Since the introduction of coronary stents in the mid-1980s, medical engineering on stents considerably improved treatment of coronary artery disease but is still facing various complications including in-stent restenosis and subacute thrombosis [1]. Rapid endothelization of the implant is considered the solution for stent induced issues as its natural layer acts antithrombogenic and restrains hyperplasia [2]. However, stent design regarding the promotion of a healthy endothelium still represents a challenge in medical and surface engineering.

Current research focusses on the topographical modification of the implant’s surface to enhance adhesion and proliferation of endothelial cells (ECs) while reducing the adhesion of smooth muscle cells as well as the activation of platelets. While approaches applying grooves, pillars, porous structures and nanowires in micro- and nano-scale already pointed out advantageous effects on cells [3,4], Direct Laser Interference Patterning (DLIP) offers a powerful tool to create a variety of surface patterns on a broad range of materials [5]. By using ultrashort laser pulses, also hierarchical structures can be created and investigated regarding the required cell- and platelet-interaction [6].

The presented project aims to design implant surfaces for increased hemocompatibility for infant patients by combining preferential surface topography and chemistry modifications. The initial work involves the applications of periodic surface patterns of different scales by ultra short-pulse-DLIP on CoCr model surfaces, followed by topographic and chemical characterization via LSM, FIB/SEM, EDX and XRD. In application-oriented experiments, the surface patterns will be tested regarding their hemocompatibility as well as their biocompatibility on different cell types from the cardiovascular system. A comparison of the surface properties with the cell response will give a better insight in the cell-surface interaction and point out the most suitable DLIP structure for further surface development in this particular infant related field of cardiovascular treatment.

References

[1] S. Garg, P.W. Serruys, Coronary Stents: Current Status, J Am Coll Cardiol. 56 (2010). https://doi.org/10.1016/J.JACC.2010.06.007.

[2] J. Li, K. Zhang, N. Huang, Engineering Cardiovascular Implant Surfaces to Create a Vascular Endothelial Growth Microenvironment, Biotechnol J. 12 (2017) 1600401. https://doi.org/10.1002/biot.201600401.

[3] J. Dong, M. Pacella, Y. Liu, L. Zhao, Surface engineering and the application of laser-based processes to stents - A review of the latest development, Bioact Mater. 10 (2022) 159–184. https://doi.org/10.1016/j.bioactmat.2021.08.023.

[4] R. Schieber, C. Mas-Moruno, F. Lasserre, J.J. Roa, M.P. Ginebra, F. Mücklich, M. Pegueroles, Effectiveness of Direct Laser Interference Patterning and Peptide Immobilization on Endothelial Cell Migration for Cardio-Vascular Applications: An In Vitro Study, Nanomaterials. 12 (2022). https://doi.org/10.3390/nano12071217.

[5] A.F. Lasagni, Laser interference patterning methods: Possibilities for high-throughput fabrication of periodic surface patterns, Advanced Optical Technologies. 6 (2017) 265–275. https://doi.org/10.1515/aot-2017-0016.

[6] S. Alamri, F. Fraggelakis, T. Kunze, B. Krupop, G. Mincuzzi, R. Kling, A.F. Lasagni, On the Interplay of DLIP and LIPSS Upon Ultra-Short Laser Pulse Irradiation, Materials. 12 (2019) 1018. https://doi.org/10.3390/ma12071018.