Antibacterial UV-Curable Gel with Hydroxyapatite Nanoparticles for Regenerative Medicine in the Field of Orthopedics

Round 1

Reviewer 1 Report (New Reviewer)

Comments and Suggestions for Authors

The manuscript, titled “Antibacterial UV-Curable Gel with Hydroxyapatite Nanoparticles for Regenerative Medicine,” presents the development of a novel composite material based on UV-curable acrylates, natural gelatin, and nanoparticles (hydroxyapatite, silicon oxide, and zinc oxide) for potential applications in orthopedics and dentistry. The study explores material synthesis, characterization, antimicrobial properties, and suitability for metal implant coatings and cartilage repair. The proposed composite exhibits partial resorption, biocompatibility, and antimicrobial activity, making it a promising candidate for regenerative medicine. The study addresses an important topic in the field of biomaterials and regenerative medicine. However, there are several areas that require further clarification, improved experimental rigor, and in-depth discussion to meet the standards of a high-impact journal.

 

1. The particle size distribution of hydroxyapatite nanoparticles is inconsistently reported. The manuscript indicates an increase in particle size after gelatin addition (from 135 nm to 174 nm) but lacks a clear explanation for this phenomenon. The interaction mechanism between the carboxylate shell and hydroxyapatite nanoparticles should be elaborated.

2. The creep and recovery analysis provides insights into the material’s mechanical stability. However, the connection between gelatin incorporation and improved elasticity remains speculative. A deeper discussion of the molecular interactions leading to these effects is needed.

3. The antimicrobial tests are performed on several microorganisms, but the manuscript does not quantify the active antimicrobial agent’s contribution (zinc oxide) relative to other components. A comparative study of materials with and without ZnO nanoparticles would clarify its role.

4. The study suggests potential clinical applications in orthopedics and dentistry but does not evaluate the in vivo performance or degradation kinetics of the material. Incorporating animal studies or simulations would greatly enhance the manuscript’s translational value.

5. The potential for UV-curable gels to remain non-toxic during application requires additional discussion, particularly concerning UV exposure duration and depth of curing.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report (New Reviewer)

Comments and Suggestions for Authors

I have analyzed the manuscript "Antibacterial UV-curable gel with hydroxyapatite nanoparticles for regenerative medicine in the field of orthopedics" and highlight the weak points as follows:

The introduction section should be improved in the sense that other information presented in other bibliographic sources should also be taken into account (within the bibliographic sources only 2 bibliographic sources from the last 5 years are presented). Some references in the text are not filled in (eg reference 12).

The purpose of the research is stated in the abstract and introduction, but the main contribution of the paper (compared to the existing literature) is not clearly differentiated. A stronger claim on innovation is needed.

The "Materials and Methods" section is not detailed enough for replicability. Technical parameters for IR, TMA and other equipment are not specified. Details about the synthesis conditions (time, temperature, exact ratios) are sometimes general.

Most of the figures do not have a proper resolution. Some graphics and images are difficult to interpret. Particle size histograms do not have clear axis labels. SEM images are not discussed in detail.

Mechanical and structural stability tests are short-term. No data on degradation or behavior in environments simulating real conditions are included.

The TMA data are not detailed enough to support conclusions about mechanical stability.

The XRD results could benefit from further analysis regarding the influence of SiO₂ and gelatin nanoparticles on the crystal structure.

A clear highlighting of the novelty brought in the research compared to other similar materials described in the specialized literature is required. Also, the applications are stated generically and not sufficiently supported by the data presented. For example, it is not clear how the material behaves in the long term in real conditions.

Although potential applications in medicine are mentioned, the manuscript only includes antimicrobial tests and physicochemical characterizations.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report (New Reviewer)

Comments and Suggestions for Authors

The authors responded to the comments made and improved the paper accordingly.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

