Fig. 2

RCT reaction system optimization and NFs characterization. A Different concentration ratios of template and primer were used to perform the hybridization and ligation reactions. Lane M: DNA ladder, from top to bottom: 500 bp, 400 bp, 300 bp, 200 bp, 100 bp, 80 bp, and 20 bp; lanes 1–3: template to primer concentration ratios of 1:1, 1:2, and 1:3. B Various ligases were used for amplification. Lane M: DNA ladder, from top to bottom: 15 kb, 1 kb, 7500 bp, 5000 bp, 2500 bp, 1000 bp, and 250 bp; lane 1: Taq DNA ligase was used; lane 2: T4 DNA ligase was used. C–E Products amplified with different hybridization times and ligation times. Lane M: DNA ladder, from top to bottom, 15 kb, 1 kb, 7500 bp, 5000 bp, 2500 bp, 1000 bp, and 250 bp; C lanes 1–3: hybridization time 1 h, ligation time: 1 h, 2 h, 3 h. D Lanes 1–3: hybridization time 2 h, ligation time: 1 h, 2 h, 3 h. E Lanes 1–3: hybridization time 3 h, ligation time: 1 h, 2 h, 3 h. F Different concentrations of rNTPs were used for transcription. Lane M: DNA ladder, from top to bottom: 15 kb, 1 kb, 7,500 bp, 5,000 bp, 2,500 bp, 1,000 bp, and 250 bp; lanes 1–5: rNTP concentrations of 2 mM, 4 mM, 6 mM, 8 mM, and 10 mM. G, H Amplification products before and after rolling circle transcription system optimization. Lane 1: RNA; lane M: DNA ladder. I, J SEM images of the NFs