A Novel Electrochemical Sensing Platform for the Sensitive Detection and Degradation Monitoring of Methylene Blue

Round 1

Reviewer 1 Report

A good manuscript describing a useful method and material. It contains, however, several technical and formal flaws so a major revision is mandatory. If these are eliminated, the manuscript will be much more attractive. In more detail:

* Title: Should be reduced in length and more attractive to the readers

INTRODUCTION

The Introduction part contains trivial statements. Note that readers are experts who know this. They will be bored when reading this. The introduction should be reduced in length and have a focus on current analytical challenges.

Comments:

1. Figure 2, the NH2-fMWCNT's/GCE shows an extra peak at 0.03 V, more explanation should be added. In addition, all modified electrodes should be tested in blank 0.1M PBS.
2. The electrochemical oxidation mechanism of MB at NH2-fMWCNT's/GCE should be provided.
3. The abbreviations should be defined when they are first used such as GCE.
4. BET data should be added for MWCNT, and NH2-fMWCNT's.
5. Give error bars in figures.
6. In my opinion, the writing of the text should be revised in depth for the sake of clarity and to correct some spelling mistakes.
7. More Recent article should be cited in terms of the advantages of the electrochemical method and photocatalyst

Maheshwaran, S., et al., Microchimica Acta (2021) 188 (9), 1; Kogularasu, S., et al., Microchemical Journal (2021) 168, 106465; Akilarasan, M., et al., Microchimica Acta (2021) 188 (3), 1; Renganathan, V., et al., Ecotoxicology and Environmental Safety (2019) 176, 250

8. A Conclusion should be reduced in length. Focus on conclusions, on the scope (such as applicability to related detection schemes), and also on limitations, but do not repeat figures of merit

Author Response

Please see the attached response

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript entitled “A novel electrochemical sensing platform for the sensitive detection and degradation monitoring of methylene blue which is a toxic dye used in textile industry, food items and medical practices” by Muhammad Mazhar Hayat, Afzal Shah, Jan Nisar, Iltaf Shah, Abdul Haleem and Muhammad Naeem Ashiq, describes the preparation and validation of electrochemical sensor of methylene blue. I like the idea very much, to use NH2 functionalised Carbon nanotubes as sensor for dye pollutant (methylene blue.). However, I have some questions to the authors.

1. The title of the manuscript in my opinion is too long and too describing.
2. Methylene blue has very intensive blue colour (at least in water solution) thus what the authors want to say by “It has a characteristic dark green color with bronze luster.”
3. The authors do not explain the real need for this type of sensor as the dye (MB) has a strong colour even in low concentrations. The photodegradation of MB using TiO₂ catalyst was monitored by electro-sensor and for comparison reason by UV-VIS both techniques give very similar results what is very good but under this conditions the colour of MB in solution is visible by human eye. My question is: what is the detection limit of the sensor?
4. Finally, can the authors give more details (if it is possible) how the NH2 groups were incorporated on CNT? The authors mentioned that the material is the commercially available but sometimes it is possible to get this information.

Summarising, support the manuscript for the publication after minor revistion.

 

Author Response

Please see the attached response

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The presented manuscript has been finely improved according to the reviewer's comments. Therefore, the paper can be accepted as it is. 

Author Response

Dear Referee,

Please find our response in attachment

 

Kind Regards