In its current state, the manuscript contains many technical inconsistencies related to the fundamentals of composite preparation, as was determined from the abstract and introduction. The experimental section does not describe the methodology used to produce any constituent of the composite materials. Instead, some information is provided in the results and discussion section. A rheology study is required to verify the particle dispersion homogeneity and the inferences; carboxylate forms a shell on the surface of the HA nanoparticles. The characterisation does not provide evidence of the formation of Si-HAp substituted nanoparticles. Wet chemical analysis is highly recommended to determine the chemical composition of the HAp, together with a microstructural evaluation of the composites to reveal the matrix distribution and the HAp, ZnO and SiO2. FT-IR results do not provide evidence supporting the differences authors claimed between the raw material and the composites prepared, as reference check https://doi.org/10.1016/B978-0-08-102834-6.00012-4. I suggest the authors check the references included for comparison and analyse how far their research work is regarding originality, readership, clearness and objectivity. Discussions are somewhat speculative and do not contribute to the originality of the research. The conclusion is a critical part of the manuscript, and it should provide a correct analysis, including the new findings and the physicochemical properties investigated. The absence of an originality statement to support the new findings from the present research work is a significant gap that needs to be addressed. A robust conclusion is essential to validate the research and its contribution to the field. Therefore, I do not support this manuscript for further publication in J. Compos. Sci. because of the lack of novelty and inconsistencies in the literature survey, experimental methodology, characterisation, results, and discussion.

Comments on the Quality of English Language

The English language level in the manuscript leaves much to be desired; an example is the manuscript title, which gives an ambiguous idea. Precise and accurate language is essential for effective communication in scientific writing.

 

Author Response

In its current state, the manuscript contains many technical inconsistencies related to the fundamentals of composite preparation, as was determined from the abstract and introduction. The experimental section does not describe the methodology used to produce any constituent of the composite materials. Instead, some information is provided in the results and discussion section. A rheology study is required to verify the particle dispersion homogeneity and the inferences; carboxylate forms a shell on the surface of the HA nanoparticles. The characterisation does not provide evidence of the formation of Si-HAp substituted nanoparticles. Wet chemical analysis is highly recommended to determine the chemical composition of the HAp, together with a microstructural evaluation of the composites to reveal the matrix distribution and the HAp, ZnO and SiO2. FT-IR results do not provide evidence supporting the differences authors claimed between the raw material and the composites prepared, as reference check https://doi.org/10.1016/B978-0-08-102834-6.00012-4. I suggest the authors check the references included for comparison and analyse how far their research work is regarding originality, readership, clearness and objectivity. Discussions are somewhat speculative and do not contribute to the originality of the research. The conclusion is a critical part of the manuscript, and it should provide a correct analysis, including the new findings and the physicochemical properties investigated. The absence of an originality statement to support the new findings from the present research work is a significant gap that needs to be addressed. A robust conclusion is essential to validate the research and its contribution to the field. Therefore, I do not support this manuscript for further publication in J. Compos. Sci. because of the lack of novelty and inconsistencies in the literature survey, experimental methodology, characterisation, results, and discussion.

 

Comments on the Quality of English Language

The English language level in the manuscript leaves much to be desired; an example is the manuscript title, which gives an ambiguous idea. Precise and accurate language is essential for effective communication in scientific writing.

Answer

Regarding the reviewer's comments

- The authors believe that the article provides enough information to describe the methodology.

- The authors believe that DLS - standard method for determining the particle size

- The authors believe that ATR (IR spectroscopy) - allows to prove and characterize the formation of new bonds

- The authors proposed a method for obtaining GA particles in accordance with previously developed other scientific (Precursors for obtaining calcium phosphates are calcium salts and phosphoric acid derivatives , conditions for the transformation of calcium phosphates into GA - рH= 9-10) . The introduction of silicon oxide, zinc oxide nanoparticles and carboxylate monomer into the reaction medium cannot significantly change the synthesis conditions. So, it is not required wet chemical analysis.

- In the ATR spectrum (IR spectrum) of nanocomposite (in our case) the strong band at
1550 cm^-1 are observed. The 1560 cm^-1 band can be attributed as the valence vibration band of the carboxylate anion.  At the same time, this band has a weak intensity in the spectra of pure carboxylate. This band is enhanced and has a long-wave shift in the spectrum HA nanoparticles with organic carboxylate shell. This fact confirms the bonding of the carboxylate monomer by its carboxylate group to the surface of HA nanoparticles. Also, the correctness of the formation of an organic shell on the surface of GA is confirmed in https://doi.org/10.1016/B978-0-08-102834-6.00012-4 . It is proved by numerous examples that HA nucleation is initiated through a carboxyl group if it is present in the reaction medium.

