Contact

Zumdick, Naemi M.Sc.
Corrosion and corrosion protection
Chair for comprehensive corrosion and corrosion protection

Tel.: +49 (0)241 80-95900
n.zumdick@gi.rwth-aachen.de

Metals for biomedical engineering

Degradable magnesium alloys as well as permanent implants of Ti alloys are only two examples of materials specifically enhanced for applications in biomedicine. Here, research work is focussing on functionalising surfaces to improve cell and protein adhesion as well as developing biocompatible, corrosion-optimized alloys. A basic understanding of interfacial reactions in complex organic and inorganic electrolyte systems serves as the basis for further developing so-called “artificial simulated body fluids” for in-vitro testing methods. In this way, material behaviour can be simulated, particularly with regard to corrosion.

Magnesium as a biodegradable implant material

The research activities at the KKS focus on the ex-situ and in-situ analysis of the microstructural and corrosion properties of biodegradable magnesium alloys. This class of materials is a very promising candidate for employing as temporary implants since their mechanical and physical properties resemble those of human bone and are, moreover, biocompatible. The aqueous corrosion of magnesium is exploited in order to manufacture an implant which degrades in the human body leaving as little residue products as possible.  In this way, post-healing surgical procedures to remove the implants are eliminated.

A current challenge in alloy design involves employing only non-toxic elements to reduce the magnesium alloy’s degradation rate in the human body. Here, the degradation properties are essentially influenced by the microstructure, the alloying elements as well as the manufacturing process. Besides conventional analytical methods and degradation testing, 3D-synchrotron characterisations are currently carried out. In addition to this, the main focus of attention is a basic understanding of interfacial reactions in complex organic and inorganic electrolyte systems. This is essential for enhancing the corrosion testing cells and solutions, and serves to optimally correlate in-vitro and in-vivo test results.

Titanium

Current research shows that superposed nano-structures on micro-topographies improves the general biocompatibility of permanent biomaterials. By using redox reactions in combination with corrosion processes, different nano-structures can be specifically manufactured on the titanium. Current research is aimed at evaluating the mechanisms, on which this nano-structuring is based, and at producing these on low Young’s modulus β-titanium. Ongoing investigations use redox solutions, which are composed of endogenous components, to ensure subsequent biocompatibility. In conjunction with the University Clinic of the RWTH Aachen, whole-cell reactions on the manufactured nano-surfaces are also analysed.