Characterization of Bioactive Glass Synthesized by Sol-Gel Process in Hot Water
, Thi Hoa Bui 2,3, Elena V. Guseva 4, Anh Tuan Ta 4, Anh Tien Nguyen 5, Thi Trong Hoa Hoang 6 and Xuan Vuong Bui 7,8,*Round 1
Reviewer 1 Report
Paper deals with an always interesting topic, i.e, bioactive glasses. Paper sounds well and is worthy for
publication when authors consider some minor remarks.
1) Concerning the material, I think that there is abasic paper that should be mentioned in the references;
Bioactive glass nanoparticles obtained through sol–gel chemistry byAnna Lukowiak, Jonathan Lao,
Josephine Lacroixd and Jean‐Marie Nedelec, Communications, 49(59), 6620‐6622 – 2013;
https://doi.org/10.1039/c3cc00003f
2) Please give some information regarding the employed sintering process. A reference would be welcome
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Reviewer 2 Report
The reviewed paper describes slightly modified sol-gel synthesis procedure of binary glass which shows bioactivity. There are available numerous papers focused on similar research so, the novelty is limited. The topic is not in the main interest of the Journal as the study concern mainly glass structure (including information about growth of hydroxyapatite). Nevertheless, the report is scientifically correct and worth of attention is the proposed catalyst-free synthesis as well as good bioactivity of the derived glass. Thus, I could recommend to accept the paper but after correction as indicated below.
- Authors proposed multistep drying and calcination procedure (70, 100, 150, 200, 600, 700 C) – is there any specific reason for that? What if the sample was dried at 75 C and then directly calcined at 700 C? Would there be any difference?
- Figure 4 shows that samples were calcined at 700, 800, 900, and 1000 C, please add this information in Experimental section.
- “The in vitro experiment was performed by soaking the glass samples in the simulated body fluid 80 (SBF) at several times.” This sentence is not clear – what “several times” means?
- Glass composition: “The synthetic glass showed a moderate difference in composition compared to the theoretical composition (Table 1). This difference is due the amorphous structure of synthetic glass, resulting in an uneven distribution of elements in the glassy network.” This statement is not convincing. First of all, the measurement errors should be given in Table 1. The ions distribution might be not homogenous in the sample, but with the multi-point analysis, the average composition should be close to the theoretical one.
- How about changes of glass composition after immersion in SBF? In my opinion, the EDX analysis of those samples should be added in the article.
- Aggregation: “These particles seem to be aggregated to form the mesoporous structure of synthetic glass. This is explained by the self-assembly phenomenon. The immobilization of Ca2+ ions on the surface of silica particles results in the change of chemical surface, leading to the agglomeration of particles [18-19].”
The self-assembly phenomenon is another process than aggregation observed here (see for example: Xu et al. (2010) doi.org/10.1007/s11706-010-0020-5 or Kohoutek et al. (2020) doi.org/10.1016/j.colsurfa.2020.124625).
The last sentence is not clear. Are Ca2+ ions present only on the surface of silica particles? Why would they lead to agglomeration?
- The important point to be corrected before publication is also the reference list. Please check the reference numbers because I don’t find information from analysis of N2 adsorption/desorption isotherms in ref [16] (l. 148) or 10 (Table 2). Verify correctness of those and others references. Moreover, add proper ref. number in the last row of Table 2.
- If possible, please add JCPDS pattern of HA in figure 4.
- 178: “After 48 hours, a mitigation of cellular viabilities was determined” – what exactly Authors have in mind?
- Grammar must be corrected because basic mistakes are present in the text (e.g. line30: “when immersed in an physiological solution”; l. 8: “experiments were performed in according with”, l. 180: “the material is toxicity“, and others)
- Other mistakes:
- l. 35 “meting” should be “melting”
- l. 55 “75SiO2-16CaO-5Na2O-P2O5” should probably be „75SiO2-16CaO-5Na2O-4P2O5”
- l. 78 „Sbf” should be „SBF”
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Reviewer 3 Report
The paper : “Synthesis and Characterization of Bioactive Glass by Sol-Gel Process in Hot Water” is addresses an interesting topic and describes clearly the experimental methods and results. Therefore, it may be recommended for publication after minor revision:
Line 24: it was not specified what “SBF” means
Line 35: the “Melting” word was misspelled.
Line 41: change “were” into “was”.
Line 42: change “requires” into “require”.
Line 49: remove the hyphen between "meso" and "porous"
Line 50: change “were” into “are”.
Line 52: add “the” between “for” and synthesis”.
Line 54: change “used” into “use”
Line 58: the sentence “without using acid catalyst” is redundant. It has already written in line 56.
Line 59: change “is” into “was” because this phrase refers to the sentence “Recently, a bioactive glass […] was successfully synthesized…”
Line 60: add “a” before “bioactive glass”.
Line 62: The sentence is not clear. Maybe you meant to write that it still shows bioactivity properties
Line 67: the “Experimental” word was misspelled.
Line 70: change the dot with a mid dot.
Line 70: change “was” into “were”
Line 72: change “ was” into “ were”
Line 73: change “form” into “formed”
Line 78: Write SBF with capital letters.
Line 86: delete “in” before “according”.
Line 100: I suggest you choose between Celsius or Kelvin units to exprime the temperature.
Line 110: write “Field Emission” with capital letters.
Line 111: rewrite FESEM as “FE-SEM” because in all article it is written in this way.
Line 117: change “are” into “is”.
Line 123: shift the title to next page.
Line 124: I suggest you add a reference to confirm that these XRD analysis. See Tranquillo, E.; Barrino, F.; Dal Poggetto, G.; Blanco, I. Sol–Gel Synthesis of Silica-Based Materials with Different Percentages of PEG or PCL and High Chlorogenic Acid Content. Materials 2019, 12, 155.
Line 132: add to after “due”
Lines 146-148: references used to compare “N2 adsorption/desorption data”in table 2 seem to be wrong. I suggest you adjust them.
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Round 2
Reviewer 2 Report
Comments in the attachment
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