- Novelty and originality. The authors developed and studied a new material and proposed a method for obtaining it to solve problems in orthopedics and dentistry. This material can be spread on arbitrary-shaped surfaces and photo-cured. This type of material may be useful in laparoscopy. When in an aquatic environment, some part of the material disappears, as this process occurs due to the resorption of gelatin. At the same time, the other part of the material based on a composite of silicon oxide and polymerized acrylates is retained. The result is a porous material in which the bone or cartilage cells can function normally. Such a composite coating will increase the service life of a metal implant, which is usually embedded in the bone and wears it down. Material serves as a protective layer that reduces friction between organic tissues and a metal implant and can be a solution to the problem of aseptic instability of metal implants. Thus, a feature of the material is that it solves the problem of aseptic loosening when used as a coating for metal implants. Typically, а natural or some types of synthetic polymers are used for biomaterials. Their use requires either solvents or complex equipment methods. The method proposed by the authors is simpler. The problem is that gelatin does not allow one to obtain a homogeneous photocurable biocompatible material. The authors succeeded in solving this problem and obtaining a solid material based on a mixture of acrylates and gelatin using photocuring.

Reviewer 2 Report

Comments and Suggestions for Authors

The paper is well developed proving practical significance, and can be accepted after minor revision, taking into account the following

-Please, improve Figures 3, 4, and 5 in terms of clarity

 

-Please, check the text in Figure 9 

Comments on the Quality of English Language

The English could be improved

Author Response

The paper is well developed proving practical significance, and can be accepted after minor revision, taking into account the following

• Please, improve Figures 3, 4, and 5 in terms of clarity

 Corrected texts and captions for figures 3, 4, 5

Corrected texts and captions for figures 3

Initial version

The phase composition of HA obtained in solution with different components was determined by X-ray diffraction (XRD) analysis. Figure 3 shows the XRD results for HA nanoparticles powder obtained (sample 4); HA powder obtained in solution without additives (sample 1); HA particle powder formed in solution with silicon oxide nanoparti-cles (sample 2); HA nanoparticle powder formed in solution with carboxylate (sample 3).

Corrected

Since the structural formula of the Bis - GMA acrylate monomer has been added to the article, all figures have shifted to 1.

The phase composition of HA obtained in solution with different components was determined by X-ray diffraction (XRD) analysis. Figure 4 shows the XRD results for HA nanoparticles dry powder: HA powder obtained in solution without additives (sample 1 р); HA particle powder formed in solution with silicon oxide nanoparticles (sample 2 р); HA nanoparticle powder formed in solution with carboxylate (sample 3 р). HA particle powder formed in solution with silicon oxide nanoparticles and with carboxylate (sample 4р).

Initial version

Figure 3. XRD results of HA samples obtained according to the above technique in aqueous solution with different accompanying components: (a) HA and HA particles formed in the presence of silicon oxide nanoparticles only; (b) HA and HA nanoparticles formed in solution with carboxylate; (c) HA and HA particles formed in the simultaneous presence of silicon oxide nanoparticles and carboxylate. .

Corrected

Figure 4. XRD results of HA powder samples (table 2) obtained in aqueous solution with different accompanying components: (a) HA (sample 1) and HA particles formed in the presence of silicon oxide nanoparticles only (sample 2); (b) HA (sample 1) and HA nanoparticles formed in solution with carboxylate (sample 3); (c) HA (sample 1) and HA particles formed in the simultaneous presence of silicon oxide nanoparticles and carboxylate (sample 1).

Corrected texts and captions for figures 4.

Initial version

The processes of organic carboxylate shell formation with the surface of HA nanoparticles were investigated by IR spectroscopy. As can be seen (Fig. 4) in the IR spectrum of Si-HA particles modified with 2 carboxylates, the most notable peaks were at 1019 cm-1 (corresponding to PO43- v3 stretching), 962 cm-1 (associated with PO43-, v1 stretching) and 600, 560 cm-1 (related to PO43-, v bending) [22].  The presence of the 1560 cm-1 band can be attributed as the valence vibration band of the carboxylate anion. In the IR spectrum of nanocomposite (in our case) the strong band at 1550 cm-1 are observed. At the same time This band has a weak intensity in the spectra of pure carboxylate. This fact confirms the bonding of the carboxylate monomer by its carboxylate group to the surface of HA nanoparticles.  In [23] it is proved by numerous examples that HA nucleation is initiated through a carboxyl group if it is pre-sent in the reaction medium.

