DNA nanotechnology allows for the rational construction of synthetic nanoscale structures including nanorobots, motors and devices, via highly specific and programmable base-pairing interactions. We exploit this capacity to design and build a DNA based biosensor for the detection of biomolecules such as miRNA and proteins like antigens.
Achieving this goal requires a detailed understanding of the dynamic properties of single and double stranded DNA in solution as well as DNA hybridization, for which the thermodynamics have been well studied but binding kinetics have not yet been fully elucidated. Here, we use biolayer interferometry (BLItz) for real-time monitoring of DNA hybridization kinetics in combination with computational models to predict the impact of different parameters like strand length or sequence on binding of various DNA constructs. We demonstrate that different DNA sequences with the same GC content can have quite different binding kinetics.
The sensor can in principle be customized for the detection of a range of biomolecules via the chemical attachment of proteins like antibodies using ‘click’ chemistry and hence provide a new platform for the development of point-of-care diagnostics of diseases like HIV or cancer.