Analysis of Hydrogel Matrices using Advanced Electron Microscopy

Complex wounds are a global health problem with significant impact on the health care economy. In developed countries alone, they impact the quality of life of more than 2% of total population.
Complex wounds, including chronic wounds or major burns, are highly susceptible to microbial infection and are difficult to treat. The EU NABIHEAL project aims to develop multifunctional biomaterials
for treatment of wound infections, prevention of complications during wound healing, and providing improved wound management. For this purpose, hydrogel matrices of different composition and
structure will be used. Here we demonstrate the characterization of some of these hydrogel matrices, using complementary high-resolution scanning electron microscopy (HR-SEM) techniques. SEM
methods scan the surface of the specimen and provide valuable information on the topography at different length scales, and composition. Most SEM characterization is done with dry samples, but
analyzing hydrated gels at low temperatures can further unfold the inner 3D structure, pore size distribution and other characteristics of the sample. We here combine structural insight from classical
SEM (dry-SEM), environmental-SEM (E-SEM) that allows ambient humidity by adjusting the chamber pressure and temperature, and Cryogenic-SEM (Cryo-SEM) where the samples are prepared in the
wet state and examined at low temperatures.