Scalability of API-Loaded Multifilament Yarn Production by Hot-Melt Extrusion and Evaluation of Fiber-Based Dosage Forms
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe manuscript describes a newly suggested methodology for the large-scale production of drug-loaded fibers via the melt extrusion technique. The system called “EsoCap” was designed to develop water-soluble filaments based on Polyvinyl alcohol. The steps to produce active ingredients containing fibers were described with the necessary explanations. Together with photos of the prepared setup, it becomes clearer how the fibers are being produced. The following issues need to be addressed for the proper representation of the study:
-What API means or its therapeutic effect is not clear in the manuscript.
-How the hot-melt extrusion process affects the stability of API itself as an active ingredient was not studied.
-The smoothness of the obtained fibers or the homogeneity in their size needs more morphological inspections, like microscopic ones.
-This system was optimized or adjusted for PAA. Is there any comment or suggestion that this system would be applicable for other polymers, or for what type of polymers?
Comments on the Quality of English Language
Minor editing of English language required
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe authors discuss the limited use of fiber-based technologies from the textile industry in pharmaceuticals, highlighting melt extrusion as a common method for medical devices but rare for drug delivery systems. They mention the EsoCap system as an exception that uses melt-extruded, water-soluble filaments for dosage release. The study aims to develop new processes for creating pharmaceutical fibers suitable for targeted drug delivery despite challenges like spinning oil usage.
Please find some of my comments below:
1) Include detailed diagrams and descriptions of the extrusion and spinning setup, along with a step-by-step account of the process parameters used in each stage of the experimentation​​.
2) The article mentions potential challenges with fiber production but lacks in-process control measures to address these issues.
3) Conduct and present a detailed comparative study on the mechanical properties, drug release profiles, and scalability of fibers produced by melt extrusion versus electrospinning​​.
4) Provide a comprehensive section discussing the safety measures and regulatory compliance steps taken to ensure the produced fibers are safe for pharmaceutical use. Include any tests or validations performed to confirm the absence of harmful residues from spinning oils​​.
5) Use advanced techniques such as scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) to characterize the morphological and thermal properties of the fibers. Discuss how these properties influence drug release and fiber performance​​.
6) Investigate and discuss additional applications such as tissue engineering, wound healing, and smart textiles. Provide preliminary results or literature references supporting the feasibility of using these fibers in diverse biomedical fields​​.
7) Add a graphical abstract.
Comments on the Quality of English LanguageMinor editing of English language required.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsDear authors,
I read your paper entitled "Scalability of API-loaded multifilament yarn production by hot melt extrusion and evaluation of fiber-based dosage forms" sent to Pharmaceutics, and here are my comments:
1. The abstract should clearly outline the objectives, methods, key findings, and significance of the study. Currently, it lacks a concise summary of the main results. It should be rewritten in a more concise manner.
2. Which are the novelty and added value of the paper with respect to existent literature?
3. I would recommend extending the Introduction section with more relevant data from the literature and additional references.
4. You should clearly state the objectives of the study at the end of the Introduction section.
5. I suggest breaking down the methods into more subsections for each major step (Hot-Melt-Extrusion, Spinning Process, Knitting Processing).
6. What are the molecular weight and degree of hydrolysis for PVA?
7. In the Results and discussion section, you may include more comparative analysis with previous studies to highlight the significance of your research.
8. You should detail the efficiency of the hot melt extrusion process in producing API-loaded multifilament yarns.
9. You can compare the performance of the produced fibers with existing drug delivery systems, showing the improvements or advantages demonstrated in the study.
10. The authors should discuss the impact of knotting on the mechanical properties, emphasizing that the tight radius of the knot caused increased stress and material fatigue, which resulted in a slight reduction in tensile strength and greater variability. Which are the values of the Young modulus?
Comments on the Quality of English LanguageSuggestions: You should perform a thorough grammar and spell-check to correct minor errors and ensure proper sentence structure. Some technical descriptions can be simplified to enhance readability for a broader audience.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe highlighted points for the study presented in this manuscript seem to be evaluated in detail, and the necessary explanations were included. Especially the steps for the experimental part were expressed better. Based on these corrections, the manuscript becomes more understandable.
Reviewer 2 Report
Comments and Suggestions for AuthorsThe authors managed to address my comments.
Reviewer 3 Report
Comments and Suggestions for AuthorsDear authors,
The paper has been improved and I am ready to give a final positive feedback.
