Quantum biology is an area of study that investigates the applications of quantum mechanics in biological processes. Though its origins date back to the 1930’s, it is considered a relatively new interdisciplinary field, with the ability of explaining the phenomena of living cells by way of the action of quantum effects. Can technology learn anything from this?
What Is Quantum Biology?
Quantum biology has to do with understanding, specifically, how non-trivial quantum effects have an effect on biological processes of living organisms that they happen within. The non-trivial quantum effects that can have an effect in this way are:
The Quantum Tunneling Effect
In classical mechanics, if we kick a ball against a wall, it would bounce back because the energy of its particles is less than that of the barrier. But in quantum mechanics, electrons have an undulatory (or wave-like) character and can give off a wavefunction capable of going through a potential barrier beyond the energy of its particles. This is what is known as the tunneling effect.
Two quantum states can superimpose one another to generate a third state. The clearest example of this is seen in quantum computing. In contrast to the bit in classical computing, which can only have a value of 1 or 0, a cubit in quantum computing can have both values at the same time.
In physics, coherence is a property of waves that allows for stationary interference. To achieve it, it is necessary that the waves maintain an identical waveform and frequency between them.
Quantum coherence occurs when quantum superposition remains stable; as if these waves interfered one with the other to form a third wave, a third state in this case, that is a superposition of the two previous states. If this stops happening, one would be talking of quantum decoherence, which involves a physical quantum state becoming a classical physical state.
This is also related to quantum superposition, only that in quantum entanglement, the particles share their superposed states to the point that they lose their independence and individualism, forming an inseparable whole (when they do not fall into decoherence). This phenomenon can occur even though the particles might find themselves at a great distance one from the other.
Applications of Quantum Biology
Quantum biology has used the quantum tunneling effect to explain enzymatic catalysis. In this process, the electrons in the interior of the enzymes act as catalysts for generating reactions between organic compounds, but experts were interested in understanding how. In 1989, a University of California, Berkeley study showed that during the catalysis of the oxidation of benzyl alcohol, the transfer of hydrogen occurred by way of the quantum tunneling effect. Currently this theory has general acceptance.
In the study of plants, quantum biology disentangled the understanding of the effectiveness of photosynthesis in the following way: when a photon excites or stimulates an electron of a chlorophyll molecule, it forms an exciton, a quasiparticle that contains both the electron and the electron hole (the lack of an electron where one could be) the aforementioned movement produces. The exciton goes towards the center of photosynthetic reaction with an energy transfer so perfect that can only be explained in quantum terms, because it explores all possible routes in a simultaneous way before electing the most efficient, which requires quantum superposition.
Quantum biology was also applied to the study of magnetoreception, which is to say, the ability of some animals to detect terrestrial magnetic fields (which is fundamental for orientation). It is believed that magnetoreception works through a light-sensitive protein called cryptochrome, which is found in the retinae of birds and other species. The reactions produced in this protein generate free radicals (when electrons circulate alone in one molecule, unpaired within it). But through quantum entanglement, these electrons can align themselves in a distinct way in accordance with the magnetic field. This reaction is transmitted to the brains of the animals.
Another sense that appears to be brought about by quantum phenomena is the sense of smell. The works of Malcolm Dyson (in 1938) and the biophysicist Luca Turin (in 1996) indicate that the receptors of G proteins perceive odors through the distinct vibratory frequencies of the chemical molecules that produce the odors. These molecules come together with receptors, establishing a bridge so that the electrons fully occupy all of the protein via the tunneling effect of the electrons, combining with a quasiparticle that has vibratory properties that is called a phonon.
However, perhaps the most important recent contribution to the field of quantum biology is that which links the tunneling effect of protons with DNA mutations (which involve the disappearance of a proton that later reappears in a place adjacent to the other side of the potential barrier, in this case, a nitrogenized base). This could contribute to understanding diseases that come about because of these mutations, why they themselves are produced, and how to avoid them; it could also help the early detection of cancer.
Mursla is one of the startups interested in this goal. More specifically, they are looking to come to market with products based on quantum biology in the near future, more for the general public than in specialized cases, focusing on diagnostics. Considering that tumors are detected first by the level of certain proteins in the blood, the scientists at Mursla want to implement a technology capable of scanning the proteins in a drop of blood searching for indications of cancer.
This would not be possible without quantum biology, which is changing the way experts see biomolecules, the quantum mechanical behavior that surrounds them, and what we can end up doing with all of this new information.
The theoretical physicist Jim Al-Khalili, one of the researchers of the impact of quantum effects on genetic mutations, thinks that non-trivial quantum effects that affect quantum biology could help lead to the development of new instruments, techniques, or sensors. Some of these new quantum technologies could potentially be applied to synthetic biology, thereby finding in quantum biology a bridge between both fields.
These technologies could also revolutionize renewable energy, as an example, producing new types of photovoltaic cells, Al-Khalili predicts.
Whatever the case may be, quantum biology is in its infancy, and the possibilities — for the moment — are infinite.
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