Corrected

The processes of organic carboxylate shell formation with the surface of HA nanoparticles were investigated by ATR (IR spectroscopy). As can be seen (Fig. 5) in the spectrum of Si-HA particles modified with carboxylates, the most notable peaks were at 1019 cm^-1 (corresponding to PO₄^3- v3 stretching), 962 cm^-1 (associated with PO₄^3-, v1 stretching) and 600, 560 cm-1 (related to PO₄^3- ,
v bending) [22].  The presence of the 1560 cm^-1 band can be attributed as the valence vibration band of the carboxylate anion. In the spectrum of pure carboxylate monomer, we observe a weak intensity band at 1550 cm^-1. This band is enhanced and has a long-wave shift in the spectrum HA nanoparticles with organic carboxylate shell. In [23] it is proved by numerous examples that HA nucleation is initiated through a carboxyl group if it is present in the reaction medium. This fact confirms the bonding of the carboxylate monomer by its carboxylate group to the surface of HA nanoparticles.

Initial version

Figure 4. IR spectra: 1 — silica hydroxyapatite nanoparticles (black); 2 — silica hydroxyapatite nanoparticles surface-modified with carboxylate (red); 3 — monomer carboxylate (blue).

Corrected

            Figure 5. IR spectra: 1 — silica hydroxyapatite nanoparticles (black, sample 2 in table 2 or 3); 2 — silica hydroxyapatite nanoparticles surface-modified with carboxylate (red, sample 4 in table 2 or 3); 3 — monomer carboxylate (blue, AL).

Corrected captions for figures 5

Initial version

Figure 5. Changes in relative mass of nanocomposite films: (a) based on BisA/Al monomers; (b) based on BisA/Al monomers with gelatin.

Corrected

Figure 6. Changes in relative mass of film samples (table 1) when soaking in water: (a) nanocomposites 2(Bis1/1+ZnO) and 4 (Bis4/6 +ZnO) based on monomers only; (b) nanocomposites 1 (Bis1/1+Gel+ZnO) and 3 (Bis4/6+Gel+ZnO) based on monomers with gelatin.

• Please, check the text in Figure 9 

Initial version

3.5. Antimicrobial properties

The study for antimicrobial activity was carried out on 5 cultures of microorganisms: Candida albicans, Staphylococcus aureus, E. coli, Klebsiella pneumonia, Acinetobacter baumannii. The films were previously treated with UV rays in a laminar flow cabinet. The duration of the UFO is 40 minutes. The nutrient medium was prepared in advance and poured into Petri dishes. The pieces of film were placed 2 pieces in one cup and placed in a thermostat.

The results of the analysis showed that the films have antimicrobial properties, in-habit the growth of all 5 studied cultures (Figure 9).

Table 5 shows the dynamics of the suppression of the growth of microorganisms, measurements were carried out for 196 hours. The suppression zone decreased slightly over time.

 

Corrected

3.5. Antimicrobial properties

The study for antimicrobial activity was carried out on 5 cultures of microorganisms: Candida albicans, Staphylococcus aureus, E. coli, Klebsiella pneumonia, Acinetobacter baumannii. The nanocomposite films were previously treated with UV rays in a laminar flow cabinet. The duration of the UFO is 40 minutes. The nutrient medium was prepared in advance and poured into Petri dishes. The pieces of film were placed 2 pieces in one cup and placed in a thermostat. The results of the research are presented in Figure 10 and Table 5. Figure 10 shows the results of studies for two cultures (Staphylococcus aureus, E. coli, Klebsiella pneumonia). For other cultures the results are similar. Table 5 shows the dynamics of the suppression of the growth of microorganisms, measurements were carried out for 196 hours. The suppression zone decreased slightly over time. The results of the analysis showed that the films have antimicrobial properties, as they inhibit the growth of cultures.

Comments on the Quality of English Language

The English could be improved

Reviewer 3 Report

Comments and Suggestions for Authors

Burukova et al. constructed a UV-curable antibacterial gel using zinc oxide and silicon-substituted hydroxyapatite nanoparticles for use in regenerative medicine, namely orthopedics. The following issues need to be addressed:

 

1.        The abstract is informative but overly dense. Could key features like "20% pore volume" be summarized more succinctly? And also state significance of partial resorption compared to complete resorption?

2.        In Figure 1 clear representation of HA particle size, but the axes are not labeled descriptively. And why does the addition of gelatin significantly increase particle size and  can this imply any potential limitations in material consistency?

3.     From Table 4 it is unclear why weight loss varies so dramatically between compositions and is weight loss due to soaking affect questioning the long-term structural stability of coatings?

