Monitoring cellular response to biomaterials

Abstract

Cellular response, and monitoring that response, is a widely studied field and includes cellular interactions with inorganic, organic, and biological materials [1]. For the most part, cellular response studies examine the proliferation, differentiation, function, and migration of cells in various environments [2]. Viability and proliferation can indicate a stable cellular system, but that is not always the case. This study examines a new method that could be employed to measure the concentration of molecules present in a cellular environment that could influence their behavior. The first part of this thesis examines the growth and differentiation of osteogenic cells on a bioglass product that was fabricated from recycled food waste products [3]. Multiple aspects of cellular response were monitored including their proliferation, viability, enzyme production, and mineral deposition while on the material and cultured under both standard and osteogenic conditions. Likely due to leaching of minerals from the bioglass product, the cellular differentiation response was difficult to interpret, and demonstrated that the microenvironments of the system needed to be taken into account. Thus, a new method for the detection of small molecules within a cell culture system was investigated to further study the cellular microenvironment, using pH-sensing nanofibers [5,6]. The second part of this thesis investigates the use of pH sensing nanofibers to observe the shift in pH of three dimensional hydrogel cell culture systems over time. E. coli was also introduced to the system to study how a simulated infection could cause a shift in pH and verify the response from the nanofibers. Throughout testing, the nanofibers performed as predicted, with an increase in fluorescence indicating a decrease in pH. This work sheds light on the observation of cellular responses to their microenvironment and develops a new tool that could be used to monitor cell culture systems.