20 bp dna ladder

The IdentiClone™ B-Cell Clonality Assay kit was purchased from Invivoscribe Technologies. The 20 bp DNA ladder and 10× loading buffers were purchased from Takara. GelRed dye was purchased from BioTium, AmpliTaq Gold DNA polymerase from ABI, and DNA FFPE Tissue Kit from Xiamen Aide Biomedicine Limited.

Sgc8 was prepared as a 1 μM solution in 20 mM Tris-HCl buffer (pH 7.4, containing 100 mM NaCl and 2 mM MgCl₂) and mixed with 0.09 mg/mL GIAN for 30 min prior to the addition of Sgc8-H. Then Sgc8-H was added to the prepared GIAN-Sgc8 solution, and about 15 min was allowed for hybridization at 37°C. Finally, the fluorescence of Sgc8-FAM, GIAN-Sgc8-FAM and GIAN-Sgc8-FAM/Sgc8-H was detected with a fluorescence analyzer, and aptamer functionalization efficiency was investigated with gel electrophoresis. After the samples were loaded, a 1 × TBE buffer as running solution was added into the outer buffer reservoir until the liquid level just covered the top surface of the gel. A 20 bp DNA Ladder (TaKaRa, China) was added in the first lane as the molecular weight size marker. Ethidium bromide dyes (Dingguo Changsheng Ltd., China) were added to stain the nucleic acids. The electrophoresis was run at a constant bias of 120 V. For targeted cell imaging, HeLa and 95-C cells were cultured in a 30-mm glass bottom dish with 2 mL media for one day. After cells were washed, GIAN and GIAN-Sgc8 were added to the cell wells, and the cells were incubated for 2 hours at 4°C. The cells were then carefully rinsed two times, followed by analysis using a FV1000-X81 confocal microscope (Olympus) equipped with a 60× objective with an 850 nm excitation laser.

The formation of tripodna, CpG1668/tripodna, and SA-CpG1668/tripodna was confirmed by PAGE (6%), which was carried out at 200 V for 30 min at approximately 4 °C. A total of 100 ng of each DNA sample was added to the gel. The 20 bp DNA ladder was purchased from TaKaRa (Tokyo, Japan).