Engineering Gold Nanostructures for Cancer Treatment: Spherical Nanoparticles, Nanorods, and Atomically Precise Nanoclusters
Round 1
Reviewer 1 Report
The manuscript "Engineering gold nanostructures for cancer treatment: nanoparticles, nanorods, and atomically precise nanoclusters" by Tang and coworkers aims at summarising recent advances in the use of gold nanoparticles, nanorods and nanoclusters for cancer applications.
After careful consideration, I do not recommend this manuscript for publication. I believe there are some major flaws.
- The authors do not define the different terms used such as nanoparticles or nanorod. By looking at the IUPAC definition for nanoparticles, found here see https://www.degruyter.com/document/doi/10.1351/PAC-REC-10-12-04/pdf, it seems reasonable to say that nanorods are part of the nanoparticle family. Therefore the differentiation made in the manuscript does not make sense.
- Some sentences regarding the shape of the nanoparticles are very confusing. See for example page 4/12 2nd paragraph: “Au nanoparticles can also self-assemble into spherical nanostructure”. According to the first pages of the review, Au NPs are already spherical. Therefore it is not clear what this new spherical nanostructure is.
- It is not clear why it is interesting to use one type of nanostructures compared to another one. For example, all the three types mentionned in the manuscript are described as having almost exactly the same properties.
- Overall, it is impossible to have an idea of the chemical structure of any of the nanostructures mentionned in the manuscript. Details are lacking, such as the shape, dimensions, ligands used for the stabilisation...
Author Response
The manuscript "Engineering gold nanostructures for cancer treatment: nanoparticles, nanorods, and atomically precise nanoclusters" by Tang and coworkers aims at summarising recent advances in the use of gold nanoparticles, nanorods and nanoclusters for cancer applications.
After careful consideration, I do not recommend this manuscript for publication. I believe there are some major flaws.
- The authors do not define the different terms used such as nanoparticles or nanorod. By looking at the IUPAC definition for nanoparticles, found here see https://www.degruyter.com/document/doi/10.1351/PAC-REC-10-12-04/pdf, it seems reasonable to say that nanorods are part of the nanoparticle family. Therefore, the differentiation made in the manuscript does not make sense.
Response: Thanks a lot for the constructive comment. We checked the IUPAC definition very carefully. Yes, nanorods are part of the nanoparticle family. To differentiate the three types of gold nanostructures, in the revised manuscript, “nanoparticles” have been replaced by “Spherical nanoparticles”, and this review only focuses on spherical gold nanoparticles (other shapes of gold nanoparticles are not included) and gold nanorods for cancer treatment.
- Some sentences regarding the shape of the nanoparticles are very confusing. See for example page 4/12 2nd paragraph: “Au nanoparticles can also self-assemble into spherical nanostructure”. According to the first pages of the review, Au NPs are already spherical. Therefore it is not clear what this new spherical nanostructure is.
Response: Thanks a lot for the constructive comment. In the revised manuscript, we have limited the topic on spherical gold nanoparticles. For this sentence of “Au nanoparticles can also self-assemble into spherical nanostructure”, it has been changed into “spherical gold nanoparticles can also self-assemble into three-dimensional nanostructure”.
- It is not clear why it is interesting to use one type of nanostructures compared to another one. For example, all the three types mentioned in the manuscript are described as having almost exactly the same properties.
Response: Thanks a lot for the constructive comment. The three types have different properties, especially have some common yet slightly different ways to make contribution to cancer treatment. In the revised manuscript, we have clearly elaborated that.
Overall, it is impossible to have an idea of the chemical structure of any of the nanostructures mentioned in the manuscript. Details are lacking, such as the shape, dimensions, ligands used for the stabilisation.
Response: Thanks a lot for the constructive comments. Yes, it would be nice to have the chemical structure of the nanostructures mentioned in the manuscript. So, in the revised manuscript, for each example, we did our best to mention the details regarding the shape, dimensions, and ligands used for the stabilization.
Reviewer 2 Report
The authors present a small review about the use of gold nanostructures for nanomedicine. I would rather consider the manuscript a small perspective with selected examples, since it is not at all close to a comprehensive review considering the thousands of studies existing in this field. With respect to this the number of cited and discussed items is quite small and actually many of the existing excellent reviews are not mentioned/cited.
In the discussion of gold nanoparticles it is stated that they absorb light in the NIR range and convert it to heat. This is wrong for spherical gold nanoparticles, only nanorods, nanoshells and some other shapes absorb in the NIR. This should definitely be corrected.
Author Response
The authors present a small review about the use of gold nanostructures for nanomedicine. I would rather consider the manuscript a small perspective with selected examples, since it is not at all close to a comprehensive review considering the thousands of studies existing in this field. With respect to this the number of cited and discussed items is quite small and actually many of the existing excellent reviews are not mentioned/cited.
Response: Thanks a lot for the constructive comment. We have expanded our literature search. Much more papers have been cited (Previous is 43, and now is 95), and many existing excellent reviews are mentioned and cited. We have also mentioned more studies in the revised manuscript, and significant changes have been made in the revised manuscript.
