Human autologous bioengineered skin has been successfully developed and used to treat skin injuries in a growing number of cases. In current clinical studies, the biomaterial used is fabricated via plastic compression of collagen hydrogel to increase the density and stability of the tissue. To further facilitate clinical adoption of bioengineered skin, the fabrication technique needs to be improved in terms of standardization and automation. Here, we present a one-step mixing technique using highly concentrated collagen and human fibroblasts to simplify fabrication of stable dermal equivalents. As controls, we prepared cellularized dermal equivalents with three varying collagen compositions. We found that the dermal equivalents produced using the simplified mixing technique were stable and pliable, showed viable fibroblast distribution throughout the tissue, and were comparable to highly concentrated manually produced collagen gels. Because no subsequent plastic compression of collagen is required in the simplified mixing technique, the fabrication steps and production time for dermal equivalents are consistently reduced. The present study provides a basis for further investigations to optimize the technique, which has significant promise in enabling efficient clinical production of bioengineered skin in the future.
This paper presents a design approach, based on the idea to develop a product that allows a considerably faster diagnose of bacterial infections in the physicians office and thus, supports avoiding the unnecessary use of antibiotics. Nowadays, physicians send probes to central labs for diagnoses. These Labs usually use either manual work or microfluidic platforms. Most microfluidic platforms require expensive machinery for realizing complex motion sequences. However, there also is a costefficient alternative: centrifugal microfluidic platforms, which are also known as ‘lab-on-a-disk’. In order to control flows, these disks take advantage of centrifugal forces, which can be easily regulated via rotation speed. In a first step, the technical feasibility was investigated with focus on basic designs of centrifugal microfluidic platforms for reliable controlling flows, only by regulation of rotation speed. The channel and reservoir designs were evaluated based on the results gained by physical testing of a lab-on-a-disk prototype in operation. The results and implications support the further development of a fully automated diagnostic device to be used as point-of-care.
