Effect of drying methods on Acetobacter xylinum bacterial cellulose aerogels and cryogels

Posted on
effect-of-drying-methods-on-acetobacter-xylinum-bacterial-cellulose-aerogels-and-cryogels
Effect of drying methods on Acetobacter xylinum bacterial cellulose aerogels and cryogels

Scientific Reports , Article number:  (2026) Cite this article

We are providing an unedited version of this manuscript to give early access to its findings. Before final publication, the manuscript will undergo further editing. Please note there may be errors present which affect the content, and all legal disclaimers apply.

Subjects

Abstract

Bacterial cellulose (BC) pellicles were produced from Acetobacter xylinum using a simple, additive-free, and low-cost static cultivation method consistent with sustainable and green bioprocessing principles. Two post-synthesis drying routes were compared: supercritical carbon dioxide (scCO2) drying following acetone solvent exchange and direct lyophilization without chemical additives or pre-freezing. The resulting BC aerogels and cryogels were characterized by SEM, confocal microscopy, BET analysis, FTIR spectroscopy, EDS, and geometrical evaluation with a particular emphasis on nanostructure, porosity, and network integrity. scCO2-dried BC aerogels exhibited a well-preserved three-dimensional nanofibrillar network, achieving a BET surface area (123 m2/g), large pore volume (0.36 cm3/g), and an average pore diameter of 10 nm. Confocal microscopy revealed higher surface roughness (Rz up to ~ 58 μm), reflecting a more developed and heterogeneous surface topography. Lyophilized BC cryogels showed lower surface area (51 m2/g) and pore volume (0.13 cm3/g); however, SEM and confocal analyses indicated that the nanofibrillar network and three-dimensional architecture were largely retained, with only localized fibril aggregation and reduced roughness (~ 28–30 μm). EDS confirmed high chemical purity in scCO2-dried aerogels, while minor inorganic traces detected in cryogels were attributed to residual components from the tea-based culture medium. Although scCO2 drying provided slightly superior structural preservation and textural properties, the porous architecture remained comparable between the two methods. Overall, additive-free BC pellicles produced by static cultivation and processed via limited pre-freezing followed by lyophilization provided a structurally comparable and more sustainable alternative, offering a practical balance between textural performance and processing simplicity. These findings underscore the potential of simplified drying strategies for the sustainable fabrication of BC-based porous materials without compromising structural functionality.     .

Data availability

The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding authors.

References

  1. Eslahi, N. et al. Processing and Properties of Nanofibrous Bacterial Cellulose-Containing Polymer Composites: A Review of Recent Advances for Biomedical Applications. Polym. Rev. 60, 144–170. https://doi.org/10.1080/15583724.2019.1663210 (2020).

    Google Scholar 

  2. Gorgieva, S. & Trček, J. Bacterial Cellulose: Production, Modification and Perspectives in Biomedical Applications. Nanomaterials (Basel). 9, 1352. https://doi.org/10.3390/nano9101352 (2019).

    Google Scholar 

  3. Sozcu, S. et al. Effect of Drying Methods on the Thermal and Mechanical Behavior of Bacterial Cellulose Aerogel. Gels 10, 474. https://doi.org/10.3390/gels10070474 (2024).

    Google Scholar 

  4. Baraka, F., Ganesan, K., Milow, B. & Labidi, J. Cellulose nanofiber aerogels: effect of the composition and the drying method. Cellulose 31, 9699–9713. https://doi.org/10.1007/s10570-024-06191-2 (2024).

    Google Scholar 

  5. Ruan, J-Q. et al. Effects of Freeze-Drying Processes on the Acoustic Absorption Performance of Sustainable Cellulose Nanocrystal Aerogels. Gels 10, 141. https://doi.org/10.3390/gels10020141 (2024).

    Google Scholar 

  6. Zhang, X., Yu, Y., Jiang, Z. & Wang, H. The effect of freezing speed and hydrogel concentration on the microstructure and compressive performance of bamboo-based cellulose aerogel. J. Wood Sci. 61, 595–601. https://doi.org/10.1007/s10086-015-1514-7 (2015).

    Google Scholar 

  7. García-González, C. A. et al. Supercritical drying of aerogels using CO2: Effect of extraction time on the end material textural properties. J. Supercrit. Fluids. 66, 297–306. https://doi.org/10.1016/j.supflu.2012.02.026 (2012).

    Google Scholar 

  8. Wang, X. et al. Fabrication and characterization of nano-cellulose aerogels via supercritical CO2 drying technology. Mater. Lett. 183, 179–182. https://doi.org/10.1016/j.matlet.2016.07.081 (2016).

    Google Scholar 

  9. Das, R. et al. Nanocellulose for Sustainable Water Purification. Chem. Rev. 122, 8936–9031. https://doi.org/10.1021/acs.chemrev.1c00683 (2022).

