Understanding Mesoscale Structural Features of Bacterial Cellulose for Biomedical Applications

Bacterial cellulose (BC) is a renewable, biocompatible polymer with exceptional mechanical properties, high water-holding capacity, and can create tunable 3D network structures, making it a promising material for sustainable biomedical applications, particularly in wound care. The hierarchical organization of BC, from nanofibrils to mesoscale networks, is strongly influenced by the growth conditions, particularly the type of carbon source used during biosynthesis. Despite its versatility, there is a gap in understanding the precise mechanisms that dictate the formation and assembly of these fibrils into 3D networks. This study focuses on elucidating how growth conditions affect BC’s mesoscale structure, including fiber alignment and network density, as well as fiber-level ultrastructure and crystallinity. By investigating the fiber and fiber network features at different scales, we aim to bridge this knowledge gap and provide insights into how nanoscale fibrils aggregate and form interconnected networks. BC production was monitored through daily measurements of optical density and pH levels in the fermentation media from day 1 to day 14, providing valuable insights into bacterial growth and cellulose synthesis rates. Using techniques such as scanning electron microscopy (SEM) and wide-angle X-ray scattering (WAXS), we characterize the fibril morphology and crystallinity across varying carbon sources, including glucose, arabinose, sucrose, raffinose, and glycerol. The results emphasize the versatility and sustainability of BC as a platform for both wound healing and drug delivery applications, where its tunable network properties allow for the optimization of mechanical strength, porosity, and controlled drug release. We validate BC as an effective material for advanced wound management strategies, offering improved therapeutic delivery while addressing critical clinical and environmental needs.