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Fluorescence microscope observation of the structure of a calcium alginate hydrogel

  • Minoru Aoyagi EMAIL logo
Published/Copyright: March 7, 2022
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Journal of Polymer Engineering
From the journal Journal of Polymer Engineering Volume 42 Issue 5

Abstract

Calcium alginate hydrogels are used in a wide range of applications in the food, medical, pharmaceutical, and cosmetic industries. I have studied a calcium alginate hydrogel as an ultrasound phantom material. This hydrogel is formed using sodium alginate, calcium sulfate dihydrate, trisodium phosphate 12-hydrate, glycerol, and water, and mimics the ultrasound properties of human soft tissue. In this study, the structure of the calcium alginate hydrogel was observed with a fluorescence microscope after staining with the calcium indicator calcein. Two types of hydrogel structures, tape-like and thread-like, were observed by this method. The thread-like structures were rare in the hydrogel, which made them more difficult to find than the tape-like structures. These structures were several micrometers in diameter and longer than the tape-like structures, which were several micrometers to several tens of micrometers wide. The thread-like structures spread out in three dimensions, and existed singly or in aggregates. The outer shape of the aggregated thread-like structures resembled the shape of the tape-like structures, which suggested that the tape-like structures were made up of thread-like structures. The tape-like and thread-like structures are thought to contribute to retention of water, which is the main component of a hydrogel, by surrounding it.

Keywords: calcein; calcium alginate; fluorescence microscope; hydrogel network
Corresponding author: Minoru Aoyagi, Department of Electrical and Electronics Engineering, Nippon Institute of Technology, 4-1 Gakuendai, Miyashiro, Saitama 345-8501, Japan, E-mail:

Funding source: Ministry of Education, Culture, Sports, Science and Technology

Award Identifier / Grant number: 15K01338

Funding source: Japan Society for the Promotion of Science

Funding source: KAKENHI

Award Identifier / Grant number: 15K01338

Acknowledgments

We thank Gabrielle David, PhD, from Edanz (https://jp.edanz.com/ac) for editing a draft of this manuscript.

  1. Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

  2. Research funding: This work was supported by the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT) and the Japan Society for the Promotion of Science (JSPS) KAKENHI (grant number 15K01338).

  3. Conflict of interest statement: The author declares no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

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Received: 2021-09-25
Accepted: 2022-01-22
Published Online: 2022-03-07
Published in Print: 2022-05-25

© 2022 Walter de Gruyter GmbH, Berlin/Boston

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https://doi.org/10.1515/polyeng-2021-0284
Keywords for this article
calcein; calcium alginate; fluorescence microscope; hydrogel network

Articles in the same Issue

  1. Frontmatter
  2. Material Properties
  3. The influence of structural and chemical parameters on mechanical properties of natural fibers: a statistical exploratory analysis
  4. Dual effect of maleic anhydride and gamma radiation on properties of EPDM/microcrystalline newsprint fiber composites
  5. Mechanical and wear behaviour of PEEK, PTFE and PU: review and experimental study
  6. Electrical conductivity and thermal stability of surface-modified multiwalled carbon nanotubes/polysulfone/poly(p-phenylenediamine) composites
  7. Preparation and Assembly
  8. Boehmite-graphene oxide hybrid filled epoxy composite: synthesis, characterization, and properties
  9. Fluorescence microscope observation of the structure of a calcium alginate hydrogel
  10. Fabrication of mixed nanoceramic waste with polymeric matrix membranes for water desalting
  11. Engineering and Processing
  12. Asphalt concrete based on a polymer–bitumen binder nanomodified with carbon nanotubes for road and airfield construction
  13. Variation in final sheet thickness in case of Sutterby fluid during the calendering process
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