Bone cells cellular microarrays on fibronectin micropatterns in microwells of microfluidic chips

A recent method to create micropatterns is pen nanolithography, which is an atomic force microscopy (AFM)-based lithography technique. Micropatterns for cell adhesion (Sekula et al., 2008) can be fabricated with a feature size down to appr. 15 μm (Wu et al., 2011). The advantage of this method is that micropatterns can be written in microwells, which can be organized in an array in a microfluidic chip for high-throughput screening. Conventional ink jet methods will not allow for spot sizes that are in the desired size range for microwell printing. Printing techniques like microcontact printing (μCP) will encounter geometrical constrains when trying to print on the bottom of the well structure. In this work, we initiated the evaluation of pen lithography for the single-cell adhesion and growth of bone cells (osteocytes) in microwells of microfluidic chips.