Front-of-Mind:- Biomaterials Meet Microfluidic Technology

Please share your views and opinions on where you see research opportunities relating to the integration of microfluidic technology for the synthesis of functional biomaterials, enabling drug discovery or therapeutic cell-based applications.

Cell biologists begin to appreciate the significance of biomaterials as tools for the study of stem cell proliferation and differentiation. The attention in biomaterials has increased mainly because of the new knowledge of the limitations of conventional cell culture techniques to control in vitro stem cell behaviour. Separated from tissue and exposed to a rigid and hydrophobic plastic cell culture surface, many adult stem cell types quickly lose their multipotent properties. The stem cells live in highly hydrated and soft niches in vivo , which fix the stem cell to its anatomical location in tissue and offer instructive cues that needed in order to regulate fate. Niches are typically composed of crosslinked extracellular matrices rich in sugars and proteins, in addition, to supporting cells that secrete soluble signalling cues and provide crucial cell-cell interactions. The niche-dependency of stem cell fate therefore requires in vitro environments that provide the key biochemical signals needed to be presented in a tissue-specific, biophysically relevant context.

Indeed, more recent biomaterial innovations can be tailor-made to replicate the in vivo environment of stem cells. Recent developments allow the synthesis and fabrication of soft polymers (e.g. hydrogel-based systems) with tunable mechanical properties, degradability and bioresponsiveness. However, in spite of these great scientific discoveries, many mammalian stem cells still cannot be cultured in vitro for a prolonged period without losing their proliferative capacity; it also still remains difficult for differentiation in a regulated manner, largely because of our capacity to control the spatial and temporal demonstration of biological signals to stem cells under in vitro conditions. Over the last number of years, there have been many research groups, including the Fraunhofer Project Centre for Embedded Bioanalytical Systems within the Biodesign Europe Institute at Dublin City University, are investigating ways to overcome this obstacle through the application of microfluidic systems for biomaterials design and modification.

A microfluidic system, namely, lab-on-a-chip , is a multifunctional platform that intertwines the basic operating units involved in the fields of chemistry and biology, such as sample preparation, reaction, separation, detection, and cell culture, separation, lysis, into a chip, within an area of a few square centimetres. In this system, the microstructure nature of the units and controllable fluidics constitute the network, which works as conventional chemical or biological laboratories. The idea of microfluidics fits well with the concept of miniaturisation, and thanks to its interdisciplinary advantages, it has been widely applied in fields such as engineering, physics, chemistry, microscopy, and biotechnology.

Also, microfluidic technology offers the advantages of large-scale integration and flexible manipulation. Accordingly, the field of microfluidics has been rapidly developed as one of the most important high-throughput platforms in the field of functional biomaterial synthesis and the development of more physiological representative models of stem cell niches that could facilitate the identification of new mechanisms of stem cell regulation, profoundly impacting drug discovery/functional biomaterials development and ultimately therapeutic stem cell applications. Compared to biomaterials assisted by conventional strategies, functional biomaterials synthesized by microfluidics are with superior properties and performances, due to their controllable morphology and composition, which have shown great advantages and potential in the field of biomedicine, biosensing, and tissue engineering. Additionally, microfluidics offers distinctive flow regime that allows the exact positioning of biomolecules and/or cells with well-defined dynamics. Consequently, this approach provides the opportunity to develop an array of miniaturised models of stem cell microenvironments or even tissues at different degrees of complexity.

Please share your views and opinions on where you see research opportunities relating to the integration of microfluidic technology for the synthesis of functional biomaterials, enabling drug discovery or therapeutic cell-based applications.