Accurate and timely diagnosis is an important step in the treatment of all diseases. Although traditional approaches to diagnostics have achieved much success in the past, the potential for advanced diagnostics is vastly bigger than what we have managed to unlock so far. The new and expanding frontier in diagnostics is molecular diagnostics, where specific molecules present in a patient's body can be correlated with a particular disease or health condition. In fact, the human body is filled with molecular signatures of disease, right from the beginning of infection or disease initiation. If we could read them, these molecular signatures would tell us much of what we need to know about the health status of an individual, and would inform us how we can intervene to correct disease states. However, these biomolecules are typically only present in very small quantities in the body, and thus they are hard to detect. Further, we might need to detect a large number of different biomolecules to paint a detailed picture of a patient's health status. To unlock the full potential of molecular diagnostics, it is imperative that we develop new technologies that allow sensitive detection of a range of biomolecules in patient samples.
Nanotechnology concerns the synthesis and application of materials in the size regime below 100 nanometers. A human hair is around 50 micrometers wide, which is 50’000 nanometers. Therefore, to reach the nanomaterial size threshold of 100 nanometers, we would need to split a hair 500 times width ways. Scientifically, there are various driving forces behind interest in nanomaterials, including the fact that many materials exhibit unique phenomena – such as intense fluorescence or magnetism – that are not present in bulk, when they are reduced in size into the nanoscale. Further, in the context of biological sciences, nanomaterials are in the same size regime as many biomolecules (e.g. proteins, nucleic acids), therefore they can be readily engineered to interact with biological systems. DNA nanotechnology concerns the use of DNA molecules as structural and functional units in nanomaterial constructs.
There is much potential for innovation in diagnostics by combining functional nanoparticles and enzymes. In scientific research, it has been observed that when the target (substrate) of enzymes are immobilized on nanoparticles, the reactions proceed differently than if the substrates are free in solution. The overall aim of the current project was to study the interaction of DNA nanomaterials with enzymes, working towards uncovering unique phenomena that could be harnessed in the detection of various molecular targets. The work was split into a fundamental side which looked at characterizing DNA nanomaterial–enzyme interactions, and an applied side that looked to create novel sensors and bioassays based on these interactions.