    Google Scholar 

  10. Johnson, K. I. et al. Cellulose sulfate nanofibers for enhanced ammonium removal. Nanomaterials 14, 507. https://doi.org/10.3390/nano14060507 (2024).

  11. Sharma, S. K. et al. Nitro-oxidized carboxylated cellulose nanofiber based nanopapers and their PEM fuel cell performance. Sustainable Energy Fuels. 6, 3669–3680. https://doi.org/10.1039/D2SE00442A (2022).

    Google Scholar 

  12. Zhan, C. et al. Rice husk based nanocellulose scaffolds for highly efficient removal of heavy metal ions from contaminated water. Environ. Sci: Water Res. Technol. 6, 3080–3090. https://doi.org/10.1039/D0EW00545B (2020).

    Google Scholar 

  13. Chen, H. et al. Nitro-oxidized carboxycellulose nanofibers from moringa plant: effective bioadsorbent for mercury removal. Cellulose 28, 8611–8628. https://doi.org/10.1007/s10570-021-04057-5 (2021).

    Google Scholar 

  14. Sharma, P. R., Sharma, S. K., Lindström, T. & Hsiao, B. S. Nanocellulose-Enabled Membranes for Water Purification: Perspectives. Adv. Sustainable Syst. 4, 1900114. https://doi.org/10.1002/adsu.201900114 (2020).

    Google Scholar 

  15. Sozcu, S. et al. Synthesis of Acetobacter xylinum Bacterial Cellulose Aerogels and Their Effect on the Selected Properties. Gels 11, 272. https://doi.org/10.3390/gels11040272 (2025).

    Google Scholar 

  16. Lázár, I. & Fábián, I. A Continuous Extraction and Pumpless Supercritical CO2 Drying System for Laboratory-Scale Aerogel Production. Gels 2, 26. https://doi.org/10.3390/gels2040026 (2016).

    Google Scholar 

  17. Mao, N. 6—Methods for characterisation of nonwoven structure, property, and performance. In Advances in Technical Nonwovens (ed. Kellie, G.) 155–211 (Woodhead Publishing, 2016).

  18. Brown, C. A. Introduction to Surface Roughness Measurement—Olympus Device Roughness Measurement Guidebook, (2017). https://share.google/l6UJo3gAFdhfAC6q8.

  19. Lange, D. A., Jennings, H. M. & Shah, S. P. Analysis of surface roughness using confocal microscopy. J. Mater. Sci. 28, 3879–3884. https://doi.org/10.1007/BF00353195 (1993).

    Google Scholar 

  20. Rosentritt, M., Schmutzler, A., Hahnel, S. & Kurzendorfer-Brose, L. The Influence of CLSM Magnification on the Measured Roughness of Differently Prepared Dental Materials. Mater. (Basel). 17, 5954. https://doi.org/10.3390/ma17235954 (2024).

    Google Scholar 

  21. YL. Surface Roughness Parameters: Ra & Rz Calculation. In: IPQC-In Process Quality Control. (2023). https://www.ipqcco.com/blog/surface-roughness-parameters-calculation-how-to-determine-calculate-ra-rz. Accessed 11 Oct 2025.

  22. Hes, L. Thermal properties of nonwovens. In Proceedings of Congress Index (1987).

  23. Schwan, M. et al. Improvement of Solvent Exchange for Supercritical Dried Aerogels. Front. Mater. 8, 662487. https://doi.org/10.3389/fmats.2021.662487 (2021).

  24. Marchiori, L. et al. Effect of drying methods on the structure and properties of bacterial nanocellulose/MoS2 hybrid gel membranes and sphere-like particles for enhanced adsorption and photocatalytic applications. J. Sol-Gel Sci. Technol. 110, 635–653. https://doi.org/10.1007/s10971-024-06380-2 (2024).

    Google Scholar 

  25. McKenzie, J. S., Jurado, J. M. & de Pablos, F. Characterisation of tea leaves according to their total mineral content by means of probabilistic neural networks. Food Chem. 123, 859–864. https://doi.org/10.1016/j.foodchem.2010.05.007 (2010).

    Google Scholar 

  26. Hospodarova, V., Singovszka, E. & Stevulova, N. Characterization of Cellulosic Fibers by FTIR Spectroscopy for Their Further Implementation to Building Materials. Am. J. Anal. Chem. 9, 303–310. https://doi.org/10.4236/ajac.2018.96023 (2018).

    Google Scholar 

  27. Poletto, M., Ornaghi, H. L. & Zattera, A. J. Native Cellulose: Structure, Characterization and Thermal Properties. Materials 7, 6105–6119. https://doi.org/10.3390/ma7096105 (2014).

    Google Scholar 

  28. Wu, L. M. et al. Fourier transform infrared spectroscopy analysis for hydrothermal transformation of microcrystalline cellulose on montmorillonite. Appl. Clay Sci. 95, 74–82. https://doi.org/10.1016/j.clay.2014.03.014 (2014).

