This title appears in the Scientific Report : 2013 

Microwire crossbar arrays for on-chip localized thermal lesion of cell cultures
Rinklin, Philipp (Corresponding author)
Afanasenkau, Dzmitry / Wiegand, Simone / Wolfrum, Bernhard
Jülich-Aachen Research Alliance - Fundamentals of Future Information Technology; JARA-FIT
Bioelektronik; ICS-8
Bioelektronik; PGI-8
Weiche Materie ; ICS-3
NanoBioTech Montreux, Montreux (Switzerland), 2013-11-18 - 2013-11-20
Structural Biology
Sensorics and bioinspired systems
Physics of the Cell
Driven by an advance in microfabrication technologies, the development of miniaturized analytical platforms has become a major interest in physical, chemical, and biological research over the past two decades. On one hand, these systems offer the possibility to massively decrease the amount of resources and time necessary for current point-of-care medical diagnostics. On the other hand, the possibility to interact with biological systems in a highly controlled and easily parallelizable manner offers many promising opportunities for fundamental biological and biophysical research. For example, when studying the healing process of complex tissues after lesion, the use of simplified in vitro models can help to elucidate basic mechanisms. In this context, a means to create these lesions with high spatial control and resolution is of great importance. While the use of lasers coupled to microscopes is capable of delivering the necessary control and resolution, the requirement of external optics renders an application to on-chip devices difficult. Here, we demonstrate the use of microwire crossbar chips for the generation of localized thermally induced lesions in on-chip tissue models. Our chips consist of two orthogonal layers of parallel microwires, insulated from the culture medium by a polyimide layer. Cardiomyocyte-like HL-1 cells are cultured on the chip as an in vitro tissue model. Passing an electrical current through a given set of microwires leads to thermal heating of the active wires, which consequently imposes a localized stress on the cells cultured at the chip’s surface. We demonstrate that using this method, complex lesion patterns with a resolution in the lower micrometer regime can be created. The success of the lesion as well as the effects on the surrounding cells are evaluated using Calcein/EtHD staining methods. We further analyze the distinct Ca2+ propagation inside the cell layer revealing partially decoupled network activity depending on the applied lesion patterns. In conclusion, we believe that our method can be used as a versatile tool to study tissue lesions in simplified model systems. As a chip-based method, it also allows for low-cost production, as well as straight-forward inclusion in microsystems, which facilitates high-throughput and the generation of statistically relevant data from biological systems prone to high noise levels.