Abstract
The extracellular matrix (ECM) is comprised of components like collagen, elastin, and glycosaminoglycans (GAGs). Electrospun fibrous scaffolds are designed to replicate the form and composition of the native ECM, often requiring blending of various ECM component mimics to enhance cellular responses. However, the spatial distribution of blended components within these fibers remains unclear. This study investigates the spatial distribution of chondroitin sulfate-C (CSC) in electrospun gelatin-based scaffolds. scanning electron microscopy (SEM), attenuated reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and Time-of-flight Secondary Ion Mass Spectrometry (ToF-SIMS) were applied for surface and subsurface chemical characterization of the fibrous scaffolds. SEM confirmed a fibrous morphology, while ATR-FTIR and XPS analyses indicated the presence of CSC through the identification of sulfate groups. ToF-SIMS imaging, alongside K-means clustering and Ripley’s K function, revealed a nonuniform CSC distribution with higher concentrations at the top layer of the scaffold. This study demonstrates that CSC presentation at the fiber surface varies with depth and differs from bulk incorporation while reveals nanoscale clustering and spatial heterogeneity at both the surface and subsurface of electrospun gelatin fibers. These findings define an underexplored design consideration with potential to influence cell-scaffold interactions.
| Original language | English |
|---|---|
| Pages (from-to) | 25405-25414 |
| Number of pages | 10 |
| Journal | ACS Omega |
| Volume | 10 |
| Issue number | 24 |
| DOIs | |
| State | Published - Jun 24 2025 |
Funding
We thank Huafang Li at the Institute for Materials Science and Engineering at Washington University for her kind help with the XPS and SEM data acquisition. We would also like to thank the Chemical and Environmental Analysis Facility (CEAF) at Washington University in St. Louis for providing the FTIR equipment. ToF-SIMS characterization was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility, and using instrumentation within ORNL’s Materials Characterization Core provided by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. We would like to thank support from the Center for Engineering Mechanobiology (CEMB), an NSF Science and Technology Center, under grant agreement CMMI: 15-48571 and the National Institutes of Health (NIH) R01AR077056. We thank Huafang Li at the Institute for Materials Science and Engineering at Washington University for her kind help with the XPS and SEM data acquisition. We would also like to thank the Chemical and Environmental Analysis Facility (CEAF) at Washington University in St. Louis for providing the FTIR equipment. ToF-SIMS characterization was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility, and using instrumentation within ORNL’s Materials Characterization Core provided by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. We would like to thank support from the Center for Engineering Mechanobiology (CEMB), an NSF Science and Technology Center, under grant agreement CMMI: 15-48571 and the National Institutes of Health (NIH) R01AR077056.