Photoresist Micro-Chamber for the Diffracted X-ray Tracking Method Recording Single-Molecule Conformational Changes

Abstract

The diffracted X-ray tracking method has been established for capturing conformational changes of single KcsA potassium channels, which records position of X-ray diffraction spot from a gold nanocrystal attached to the channel. The conventional observation chamber setup could trace a diffraction spot; however relatively high background noise resulting from X-ray scattering degraded a spatial resolution. This paper report a novel low-noise microfabricated observation chamber consisting of SiN membrane window supported by Si and embedded microchannel in negative photoresist. The measured noise exhibited lower level compared to the conventional chamber, which almost reached the detection limit of the employed imaging system.