Aqueous Synthesis of the Tiopronin-Capped Gold Nanoclusters/Nanoparticles with Precise Size Control via Deprotonation of the Ligand

Round 1

Reviewer 1 Report

Aqueous synthesis of tiopronin-capped gold nanoclusters/nanoparticles with precise size control via deprotonation of the ligand

This paper report that the synthesis of tiopronin-capped gold nanoclusters/nanoparticles an aqueous with precise size control, by exploiting the deprotonation of the ligand.

The manuscript is good which will be good addition in the literature however, there are few queries which need to be addressed as;

1.      Merits of the present study should be compared with the literature (specially with the latest study).

2.      Atleast one more characterization should performed (e.g. XRD).

3.      Correlation between results through different characterization should be highlighted.

4.      English and grammatical mistakes should carefully be examined again

5.      In addition to the above mention references, few more recent/relevant references may be cited as;

                    i.            https://pubs.acs.org/doi/10.1021/ja076333e

                  ii.            https://www.tandfonline.com/doi/full/10.1080/24701556.2020.1808680

                iii.            http://www.ijnnonline.net/&url=http:/www.ijnnonline.net/article_24532.html

                iv.            https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/chem.202103736

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

Kang et al., submitted the manuscript entitled “Aqueous synthesis of tiopronin-capped gold nanoclusters/nanoparticles with precise size control via deprotonation of the ligand”, to be published in “Applied sciences (I.F = 2.679)”. In this paper, author presented the synthesize of different sized Au NPs / Au NCs via sodium borohydride reduction. This paper requires many revisions as noted below.

1. Introduction need some clarification why the author describes the synthesis of tiopronin-capped gold nanoclusters/nanoparticles and for what purpose? For sodium borohydride based Au NPs synthesize and capping effect author must cite the following references; 1. Chem. Commun., 2014, 50, 14194-14196; 2. Sens. Actuators B, 2016, 226, 44-51; 3. Analyst, 2012,137, 5382-5386; 4. Microchem. J, 2021, 160, 105754 and 5. Mater. Res. Express, 2019, 6 1150f2.
2. There is no demonstrated evidence for capping of tiopronin over NPs or NCs surface, where is the FTIR data? Without such data, how the author verifies the functionalization. Author describes the diverse nanoparticle size by tuning the molar ratio, but how they confirm the entire capping of tiopronin? Any centrifugation used to purify? Author also need to provide dispersion concentration of NPs / NCs in 1 mL solution.   
3. The scale bars of TEM images must be improved to readable fashion. Clarity of insets of Figures 2(a)-(h) must be improved for the readers.
4. Majority of information in Results sections looks like discussion, which should be shifted to discussion section. Currently, discussion section is deficient with respect to gathered information from the data.
5. Figures 2-4 are not described with clarity in the result section to justify the manuscript publication.
6. How about the powder XRD pattern of synthesized Au NPs / Au NCs? How about the Zeta potential of the NPs or NCs?
7. At tiopronin to gold ratios of 1:3 and 1:2, the PL intensities of NCs must be supported by the quantum yield data.
8. Where is the conclusion section accounting merits and limitation of the method?
9. There is no application hinted or delivered for “Applied Sciences”?
10. Reference section is not up to date, it should be improved.

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Changes has not been incorporated as per suggestion/comments and cannot be accepted in present from!

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

Author improved the manuscript as per the suggestion. I am satisfied by reply and improvement in many queries. But, before acceptance, following points must be addressed.

1. I agree that while solidifying the NPs they may undergo aggregation, which may not affect the functional unit finding from FTIR. To justify the functional unit capping over Au NPs, supplement the FTIR. With out any FTIR data, this paper may loss the readability. On the other hand, FTIR can be done by coating the samples over Si-wafer also.

2. There are no journal names mentioned throughout the reference section. Please mention the journal names (see Refs 1-31).

Author Response

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Author Response File: Author Response.docx

Round 3

Reviewer 1 Report

All queries has been addressed properly. Hence can be accepted in present form.