Review Reports

Round 1

Reviewer 1 Report

Introduction can be shortened and instrumental passages can be ommitted.

please, explain line 180 - why the azelaic acid ratio was included. paste the reference for this approach.

line 307 check the flow rate of the mobile phase.

table 8 - improve the quality

generally, the authors present well done study

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

A very relevant and important case study with great potential impact. The analytical set-up is robust and the study is accurate, but I have some observations to strengthen the manuscript:

 

My main observation is that the relevance of this study is driven by the importance of the sites and the use of state-of-the-art diagnostics.  Both these aspects should be strengthened to improve the paper:

 

Intro: a quick intro to the statues’ location, composition and structure is necessary at the very start of the introduction, for less familiar readers. Also, a deeper description of the degradation state of the sites is important.

 

Intro µFTIR lines 96-100: because the article serves as a state-of-the-art application of diagnostics to artworks, I think this paragraph should mention, with relevant references, the other possibility current available for µFTIR, i.e. Focal Plane Array detectors which have SR spatial resolution and have been used recently to study paintings and historical/artistic textiles, see:

https://doi.org/10.1038/s41598-019-53763-5

https://doi.org/10.1021/acs.analchem.6b04065

 

Discussion/conclusions: such a vast characterization should link more tightly with indications on the actual degradation state of the artifacts and possibly suggestions for their conservation, else the risk is to have an extensive list of compositional info that per se would fit better in a specialized diagnostic/analytical journal. I find this to be an issue of several diagnostic papers in conservation science. The authors should deepen this aspect within the scopes of the article.

Author Response

Please see the attachment.

Author Response File: Author Response.docx