To overcome this, the scientists chemically attached to the DNA tube two large anchors, made of molecules which have a natural affinity for lipids. These structures were then able to embed the tube into the membrane. These structures, which are based on naturally derived porphyrins, were designed by a group led by Dr Eugen Stulz (University of Southampton).
"Porphyrin molecules have ideal characteristics for our purposes," Stulz explains. "They are a strong membrane anchor, which locks the nanopore securely into the lipid membrane. In addition, they are fluorescent, which means they are easy to see and study. This makes them superior to other technologies."
The pores were characterised with electrical and fluorescence measurements in collaboration with Dr Ulrich Keyser (Cavendish Laboratory, Cambridge).
The simplicity of self-assembling a structure with only two anchors (previous studies used 26 or even 72 such anchors) greatly streamlines the design and synthesis of nanopores.
"In future, this new process will enable us to tailor DNA nanopores for a much wider range of applications than are currently possible," Keyser says.
The ability to create synthetic channels through lipid membranes enables numerous applications in the life sciences. In the first instance, DNA nanopores are of great interest for biosensing, such as rapid DNA analysis.
But tailored pores can also be expected to aid the development of new drugs. Prototype drugs are typically designed to affect a biological target, but are not engineered to cross the cell membrane. Self-assembled
|Contact: Clare Ryan|
University College London