4.   In Figure 9 the labeling should be clear for suppression zones and providing numerical inhibition values would be helpful and clear?

5.   Can authors explain was the effect of UV curing duration (40 minutes) on mechanical properties and degradation analyzed and how does pH 9–10 influence nanoparticle synthesis compared to other pH levels?

6.      Authors mention XRD data confirm phase purity, but no discussion on amorphous content seen for Figure 3?

7.        Creep-recovery tests suggest good elastic properties, but Figure 6 could use a clearer legend. And all the figures legends be clear and all figures should be replaced with high resolution figures.

8.  Have clinical safety concerns, such as cytotoxicity or in vivo performance, been tested or planned for future work by authors?

9. Phrases like "partially resorbable porous polymer coating" are repeated frequently. and some typos need to be corrected.

 

 

Comments on the Quality of English Language

9. Phrases like "partially resorbable porous polymer coating" are repeated frequently. and some typos need to be corrected.

Author Response

Burunkova et al. constructed a UV-curable antibacterial gel using zinc oxide and silicon-substituted hydroxyapatite nanoparticles for use in regenerative medicine, namely orthopedics. The following issues need to be addressed:

1.       The abstract is informative but overly dense. Could key features like "20% pore volume" be summarized more succinctly? And also state significance of partial resorption compared to complete resorption?

 

Answer

The authors decided that this volume of the abstract will allow any reader to understand the problem of this article.

In an aquatic environment, some part of the material disappears, as this process occurs due to the resorption of gelatin. At the same time, the other part of the material based on a composite of silicon oxide and polymerized acrylates is retained. The result is a porous material in which the bone or cartilage cells can function normally. Such a composite coating will increase the service life of a metal implant, which is usually embedded in the bone and wears it down. Material serves as a protective layer that reduces friction between organic tissues and a metal implant and can be a solution to the problem of aseptic instability of metal implants. Thus, a feature of the material is that it solves the problem of aseptic loosening when used as a coating for metal implants.

2. In Figure 1 clear representation of HA particle size, but the axes are not labeled descriptively. And why does the addition of gelatin significantly increase particle size and can this imply any potential limitations in material consistency?

Answer

In Figure 1, the authors labeled the axes descriptively.

Gelatin forms bonds with the surface of the HA particles due to its functional groups and this leads to an increase in their size. As we have established for this composite material, no more than 10-15 wt% of gelatin can be added to obtain a homogeneous medium.

3.    From Table 4 it is unclear why weight loss varies so dramatically between compositions and is weight loss due to soaking affect questioning the long-term structural stability of coatings?

Answer

One of the monomers (Bis) forms a cross-linked insoluble structure, while carboxylate (AL) can only form a linear structure. Also, carboxylate (AL) polymerizes poorly, and therefore after the photoprocess there is a residual amount of soluble monomers. Accordingly, the ratio of concentrations of such monomers affects the cross-linked structure of the final material and weight loss during soaking. It is important that a porous non-resorbable material (polymer with silicon oxide nanoparticles and HA particles) is formed during soaking.   The bone or cartilage cells, etc. can grow and function normally in porous non-resorbable material. Thus, the long-term structure of the material changes constantly, that is, it adapts to the needs of growing tissues.

4.  In Figure 9 the labeling should be clear for suppression zones and providing numerical inhibition values would be helpful and clear?

Answer

We agree with the reviewer. However, we used the traditional way of presenting the results of this method.

 

5.  Can authors explain was the effect of UV curing duration (40 minutes) on mechanical properties and degradation analyzed and how does pH 9–10 influence nanoparticle synthesis compared to other pH levels?

Answer

The authors found that 30 minutes of irradiation is sufficient to form a solid material. The authors did not conduct studies on mechanical properties and degradation as a function of irradiation time. As established in a number of scientific papers, the formation of HA particles from calcium phosphates requires a pH = 9-10 environment. Therefore, the authors used such conditions.

 

6.     Authors mention XRD data confirm phase purity, but no discussion on amorphous content seen for Figure 3?

Answer

The authors consider the discussion of the amorphous phase to be obvious, so there is no separate explanation in the text.

 

7.       Creep-recovery tests suggest good elastic properties, but Figure 6 could use a clearer legend. And all the figures legends be clear and all figures should be replaced with high resolution figures.

Answer

The authors agree with the comment and have made corrections to the figure legends.

