Workshop on integration of DNA origami performed at University of Potsdam
Immobilisation of DNA origami is the main task of the DeDNAed project’s Work Package 5. To exploit knowledge and expertise, a workshop was organised at University of Potsdam, Germany from June 16 – 17th, 2022, by Saloni Agarwal and Prof. Frank Bier (University of Potsdam).
The integration of the DNA origami, which serves as a nano-bread for our biosensor, needs to be done on either solid or flexible surfaces. To begin, we used silicon-oxide as a solid surface for immobilisation. Micro and nano array chips were designed and produced using the thin film system at Technical University Chemnitz (TUC / Germany). DNA-origami is produced at the Kurt-Schwab-Institut für Mess- und Sensortechnik Meinsberg e.V. (KSI /Germany), and was received in certain concentrations of MgCl2, facilitating in accurate folding of the origami and even in the attachment of the origami to the surfaces.
The immobilisation of DNA-origami was studied in two ways: a) direct immobilisation (without functionalisation of the surface), and b) indirect immobilisation (by funcationalisation of the surface before immobilisation). Functionalisation was introduced with the aim of changing the electrostatic bonds between the surface and origami. It was also intended to see a systematic integration of the origami in the array design.
Immobilisation was performed in the following steps: a) surface cleaning, b) functionalisation, c) immobilisation, d) washing, e) drying. Functionalisation was performed by using a few polymers for site-directed immobilisation of the DNA origami. Once ready, the chips were characterised with Atomic Force Microscopy (AFM). In the AFM we saw variable attachment affinities of DNA origami to the silicon-oxide surface, which needs to be studied further.
We look forward to welcoming partners to further workshops in the future!
All images courtesy of Keshia Sambo