Cargo-selective membrane transport with DNA nanopores

This project deals with molecular transport processes that play an important role in biology and biotechnology. Transport across membrane barriers occurs when biomolecules are shuttled out of or into biological cells or when pharmaceutical compounds are purified with porous filtration membranes. The transport process studied in the project is mediated via small pore with a width of a few nanometers. Movement of molecules through these small openings is unique and different to microscale or macroscale systems in several ways. First, a pore with a narrow opening can impose a size limit for molecule to be transported. Second, inside a pore, a biomolecules can be spatially confined and temporarily captured. Third, the small length scale can lead to frequent interactions between the biomolecule and the pore wall. The transport type studied in this project is also unique in that the pores carry internal nanoscale affinity tracks. The tracks specifically recognize molecular cargo and thereby enable that only target molecules can pass the pore. Our project will provide a step-change in understanding of this transport process. It will overcome the current shortage of knowledge of how pore dimensions influence how fast or how specific molecules are transported. To realize the projects aim, our approach will combine experiments and mathematical simulations. We expect that our new scientific insight will help in the rational design of nanoporous purification membranes or nanopore-based devices such as biosensors.

This project has explored molecular transport processes that play an important role in biology and biotechnology. Transport across membrane barriers occurs when biomolecules are shuttled out of or into biological cells or when pharmaceutical compounds are purified with porous filtration membranes. The transport process studied in the project was mediated within small hollow pore of a width of a few nanometres. Movement of molecules through these small openings is unique and different to microscale or macroscale systems in several ways. (i) A pore with a narrow opening can impose a size limit for molecule to be transported. (ii) Inside a pore, biomolecules can be spatially confined and temporarily captured. (iii) The small length scale can lead to frequent interactions between the biomolecule and the pore wall. The transport type studied in this project was (iv) also unique in that the pores carry internal nanoscale affinity tracks. The tracks specifically recognize molecular cargo and thereby enable that only target molecules can pass the pore. To drastically improve these transport processes, our project has created the nanoscale pores of tuneable size and equipped them with affinity tracks. The passage of cargo was also followed via single-molecule analysis. Furthermore, a mathematical model of cargo transport was developed to generalise the experimental findings. Our new scientific insight will help in the rational design of nanoporous purification membranes or nanopore-based devices such as biosensors.