Team:Exeter/Applications

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Polysaccharides have a spectacular range of properties which stem from the relationships between the chemical nature of the sugars, their arrangement within the polymer and the arrangement of the polymer itself. They appear in every corner of the natural world and have multiple applications in nature ranging from protection to energy storage.

Not surprisingly humanity has taken advantage of their diversity and by doing so created a huge variety of uses within the medicinal, material and consumable sectors.

We invite you to take a brief look at what we believe could one day be possible if a system to design bespoke polysaccharides existed.

“It is not what we believe to be impossible that holds us back, but merely the limit to our imagination.”


	The potential for new applications or improvements to current treatments across the medical world is vast. Several polysaccharides currently show biocompatible and biodegradable properties, making them suitable for both external and internal functions. Chitin and chitosan have already been studied for their effect on blood coagulation, tissue growth and wound healing. They are now used in wound dressings to aid the natural healing process and chitin, because of its strength and flexibility and the fact it decomposes completely over time is used as surgical thread for stitches. We would suggest an improvement to dressing wounds would be to make an equivalent in the form of a gel, this could then be coated over an open/closed wound. A gel would offer the advantage of being able to use an open-window type dressing thus enabling the injury to be clearly visible and the healing process closely observed. Not only could a gel be used over a wound, it could also be used during extensive surgeries internally on tissue. This could potentially massively increase the rate of healing. Scientists believe we are overdue a flu-outbreak that would be classed as a pandemic. We believe our research could lead to rapid vaccine production which would save millions in the event of such an outbreak. Collaborations with emerging technologies that stimulate higher B cell activation, polysaccharide vaccines are becoming the way forward as on their own they do not produce an immune response due to fluid phase consumption but in the prescence of the correct antigen would stimulate a strong B cell response. Hyaluronan is a polysaccharide that is present within joints and as a solution offers an interesting property. It is viscoelastic, at low strain frequencies it has viscous behaviour whilst at high strain frequencies it displays elastic tendencies. These properties are what enable joints to survive on a daily basis with normal use and sudden impacts. We think that future prosthetics would benefit from research within this area and could possibly provide a replacement limb capable of rivalling, mechanically, the natural design. They may even progress to be able to withstand larger amounts of impact force making the possibilities of running faster for longer and jumping higher a possibility. Cyclodextrin, as a cyclic oligosaccharide with hydroxyl groups able to hold hydrophobic molecules within them until surrounding become more hydrophobic. This gives them useful applications as drug delivery systems into fatty tissues or organs such as the liver and even bone. Blood types are distinguished by the presence of their surface polysaccharides. Depending on which antigens are present some blood groups can only receive donations from their own group or other specific blood types according to their rarity. This drastically reduces the list of potential options. In the future we envisage a system where donor blood could be “masked” to display the properties of its intended acceptors blood. This would be achieved by creating a polysaccharide that could bind to the surface of donor blood with one end and via the other display the same properties required for the recipient, thus passing as the host blood type. We believe this would lead to a new Universal Blood Donor Group with the potential of replacing conventional methods. And why stop at red blood cells? Could this method of “masking” cells be progressed to donor tissues and organs with the possibility of advancing to the transplant of entire body parts?


	Currently polysaccharides can be found in the process of wastewater treatment. Chitin has been shown to decontaminate plutonium and mercury present in wastewater and chitosan to be able to remove arsenic from contaminated drinking water and petroleum from wastewater. There is also the potential for polysaccharides to be used in the removal of other heavy metals from wastewater. Imagine if you were able to use polysaccharides to at first detect harmful elements within water, obtain a fast signal to say exactly what was present and then also be able to extract all of the contaminant using a polysaccharide removal system! In plants, polysaccharides such as starch are used to store the energy gathered via photosynthesis. If we could manufacture polysaccharides with given electrical properties could it be possible to harness some form of energy and make a fuel cell? And if it were possible could we take it one step further and create mini biological circuits with custom built polysaccharides playing the roles of diodes, resistors and capacitors? And perhaps being successful here would lead to a revolution on the nano-scale, replacing the idea of creating mechanical nanobots and instead attempt a biological one? Last year Suzanne Lee set a challenge; to spin her a bug, align it in a certain direction, grow it around a specific shape and make it hydrophobic. We believe that our project is a step in the right direction to making this a reality. With the ability to create novel polysaccharides and build them with very specific properties, in both physical and electrical, a vast amount of new, unique, and exciting materials could present themselves. One that may be invented could take advantage of xylomannan’s anti-freezing properties found within the Alaskan Beetle able to resist below -70°C. A suit which could withstand such extreme temperatures would have many uses, perhaps predominantly in diving and space suits!


	Polysaccharides are present in most foods but not just as the notorious “e-numbers”. They can be used as edible food glues to accomplish many different types of effects from standard assembly of food parts to highly decorative pieces of food art. Along with its artistic capabilities there are also practical implications in the uses of external polysaccharides when regarding food. They also offer applications in areas such as: thickeners, suspension agents, oxidation resistance, dehydration resistance, and extending the shelf life of the foodstuff. In the future imagine if we could amplify the ability to preserve food... this would have a massive effect on global food shortages. Not only might it be possible to coat, or perhaps even grow, current “perishables” such as fruit and veg but the billion tons worth of food which is wasted each year could find itself ingested instead of buried. With modernised countries overcoming the wasteful nature of today’s attitude, the food which is currently produced to sustain the demand could then be exported to nations who still struggle with producing sufficient quantities of food. When extended space flight becomes a reality, consumable lifetime will be a serious issue. Therefore polysaccharide coating could provide a means to supply a space vessel with not only a sufficient amount of long lasting food but also provisions that are resistant to water loss, bacterial growth, and mutation by ionising radiation. It has been shown that polysaccharides can not only stimulate the germination of some seeds but also protect plants from specific pathogens and funguses. Could further research produce polysaccharides that would improve the rate of growth in more plants? Could crops be grown in weeks rather than months? Could trees be accelerated too?


	Could it be possible to produce polysaccharides that have specific hydro(phobic/phillic) domains that would self-assemble when introduced to water. We believe this could be possible and if it were, imagine what you could use it for! Could it be used to create a small bridge over water or perhaps a quick release raft? And if you could make it into a raft, why not aim a bit bigger and mould a boat or even a cruise liner! If you’ve never been in a situation where you have required the ability to travel over a stretch of water and perhaps need a more practical use using a rubbery material displaying interesting elastic properties then look no further! The self-healing abilities of certain types of supramolecular elastomers arise due to their intermolecular interactions. We think this could be improved upon using research into polysaccharides, to create a glue, gel or paint like product which could be easily sprayed or coated onto materials which need protecting. These could include covering a vehicle to make it effectively “scratch proof” or producing a thinner film to cover screens, like those found on smart phones, which come under a constant barrage of attacks daily from keys and coins! Still not satisfied? We mentioned earlier, in the medical section, the potential of building upon the uses of polysaccharides that have amazing properties when involved with impacts, but could we go further still? Could we create a material that was so finely woven and had so many layers that it could not only stop a bullet but could also distribute the energy involved so the user felt nothing? If a bullet could be stopped by this type of material could a bomb blast be absorbed too? And what about falling with a broken shoot, could a special sky diving suit be made that rendered parachutes obsolete?