Visualizing Nanostructures in Supramolecular Hydrogels: A Correlative Study Using Confocal and Cryogenic Scanning Electron Microscopy

Submitting author affiliation:
ICMAB, Cerdanyola del Vallès, Spain

Beilstein Arch. 2025, 202555. https://doi.org/10.3762/bxiv.2025.55.v1

Published 12 Sep 2025

Preprint
cc-by Logo
This preprint has not been peer-reviewed. When a peer-reviewed version is available, this information will be updated.

Abstract

Solvated supramolecular hydrogels present unique challenges in nanoscale morphological characterization because of their fragile fibrous nature and low concentration of the solid component. In this study, imidazolium-based hydrogels containing either diketopyrrolopyrrole (DPP) or zinc(II) phthalocyanine (ZnPc) fluorophores were imaged using confocal laser scanning microscopy (CLSM) of fully solvated gels and cryogenic scanning electron microscopy (cryo-SEM) of the corresponding xerogels. The DPP@Gel systems exhibit strong fluorescence and are effectively imaged using CLSM, with fibre morphologies that closely correlate with those seen with cryo-SEM. In contrast, the analogous imidazolium gel system containing a sulfonated zinc phthalocyanine (ZnPc@Gel) yields poor CLSM images because of the relatively weak emission and sample disruption during compression, whereas cryo-SEM enables clear visualization of the native fibrous network. These results demonstrate the complementary nature of CLSM and cryo-SEM and highlight the value of cryo-SEM as a very useful tool for imaging soft nanomaterials with low fluorescence or limited optical contrast.

Keywords: Anion binding; colloid; fluorophore; microscopies; nanostructure; supramolecular hydrogel

Supporting Information

Format: GIF Size: 9.2 MB   Download
Format: PDF Size: 361.0 KB   Download
Format: GIF Size: 15.2 MB   Download

How to Cite

When a peer-reviewed version of this preprint is available, this information will be updated in the information box above. If no peer-reviewed version is available, please cite this preprint using the following information:

Smith, S. M.; Malagreca, F.; Hicks, J.; Mantovani, G.; Amabilino, D. B.; Parmenter, C.; Pérez-García, L. Beilstein Arch. 2025, 202555. doi:10.3762/bxiv.2025.55.v1

Download Citation

Citation data can be downloaded as file using the "Download" button or used for copy/paste from the text window below.
Citation data in RIS format can be imported by all major citation management software, including EndNote, ProCite, RefWorks, and Zotero.

OTHER BEILSTEIN-INSTITUT OPEN SCIENCE ACTIVITIES