 

8. Have clinical safety concerns, such as cytotoxicity or in vivo performance, been tested or planned for future work by authors?

Answer

As shown in our work [20] nanocomposites based on these monomers and silicon oxide nanoparticles are non-toxic and biocompatible, so these monomers were used in the development of nanocomposites for metal implant coatings

 

9. Phrases like "partially resorbable porous polymer coating" are repeated frequently. and some typos need to be corrected.

Answer

 The authors agree with the comment.

Reviewer 4 Report

Comments and Suggestions for Authors

Many important characterizations and discussions are missing in this research and current manuscript, which results in current results cannot support the conclusions claimed by the authors. Detailed comments are as follows:

1. In line 21, which results in this manuscript can support the polymer material reported here can "be partially absorbed"?

2. In line 85, which results in this manuscript are based on the "metal implant coatings" and which results show the "orthopedic" and "dental" application?

3. In line 86, no results show the material can coat "arbitrary-shaped surfaces".

4. In line 88 to 91, no results or evidence shown in this manuscript can support this claim. 

5. In section 3.2, can the authors provide the SEM images of these particles?

6. In line 285, which results can verify that these ""at least 20%" of weight are degraded?

7.In line 317, no results in this manuscript show "a more net-like" structure.

8. In line 339-342, the authors should add evidence or data not just description to make their claim convincing. 

Author Response

1. In line 21, which results in this manuscript can support the polymer material reported here can "be partially absorbed"?

This is a random error.

Correct text

The uniqueness of this polymer material lies in its ability to be partially resorbable, which con-tributes not only to the growth of bone cells, but also serves as a protective layer that reduces friction between organic tissues and a metal implant and can be a solution to the problem of aseptic instability of metal implants.

2. In line 85, which results in this manuscript are based on the "metal implant coatings" and which results show the "orthopedic" and "dental" application?

Answer

The result of the authors' work is the development and study of a new composite material and the method for its production. The material is suitable for coatings of metal implants, which are used in both orthopedics and dentistry.

3. In line 86, no results show the material can coat "arbitrary-shaped surfaces".

Answer

High viscosity and good flowability of the material ensure spreading onto the arbitrary-shaped surfaces.

4. In line 88 to 91, no results or evidence shown in this manuscript can support this claim. 

Answer

The authors agree with the comment and offer a more probabilistic formulation in the text

Correct text

The peculiarity of the material is that the porous polymer partially absorbable coating will most likely be able to ensure not only the proliferation of bone cells, but will also serve as a damping layer against abrasion of organic tissue by the metal of the implant.

5. In section 3.2, can the authors provide the SEM images of these particles?

 

Answer

Since the particles are synthesized in solution, their agglomeration is observed when the solvent dries. For this reason, the particle size was determined by the DLS method. The SEM method can determine the composition of the particles; however, the authors do not consider it informative to present an SEM image of the particles.

6. In line 285, which results can verify that these ""at least 20%" of weight are degraded?

       Answer

The change in the composite weight in an aqueous medium is due to the dissolution of gelatin and unpolymerized carboxylate monomer. Water analysis showed that there is carboxylate and gelatin in the water. The percentage of weight change depends on the composition of the material. This can be considered as degradation of the composite.

7.In line 317, no results in this manuscript show "a more net-like" structure.

Answer

The authors added the structural formula of Bismonomer and text to paragraph 2. Materials and Methods.

Nanocomposites are formed on the basis of the Bis and carboxylate monomer. The monomer Bis has two acrylate groups, i.e. it has two double bonds. During photopolymerization, a cross-linked structure is formed in volume. The carboxylate monomer has one C=C bond, so a linear structure is formed during photopolymerization. Different ratios of the monomer concentrations affect the percentage of crosslinking of the structure.

8. In line 339-342, the authors should add evidence or data not just description to make their claim convincing.

 The authors decided that the article has a large amount of data, especially since the photo of the plates with the applied composite is of low informatization. We can add a photo.

            

                                      Before                                                     After

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors conducted achievements to explain some of the comments addressed by my side in the first review. I do not agree with the reasons given to rebut previous comments. This version still with lots of fundamental deficiencies, which were addressed in my previous review. Therefore, I have pointed out that this manuscript has not the potential for publishing in the JCS, after evaluate the document I concluded still no potential for be published at JCS.

Reviewer 4 Report

Comments and Suggestions for Authors

The quality of manuscript after revision has been improved.