Streptavidine spots printed on a BALM surface. The thickness of the protein layer is expected to be 3 nm.

First image: notice the small size of the lower spots (5 µm), and the excess of deposited material.

Second image: same with large spots and higher contrast setting.

 

Images height = 100 µm (Credit: BALM: D. Ausserré, CNRS / Biochips printing: Innopsys / 2017 January)