PONE-D-25-13367Raman spectroscopy identified fingernail compositional differences between sexes and age-related changes but not handedness or fingers in a healthy cohortPLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Partly

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

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Reviewer #1: Yes

Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

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Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: A major issue is whether the clipped nail truley reflects the status of the proximal attached nail. The end of nail is free to environment on both surfaces and possibly altered. In the situation where changes most marked a sample of nail (how many?) attached should be tested and compared to clipped nail.

Reviewer #2: The paper PONE-D-25-13367 explores the application of Raman spectroscopy on fingernails, aiming to detect compositional differences related to sex, age, handedness, and finger origin. The study is interesting and generally well conducted, however there are some issues to solve before publication, in particular to better clarify the novelty in relation to previous studies, actually the authors claim in the conclusions that “our study demonstrated that nails are a suitable tissue for Raman spectroscopy assessment”, suggesting novelty. However, they also state earlier that “our collected Raman spectra of fingernails are in accordance with previous reports”. Please, indicate better the novelty with respect the previous studies.

2) In figure Figure 1a the Raman spectrum of fingerprints is reported, however there are no assignment to the different Raman peaks. This point is fundamental to better understand the variation reported.

3) . Figures 2 and 3 indicate age-related differences, especially in females. However, the discussion lacks depth in explaining the biological basis for these trends. The observation that females in their 40s show the largest differences is intriguing and possibly related to perimenopausal hormonal shifts. This deserves a more structured interpretation supported by citations. However the number of samples is relatively low (5) to enter into the assignment and could generate some confusion to the reader and to the technique. Please explore this part and improve the discussion of the section.

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Reviewer #1: No

Reviewer #2: No

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Raman spectroscopy identified fingernail compositional differences between sexes and age-related changes but not handedness or fingers in a healthy cohort

PONE-D-25-13367R1

Dear Dr. Yin,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

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Kind regards,

Aaron Specht

Academic Editor

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Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #2: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer: Although the work is clearly a preliminary study on the application of Raman spectroscopy to human fingers, it could provide an interesting foundation for future in-depth research. The authors have addressed my previous comments, and I consider the paper suitable for publication in its current form. However, please carefully check the quality of the figures, as the uploaded PDF files are of poor quality.

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If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer: No

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