    Google Scholar 

  29. Mohanapriya Venkataraman, R. et al. Aerogel based high performance thermal insulation materials—IOPscience. IOP Conf. Ser. Mater. Sci. Eng. 553, 012043. https://doi.org/10.1088/1757-899X/553/1/012043 (2019).

  30. Samanta, A., Wang, Q., Shaw, S. K. & Ding, H. Roles of chemistry modification for laser textured metal alloys to achieve extreme surface wetting behaviors. Mater. Design. 192, 108744. https://doi.org/10.1016/j.matdes.2020.108744 (2020).

    Google Scholar 

  31. Liebner, F. et al. Aerogels from Unaltered Bacterial Cellulose: Application of scCO 2 Drying for the Preparation of Shaped, Ultra-Lightweight Cellulosic Aerogels. Macromol. Biosci. 10, 349–352. https://doi.org/10.1002/mabi.200900371 (2010).

    Google Scholar 

  32. Illa, M. P., Sharma, C. S. & Khandelwal, M. Tuning the physiochemical properties of bacterial cellulose: effect of drying conditions. J. Mater. Sci. 54, 12024–12035. https://doi.org/10.1007/s10853-019-03737-9 (2019).

    Google Scholar 

  33. Vasconcellos, V. & Farinas, C. The effect of the drying process on the properties of bacterial cellulose films from gluconacetobacter hansenii. Chem. Eng. Trans. 64, 145–150. https://doi.org/10.3303/CET1864025 (2018).

    Google Scholar 

  34. Machado, N. D., Goñi, M. L. & Gañán, N. A. Effect of supercritical CO2 drying variables and gel composition on the textural properties of cellulose aerogels. J. Supercrit. Fluids. 215, 106414. https://doi.org/10.1016/j.supflu.2024.106414 (2025).

    Google Scholar 

  35. Thommes, M. et al. Physisorption of gases, with special reference to the evaluation of surface area and pore size distribution (IUPAC Technical Report). Pure Appl. Chem. 87, 1051–1069. https://doi.org/10.1515/pac-2014-1117 (2015).

  36. Viktor V. Revin , Natalia B. Nazarova, Ekaterina E. Tsareva, Elena V. Liyaskina, Vadim D. Revin, & Nikolay A. Pestov. Production of Bacterial Cellulose Aerogels With Improved Physico-Mechanical Properties and Antibacterial Effect, Frontiers in Bioengineering and Biotechnology, https://doi.org/10.3389/fbioe.2020.603407 (2020).

Download references

Acknowledgements

The author gratefully acknowledges the HUN-REN-DE Mechanisms of Complex Homogeneous and Heterogeneous Chemical Reactions Research Group at the University of Debrecen for their assistance with the supercritical CO2 drying process carried out in this research.

Funding

This work is funded by the Department of Material Engineering, Faculty of Textile Engineering, Technical University of Liberec, Czech Republic.

Author information

Authors and Affiliations

  1. Department of Material Engineering, Faculty of Textile Engineering, Technical University of Liberec, 46117, Liberec, Czech Republic

    Şebnem Sözcü, Jakub Wiener, Jaroslava Frajová, Mohanapriya Venkataraman, Blanka Tomková & Jiří Militký

  2. HUN-REN-DE Mechanisms of Complex Homogeneous and Heterogeneous Chemical Reactions Research Group, Department of Inorganic and Analytical Chemistry, University of Debrecen, Egyetem tér 1, Debrecen, H-4032, Hungary

    József Kalmár & Attila Forgács

Authors

  1. Şebnem Sözcü
  2. Jakub Wiener
  3. Jaroslava Frajová
  4. Mohanapriya Venkataraman
  5. Blanka Tomková
  6. József Kalmár
  7. Attila Forgács
  8. Jiří Militký

Contributions

Conceptualization, S.S. and M.V.; methodology, S.S., J.W., and J.F.; software, S.S.; validation, S.S., B.T., J.W., J.K., A.F., and M.V.; formal analysis, S.S.; investigation, S.S. and M.V.; resources, S.S., J.W., and J.F.; data curation, S.S.; writing—original draft preparation, S.S.; writing—review and editing, M.V., J.K., A.F., J.W., and J.M.; visualization, J.W., B.T. and M.V.; supervision, M.V., J.M. and B.T.; project administration, M.V.; funding acquisition, M.V. All authors have read and agreed to the published version of the manuscript.

Corresponding authors

Correspondence to Şebnem Sözcü or Mohanapriya Venkataraman.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Sözcü, Ş., Wiener, J., Frajová, J. et al. Effect of drying methods on Acetobacter xylinum bacterial cellulose aerogels and cryogels. Sci Rep (2026). https://doi.org/10.1038/s41598-026-42244-1

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1038/s41598-026-42244-1

Keywords

Related Posts