Team:Hong Kong HKU/Nanostructure Synthesis
Nanostructure Synthesis
Therapeutic Nano Drug Carrier (NDC) structural characterisation
The sizes of the 4 ssDNA component strands are shown in lanes 2-5 (from left to right). We confirmed the successful annealing of our DNA tetrahedron on lanes 6-8 in a stepwise manner when adding up ssDNA.
The sizes of the 4 ssDNA component strands are shown in lanes 2-5 (from left to right). The strands are 1) Strand 1-ST1; 2) Strand 2-APT33; 3) Strand 3-AS1411 and 4) Strand 4-SYL3C. We confirmed the successful annealing of our DNA tetrahedron on lanes 6-8 in a stepwise manner when adding up ssDNA.
Our DNA tetrahedral structures are stained and visualised by a Philips CM 100 Transmission Electron Microscope with 100 kV operating voltage.
Since the 3' end of each strand is modified to have a thiol group, gold nanoparticles could then be attached to it. After the strands assemble, all four vertices of the final tetrahedron will be attached by a gold nanoparticle and could be observed under the Transmission Electron Microscope.
In Vivo Synthesis in E. Coli
The strands was synthesised by the ETHERNO system, an E. coli-driven in vivo ssDNA synthesis system we developed last year. The first eight lanes contain duplicates of each strand amplified by a strand-specific forward primer and a backbone-specific reverse primer. The remaining lanes are duplicates of each strand amplified by a backbone-specific forward primer and a strand-specific reverse primer.
The strands was also synthesised by the ETHERNO system and another method was used to verify them. Strand 4 is tagged by a fluorophore and annealed with the other strands. Since all strands combine together and form a tetrahedron, each strands could complementarily bind to each other. Lane 2, 3, 5 and 7 are ssDNA and lane 4, 6 and 8 are different strands annealed to strand 4. The size confirms the successful synthesis of the ssDNA.