Date of Award

Fall 9-2016

Embargo Period


Degree Type

Dissertation (CMU Access Only)

Degree Name

Doctor of Philosophy (PhD)


Biomedical Engineering


Christopher J. Bettinger


Percutaneous devices are necessary tools in modern healthcare. More than one hundred fifty million percutaneous catheters have been purchased annually for various medical procedures, such as blood monitoring, urine drainage, and drug administration. However, catheter-related bloodstream infections occur in a high rate, up to 250,000 cases each year, and lead up to 25% mortality rate. One of the key causes is the skindevice incompatibility. It contributes to chronic inflammation and skin migration that generates a deep gap around the device. The lack of body outer barrier in such small area is ample for bacteria that accumulate near the insertion site to penetrate into the blood system, leading to a high risk of infections. Engineering of physical, chemical, and mechanical properties of percutaneous biomaterials is promising to improve host responses and ultimately prevent the infections. In this study, we design percutaneous biomaterials using three main approaches, i.e. surface topography, macrophage modulation, and protein-adsorption resisting materials, to attenuate the dermal downgrowth. The material in each design is characterized in in vitro environments to obtain physical, chemical, and mechanical properties, and also in in vivo milieu using a mouse model to profoundly investigate host responses. This work provides an insight of promising percutaneous material designs that reduce catheter-related complications and infections.