DNA as Nanowire
The nanowire can be defined as anything whose diameter is measured in nanometres and whose length is at least a thousand times greater than its thickness. The biggest obstacle with the making of a nanowire is making wires of considerable length without them breaking off and that is where DNA comes into the picture.
At the heart of making a nanowire is the ability to allow two different materials for bonding which are also known as hybridized materials or multiple-component materials. DNA strands are of a fixed length and to make them longer, they have to be joined to each other. This is achieved by using proteins. In very rudimentary terms, the DNA acts as the brick while the protein acts as the cement. Protein molecules are attached to both ends of the DNA strands and these protein molecules join hands with protein molecules from another DNA strand. This end to end connection can be repeated as many times as is required to achieve the desirable length of the nanowire. All this is good in theory, but putting it into practice takes a lot of innovation.
Protein has the ability to carry out interactions with other protein molecules like in this case, it can bind to another protein molecule. This is a natural process and is relatively easy to achieve. The difficult part is making a protein molecule bind to a strand of DNA. Researchers at the laboratory of Stephen Mayo have been able to develop a computer program which can generate DNA sequences that can bind to a particular protein molecule. It doesn’t mean the computer does all the heavy lifting. The scientists have to check if each sequence generated is viable in the real world and that it will bind to the said molecule with satisfactory binding strength. In case the first sequence fails, the researcher needs to figure out what additional information is required for the correct sequencing and input that to the computer and start all over again.
All this effort is paying off though, as the successful synthesis of nanowires can solve some of the major problems faced in the fields of electronics and sensing. Computers today are immensely powerful and fast as compared to those from the past. This has been achieved by making the components smaller and smaller. The demand for even faster computers is on the rise and making the semiconductors, that make up a computer, any smaller would mean losing reliability. Which means that these computers will work but the probability of them providing an incorrect result will become too high. A nanowire, on the other hand, can be synthesized in such a way that it possesses the properties of these semiconductors while allowing much greater control and reliability. Nanowires will allow these components to shrink much further thus opening up the doors to huge processing speeds and power.
The field of sensing has already hit a roadblock. Currently, nanowires are made out of silicon and these do not accurately sense the presence of charge in a molecule because the molecule under observation cannot be brought sufficiently close to the silicon nanowire. A DNA nanowire, on the other hand, eliminates this problem and allows the molecule which needs to be tested to come close enough to give an accurate reading which will provide greater insight into the yet undiscovered properties of molecules and atoms allowing mankind to achieve currently impossible feats such as cold fusion.
Almost every innovation in the history of mankind has been achieved by pushing the boundaries of what was thought to be possible. With DNA nanowires our computers will become so powerful that huge amounts of data can be processed in a very short duration of time. They will become small enough to be fitted into almost anything allowing our gadgets and appliances to become smarter. They will also allow advancements in currently dormant fields of science such as space exploration and clean nuclear energy. The DNA sequencing of entire organisms can be mapped faster allowing us to save endangered species. While it is still in its infancy, DNA nanowires could very well be the next biggest innovation of the human race.