Microwave-Assisted Wet Granulation for Engineering Rice Starch–Mannitol Co-Processed Excipients for Direct Compression of Orally Disintegrating Tablets

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript developed a new type of excipient (MW-RM) by using microwave-assisted wet granulation technology, which is a combination of rice starch (RS) and mannitol, for direct compression of oral disintegrating tablets (ODT). The effects of microwave power and time on the particle morphology, crystal structure, pore characteristics, powder flowability, compression performance, and disintegration behavior were systematically investigated. The results showed that the internal steam pressure generated by microwave treatment promoted the formation of porous structures and partially reduced the crystallinity, thereby improving the compressibility, wettability, and flow properties of the excipient. The optimized formula MW-RM-H-30 exhibited rapid wetting (25 s), high water absorption (90.5%), and short disintegration time (31 s). The tablet performance using chlorpheniramine maleate and piroxicam as model drugs was comparable to that of the commercial excipient Starlac®, meeting the requirements of the pharmacopoeia. This study provides an effective strategy for green and scalable excipient engineering.

However, there are still some questions here.

1. The unevenness of microwave treatment and the resulting complexity of process scaling should be fully elaborated in the discussion section to assess the potential challenges and feasibility of the industrial application of this technology.
2. Due to its high porosity and large specific surface area, ODT is usually more sensitive to environmental humidity and temperature. Its stability is an important factor affecting its product quality. It is recommended to conduct at least preliminary stability-related research.
3. It is suggested that the characteristic absorption peaks of the main functional groups should be clearly marked in the infrared spectrum to enhance the readability of the spectrum.
4. The clarity of the SEM images needs to be improved.
5. Page numbers or DOI is missing in many references.

Author Response

We sincerely thank the reviewer for the time and effort devoted to reviewing our manuscript and for the insightful and constructive comments, which have significantly contributed to improving the scientific quality and clarity of the manuscript. Please see the attached file for the detailed, point-by-point response.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The authors provide a very interesting experimental study on microwave-assisted co-processing of rice starch and mannitol. The microwave-assisted granulation is a well-established method; however, the co-processing used by the technique is challenging. The study gives an interesting insight tot he development and formulation work.

I believe that my critical comments, suggestions, and questions below will help make the manuscript more complete and further improve its quality.

Comments for author File: Comments.pdf

Author Response

We sincerely thank the reviewer for the time and effort devoted to reviewing our manuscript and for the insightful and constructive comments, which have significantly contributed to improving the scientific quality and clarity of the manuscript. Please see the attached file for the detailed, point-by-point response.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors,

Thank you for the thorough corrections. There's a minor change I may suggest: on Fig. 6, second row, between the two samples, there's an extra part which should be removed. In the provided images, it's clear that it derives from the top-right corner of the left image.

Year in Ref 43 and 44. must be bold.