In the discussion of gold nanoparticles it is stated that they absorb light in the NIR range and convert it to heat. This is wrong for spherical gold nanoparticles, only nanorods, nanoshells and some other shapes absorb in the NIR. This should definitely be corrected.
Response: Thanks a lot for the constructive comment. Yes, only nanorods, nanoshells, and some other shapes can absorb in the NIR region. We have revised the description in the spherical gold nanoparticles part.
Reviewer 3 Report
Comment to the Authors
In this review, authors introduced and summarized the researches on cancer therapy using gold nanoparticles, gold nanorods, and gold nanoclusters. Honestly say, this manuscript looks just a serial introduction or selection of researches without any clear focus. In the introduction, authors described "The performance factors including size, morphology, optical property, surface modification, biocompatibility, as well as the permeability and retention effect will be particularly mentioned". These are very important points. I believe that's why authors showed scheme 1, although I'm not sure this illustration is a "scheme". Authors should describe their size and shape, as well as surface properties in more detail for each research and discuss their effects on cancer therapy by comparison. Thus, this review need totally to be revised.
Comments
- Authors selected three type of nanostructures as nanoparticles, nanorods, and nanoclusters. But, what's the difference between them? I can understand, but these are unclear for readers. Nanorods should be included in nanoparticles. At the 2nd line in page 2, authors described "spherical gold nanoparticles and gold nanorods". As shown here, gold nanoparticles includes spherical and rod shaped nanoparticles. This should be totally related to the unclear focus on this review.
- In the scheme 1, authors showed 6 key factors of "Size", "Morphology", "Biocompatibility", "Surface modification", "Optical property", and "Permeability and retention effect". These are important factors. Thus, authors discussed more from the view point of these factors. By the way, these are characteristics of the particles. Thus, "surface modification" is strange. Also, "permeability and retention effect" is unclear and does not fit here.
Author Response
In this review, authors introduced and summarized the researches on cancer therapy using gold nanoparticles, gold nanorods, and gold nanoclusters. Honestly say, this manuscript looks just a serial introduction or selection of researches without any clear focus. In the introduction, authors described "The performance factors including size, morphology, optical property, surface modification, biocompatibility, as well as the permeability and retention effect will be particularly mentioned". These are very important points. I believe that's why authors showed scheme 1, although I'm not sure this illustration is a "scheme". Authors should describe their size and shape, as well as surface properties in more detail for each research and discuss their effects on cancer therapy by comparison. Thus, this review needs totally to be revised.
Response: Thanks a lot for the constructive comment. Compared with figure or table, we tend to believe it is more like a “scheme”. The manuscript has been extensively revised, and we focus on the different ways to make contribution to cancer treatment by the three different types of gold nanostructures including spherical gold nanoparticles, gold nanorods, and gold nanoclusters. In the revised manuscript, the effect of size, shape, and surface properties toward cancer treatment have been compared along with the detailed explanation of some typical example to establish the structure-performance relationship.
Comments
- Authors selected three type of nanostructures as nanoparticles, nanorods, and nanoclusters. But, what's the difference between them? I can understand, but these are unclear for readers. Nanorods should be included in nanoparticles. At the 2nd line in page 2, authors described "spherical gold nanoparticles and gold nanorods". As shown here, gold nanoparticles include spherical and rod shaped nanoparticles. This should be totally related to the unclear focus on this review.
Response: Thanks a lot for the constructive comment. Yes, nanorods are included in nanoparticles. To differentiate them, this review focuses on “spherical gold nanoparticles” and “gold nanorods” while other shapes are not included, and we have made corresponding changes in the revised manuscript.
- In the scheme 1, authors showed 6 key factors of "Size", "Morphology", "Biocompatibility", "Surface modification", "Optical property", and "Permeability and retention effect". These are important factors. Thus, authors discussed more from the view point of these factors. By the way, these are characteristics of the particles. Thus, "surface modification" is strange. Also, "permeability and retention effect" is unclear and does not fit here.
Response: Thanks a lot for the constructive comment. We totally agree with this reviewer. “Surface modification” has been changed into “surface ligand”, and “permeability and retention effect” has been replaced by “stability”, as stability is indeed an important factor as well.
Round 2
Reviewer 1 Report
The manuscript was revised by taking into account most of all reviewers' comments. I still think it lacks a focus in order to review such a topic with so many published articles but I believe it can be accepted for publication.
Author Response
Thanks for the comment. One thing we want to emphasize is that, we do focus on different shaped gold nanostructures for cancer treatments, especially their different ways to make contributions to cure cancer.
Author Response File: 
Author Response.pdf
Reviewer 3 Report
Authors revised their manuscript according to the reviewers' comments. It became a little better. However, I couldn't understand this review well, because the most important issue, that is unclear focus on this review, remains unsolved. In other words, this review looks just a serial introduction or selection of researches without any focus. Authors should describe more details for each research based on a clear focus and discuss their effects on cancer therapy by comparison. Thus, I think this review "totally" needs to be revised.
Author Response
Thanks for the constructive comment. This review focuses on different shaped gold nanostructures for cancer treatments, especially their different ways to make contributions to cure cancer. In addition, per this reviewer’s suggestion, we revised the manuscript carefully, and all the changes are marked in red in the newly revised version.
Author Response File: Author Response.pdf
