Streptavidin-magnetic beads (1 μm diameter, 4 mg mL−1, an aqueous suspension containing 0.1% bovine serum albumin, pH 7.4, 0.05% Tween-20, and 0.05% NaN3), nicking endonuclease (Nb.BbvCI) and 10× CutSmart™ buffer (20 mM, Tris-acetate, 500 mM potassium acetate, 10 mM magnesium acetate, and 100 μg mL−1 BSA, pH 7.9) were purchased from New England Biolabs (Beijing, China). Gold View I (GV I) (10 000×) used in this study was provided by Solarbio Co. Ltd. (Xiamen, China). The DL 200 DNA marker was ordered from Takara (Dalian, China). Salmon sperm DNA was obtained from Solarbio Inc. (Beijing, China). All oligonucleotides were synthesized and purified via HPLC by Sangon Biotechnology Co. Ltd. (Shanghai, China), and the corresponding sequences are illustrated in Table S1 (ESI).† All oligonucleotides were dissolved in tris-ethylenediaminetetraacetic acid (TE) buffer (pH 8.0, 10 mM Tris–HCl, 1 mM EDTA) and stored at −20 °C for further use.
Moreover, 0.1 M phosphate-buffered solution (PBS) included 136.89 mM NaCl, 2.67 mM KCl, 8.10 mM Na2HPO4 and 1.76 mM KH2PO4 (pH 7.4). The reaction buffer contained 10 mM Tris–HCl, 1 mM EDTA and 12.5 mM MgCl2 (pH 8.0). Other chemicals (analytical grade) were obtained from standard reagent suppliers. Millipore-Q water (≥18 MΩ, Milli-Q, Millipore) was used throughout the experiments.
Moreover, 0.1 M phosphate-buffered solution (PBS) included 136.89 mM NaCl, 2.67 mM KCl, 8.10 mM Na2HPO4 and 1.76 mM KH2PO4 (pH 7.4). The reaction buffer contained 10 mM Tris–HCl, 1 mM EDTA and 12.5 mM MgCl2 (pH 8.0). Other chemicals (analytical grade) were obtained from standard reagent suppliers. Millipore-Q water (≥18 MΩ, Milli-Q, Millipore) was used throughout the experiments.