Fig. 2: Quantifying dCas9 binding to the nanostructures.

a, dCas9 probes and DNA nanostructures overhang schematics depicting single base difference between sequences in crRNA probe (with the PAM in red) and DNA overhang. The single base-pair change can be found in Kat315 gene in isoniazid-resistant Mycobacterium tuberculosis. Two different DNA nanostructures with different overhangs (green and purple) are depicted. b, Binding specificity of the probes when both DNA nanostructures are added and only one respective probe is added. N > 65 events for each experiment. A control nanostructure with target DNA containing no PAM was also tested as seen in grey, where N > 165. Calculations were made using equations (1) and (2). c, Quantification of labelled events dependent on varying relative concentration ratio of DNA nanostructures (green or purple) in solution with equimolar concentrations of the two dCas9 probes (standard deviation represents one sample measured in at least two different pores). Calculations were made using equations (3–6). N > 85 events for each condition. Error bars represent standard deviation between nanopores. d, Reproduced experiments with 11001 and 11111 nanostructures barcode at a ratio of 2:1 in solution with equimolar concentrations of both dCas9 probes added. The different bars (1, 2 and 3) are three independent sample preparation repeats in three different nanopores. Calculations were made using equations (3–6). N > 100 events for each measurement. In all experiments, dCas9 probes were added in excess to target DNA molecules.