The objective of OrigamiSeq is to create an experimental platform that will allow scientists to study how individual biomolecules works. Among the most important techniques that allow us to study isolated biomolecules are single-molecule fluorescence techniques. One of the main challenges that faces the application of single molecule fluorescence techniques in biology is the concentration barrier. This refers to the big difference in concentration required to detect a single molecule and the concentration at which biomolecules work. The density of molecules demanded for biomolecules to work efficiently are usually at least 1000 times higher than that required to achieve single molecule detection. This means that if we use the biomolecules, or their substrate, at their working concentration, we will detect more than one molecule at a time, therefore losing the single molecule information we are seeking to obtain.
To solve this problem we plan to use DNA origami nanoantennas. It is known, due to a combination of physical and chemical-physical phenomena, that a fluorescent molecule placed in the vicinity of a metal can experience an enhancement of its fluorescent emission. On the other hand, the DNA origami technique permits to build nanometer size structures with virtually any kind of shape and functionality. Our group combine both technologies to build nanostructures that can take advantage of this effect to increase the fluorescence signal coming from a single fluorescent molecule. The heart of the so-called DNA origami nanoantenna are two metal nanoparticles brought in proximity, combined with the ability to place selectively molecules in the hotspot where the enhancement is the highest. Since the signal coming from the molecule in the hotspot is far more intense that the signal coming from molecules out of it, metallic nanoantennas allow the detection of a single molecules even when several molecules at present at a time. Using this idea, we will use DNA origami nanotechnology to construct nanoantennas and selectively immobilize a biomolecule in the hotspot to study its behavior at concentrations compatible with their working concentration. We plan to develop a single-molecule DNA sequence technique in order to probe the viability of our idea. The long-term objective is to provide to the scientific community with a general platform with a high versatility that can be used to study a huge variety of biomolecules.
In order to understand how they perform their work, it is of crucial importance to study the molecules that plays key roles in life at the single molecule level. Better understanding of their function will lead us to better understanding of key features of life but also on how their malfunction is related to disease. Therefore paving the way to develop better future treatments for diseases. Besides, the project includes the development of a single-molecule DNA sequencing technology, with potential applications in diagnosis.
