafting of three organophosphonic derivatives (C1P, MIP2 and HEP2) with one or two anchoring groups have been compared.“
In the last sentence, please add quantitative information. "Slight" is too general. »
The sentence has been modified into “By contrast, the conventional grafting (CG) leads to a decreased corrosion resistance with jcorr up to three times higher and up to twice more Ni surface content ”
«References: The literature sources are well-chosen, they are diverse and current. I think that for better recognition of the article you should add references from MDPI journals. »
The following references have been added.
[13] M. Nematollahi, K.S. Baghbaderani, A. Amerinatanzi, Application of NiTi in Assistive and Rehabilitation Devices : A Review, (2019).
[14] N. Eliaz, Corrosion of Metallic Biomaterials : A Review, (2019). doi:10.3390/ma12030407.
Looking to read from you and hoping that with the present revision, the paper will get a final positive answer,
Sincerely yours,
Zineb Mekhalif
Reviewer 3 Report
This is surely an interesting and original work with the potential to be published in Surfaces. I have only a couple of comments that the authors should implement into the revised manuscript prior to publication. 1) Introduction - The connection between the aim of the work and the literature gaps should be more extensively described, thus better clarifying the novelty of this contribution. 2) Conclusions - The practical impact of the results obtained in this work should be better highlighted. The authors should also give an outlook on future research work.Author Response
Reviewer 3:
« This is surely an interesting and original work with the potential to be published in Surfaces. I have only a couple of comments that the authors should implement into the revised manuscript prior to publication. »
We thank you for your appreciation and for your relevant comments.
« 1) Introduction - The connection between the aim of the work and the literature gaps should be more extensively described, thus better clarifying the novelty of this contribution. »
As explained in the introduction (lines 56-61), the most common modification process used nowadays to improve the organisation of bulky molecules in SAMs is the elaboration of mixed monolayers. Our work investigates an alternative way by grafting larger anchoring groups, which lead to an efficient protective layer with available space at the end the chains to incorporate larger groups.
«2) Conclusions - The practical impact of the results obtained in this work should be better highlighted. The authors should also give an outlook on future research work. »
The conclusion has been modified with the addition of: “The (electro)grafting of bisphopshonic acid derivatives thus appear to be a promising alternative to mixed monolayers, which were previously used for the grafting of bulky polymerization initiators.[43] In this context, a monolayer made of an polymerization initiating specie deriving from HEP2 or MIP2 is to be investigated.”
Looking to read from you and hoping that with the present revision, the paper will get a final positive answer,
Sincerely yours,
Zineb Mekhalif
