Extended Data Fig. 4: Workflow for DNA nanoballs (DNBs) loading onto nanowells of biochip and DNA sequencing.
From: Fast, cost-effective and flexible DNA sequencing by roll-to-roll fluidics
a, Negatively charged DNBs from solution selectively adhere onto positively charged attachment points on the biochip, forming the DNBs array for sequencing. b, A picture of a biochip (7 cm × 7 cm) containing an array of positively charged nanowells and negatively charged DNBs (diameter ~220 nm, same as the nanowell). c, Atomic force microscopic study of the biochip surface before and after loading. Left panels show top view and sampling positions, and right panels show height profiles. After loading and dehydration, the DNBs’ height shrinks to 5 nm and are protected by the donut shape of the nanowell edges. d, Depictions of a layer of wash buffers flushing unbonded DNBs from the biochip surface, resulting in a completely loaded biochip as shown in (e). f, Depiction of a self-termination reaction for sequencing that single DNA strand extension by one dATP. See also Supporting Video 2.
